Horizontal Water Source Heat Pump Units

Horizontal Water Source Heat Pump Units

ContentsModel Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . 2Transportation & Storage . . . . . . . . . . . . . . . . . . . . . . . 2Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Cleaning & Flushing System . . . . . . . . . . . . . . . . . . . . 7Start-up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Operating Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Typical Wiring Diagrams . . . . . . . . . . . . . . . . . . . . 10-13Unit Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Thermostat/Subbase Connections . . . . . . . . . . . . . . . 17Options for Mark IV/AC Units. . . . . . . . . . . . . . . . . . . 19Field Installed Options on MicroTech Units . . . . . . . . 23Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Installation & Maintenance Data

Group: WSHP

Part Number: # 106018861

Date: December 1999

IM 526-11

©1999 AAF-McQuay Incorporated IM 526-11 (Rev. 12/99)

Page 2 / IM 526

Transportation & Storage

InstallationGeneral

Upon receipt of the equipment, check carton for visibledamage. Make a notation on the shipper’s delivery ticketbefore signing. If there is any evidence of rough handling,immediately open the cartons to check for concealed dam-age. If any damage is found, notify the carrier within 48hours to establish your claim and request their inspectionand a report. The Warranty Claims Department should thenbe contacted.

Do not stand or transport the machines on end. For stor-ing, each carton is marked with “up” arrows.

In the event that elevator transfer makes up-ended posi-tioning unavoidable, absolutely ensure that the machine isin the normal upright position for at least 24 hours beforeoperating.

Temporary storage at the job site must be indoors, com-pletely sheltered from rain, snow, etc. High or low tempera-tures naturally associated with weather patterns will notharm the conditioners. Excessively high temperatures,140°F (60°C) and higher, may deteriorate certain plasticmaterials and cause permanent damage.

1. To prevent damage, this equipment should not beoperated for supplementary heating and cooling duringthe construction period.

2. Inspect the carton for any specific tagging numbersindicated by the factory per a request from theinstalling contractor. At this time the voltage, phaseand capacity should be checked against the plans.

3. Check the unit size against the plans to ensure unitinstallation is in the correct location.

4. After removing the carton, remove the hanger kit fromthe fan housing.

5. Before installation, check the available ceiling heightversus the height of the unit.

6. Note the location and routing of water piping, conden-sate drain piping, and electrical wiring. The locations ofthese items are clearly marked on submittal drawings.

7. The installing contractor will find it beneficial to confer

with piping, sheet metal, ceiling and electrical foremenbefore installing any conditioners.

8. Remove all shipping blocks in the fan wheel.

9. Change the airflow direction from straight discharge toend discharge or vice versa before the unit is installedin the ceiling. Refer to the section in this bulletin forinstructions.

10. We recommend that the contractor cover the condi-tioners with plastic film to protect the machines duringfinishing of the building. This is critical while sprayingfireproofing material on bar joists, sandblasting, spraypainting and plastering. If plastic film is not available,the shipping carton may be modified to cover the unitsduring construction.

11. On units with spring mounted compressors, removethe hold-down bolt from the bottom of the unit beforestarting compressor.

Model Nomenclature

Product CatagoryW = WSHP

Product IdentifierSee box below

Design Series1 = A Design 4 = D Design2 = B Design 5 = E Design3 = C Design

Nominal Capacity007 = 7,000 015 = 15,000009 = 9,000 019 = 19,000012 = 12,000 etc....

Note: Installation and maintenance are to be performed only by qualified personnel who are familiar with local codesand regulations, and are experienced with this type of equipment. Caution: Sharp edges are a potential injury hazard.Avoid contact with them.

W CDD 1 009 D Z

Coil OptionsNone

VoltageE = 208/230-60-1F = 208/23-60-3J = 265-60-1K = 460-60-3L = 575-60-3M = 230-50-1N = 380-50-3

McQuay Product Identifiers

CDD = Ceiling mtd./DDC Controls/Ext. Range/Less Board CME = Ceiling mtd./Mark IV/Ext. RangeCDE = Ceiling mtd./DDC Controls/Ext. Range CMG = Ceiling mtd./Mark IV/GeothermalCDL = Ceiling mtd./DDC Controls/Std. Range/Less Board CMS = Ceiling mtd./Mark IV/Std. RangeCDS = Ceiling mtd./DDC Controls/Std. Range CMU = Ceiling mtd./Mark IV/European Spec.

Figure 1B. Hanger bracket detail, sizes 070 thru 120

44"(1118mm)

42"(1067mm)

80" (2032 mm)

82" (2083 mm)

Airflow

Comp

Comp

ControlBox

2"(51 mm)

2"(51 mm)

FanAssembly

Coil

UNIT DIMENSIONS (INCHES)SIZE A B C D E F G H

007 – 012 38 36 321⁄2 201⁄4 22 181⁄2 34 20015 – 030 44 42 381⁄2 201⁄4 22 181⁄2 40 20035 – 042 50 48 441⁄2 201⁄4 22 181⁄2 46 20048 & 060 545⁄16 525⁄16 48 285⁄32 30 26 50 28070 – 120 See Figure 1B

IM 526 / Page 3

Unit Location1. Locate the unit in an area that allows for easy removal of

the filter and access panels. Leave enough space forservice personnel to perform maintenance or repair.Provide sufficient room to make water, electrical andduct connections.

2. The contractor should make sure that adequate ceilingpanel access exists, including clearance for hangerbrackets, duct collars and fittings at water and electricalconnections.

3. Allow adequate room below the unit for a condensatetrap and do not locate the unit above pipes.

4. Each unit is suspended from the ceiling by four threadedrods. The rods are attached to the unit corners by a hang-er bracket through a rubber isolator. Caution: Do not userods smaller than specified below. The rods must besecurely anchored to the ceiling or to the bar joists.

Figure 1A. Hanger bracket detail, sizes 007 thru 060

Figure 1C. Unit sizes 007 thru 060

Figure 1E. Unit sizes 070 thru 120

5. Each unit is furnished with a hanger kit. The kit isshipped unassembled and includes hanger brackets,rubber isolators, washers, bolts and lock washers. Layout the threaded rods per the dimensions in Figures 1Aand 1B. Assemble the hangers to the unit as shown inFigures 1C, 1D and 1E. Securely tighten the brackets tothe unit.

6. When attaching the hanger rods to the unit, a double nutis recommended since vibration could loosen a singlenut. The installer is responsible for providing the hex nutswhen installing hanger rods.

7. Leave minimum 3" (76 mm) extra threaded rod below thedouble nuts or minimum 3" (76 mm) clearance betweentop of unit and ceiling above to facilitate top panelremoval for servicing

8. The unit should be pitched towards the drain in bothdirections to facilitate condensate removal.

UNIT DIMENSIONS (mm)SIZE A B C D E F G H

007 – 012 965 914 826 514 559 470 864 508015 – 030 1118 1067 978 514 559 470 1016 508035 – 042 1270 1219 1130 514 559 470 1168 508048 & 060 1380 1329 1219 715 762 660 1270 711070 – 120 See Figure 1B

Hanger bracket dimensions

3⁄8" Threaded Rod(By Others)

Vibration Isolator

Washer

Hex Nuts(By Others)

Bolt & LockWasher

By McQuayInternational

By Others

By Others

A

B

CoilAirflow

1-15/16"(51 mm)

H D E

CG

1-7/8"(48 mm)

Comp

ControlBox

FanAssembly

D

DeflectionForce

h

D

d

Span Length (t)

C

Page 4 / IM 526

h =t

64

amount to provide a grip for removing.)

2. Adjust sheave pitch diameter for desired speed by open-ing moving parts by half or full turns from closed posi-tion. Do not open more than five full turns.

3. Replace external key “E” and securely tighten setscrews“B” over key and setscrews “C” into keyway in fixed halfof the sheave.

4. Put on belts and adjust belt tension to 4 lbs. –0.7 lbs.(18N –3N) for a 1⁄2" to 3⁄4" (13 mm to 19 mm) belt deflec-tion height.

5. To determine the deflection distance from normal posi-tion, use a straightedge or stretch a cord from sheave tosheave to use as a reference line. On multiple-belt drivesan adjacent undeflected belt can be used as a reference.

6. Future adjustments should be made by loosening thebelt tension and increasing or decreasing the pitch diam-eter of the sheave by half or full turns as required.Readjust belt tension before starting drive.

7. Be sure that all keys are in place and that all setscrewsare tight before starting drive. Check setscrews and belttension after 24 hours service.

8. When new V-belts are installed on a drive, the initial ten-sion will drop rapidly during the first few hours. Checktension frequently during the first 24 hours of operation.Subsequent retensioning should fall between the mini-mum and maximum force.

Unit Motor RPM Factory Motor SheaveSize HP Range Setting (RPM) Position

11⁄2 756 – 902 785 4 Turns Open070 3 907 –1081 904 5 Turns Open

11⁄2 698 – 832 858 11⁄2 Turns Open090 3 907 –1081 904 5 Turns Open

3 756 – 901 814 3 Turns Open120 5 907 –1081 904 5 Turns Open

Air BalancingUnit sizes 070 thru 120 are supplied with a variable pitchmotor sheave to aid in airflow adjustment. They are set atthe factory according to Chart 1 shown below.

When the final adjustments are complete, the currentdraw of the motors should be checked and compared tothe full load current rating of the motors. The amperagemust not exceed the service factor stamped on the motornameplate.

Upon completion of the air balance, it is a commonindustry recommendation that the variable pitched motorsheave be replaced with a properly sized fixed sheave. Amatching fixed sheave will provide longer belt and bearinglife and vibration free operation. Initially, it is best to have avariable pitched motor sheave for the purpose of air bal-ancing, but once the balance has been achieved, fixedsheaves maintain balancing and alignment more effectively.

Adjustment (See Figure 2)1. All sheaves should be mounted on the motor or driving

shaft with the setscrew “A” toward the motor

2. Be sure both driving and driven sheaves are in alignmentand that shafts are parallel.

3. Fit internal key “D” between sheave and shaft, and locksetscrew “A” securely in place.

Adjusting1. Loosen setscrews “B” and “C” in moving parts of sheave

and pull out external key “E”. (This key projects a small

B

E

A

D

C

Single Groove

Key E projects toprovide a grip forremoving.

Figure 3. Drive belt adjustmentFigure 2.

Chart 1A. 60 Hz

( )

Where: t = Span length, inches (mm)C = Center distance, inches (mm)D = Larger sheave diameter, inches (mm)d = Smaller sheave diameter, inches (m)h = Deflection height, inches (mm)

Note: The ratio of deflection to belt span is 1:64.

Chart 1B. 50 Hz

Filter Access

t = C2 –D-d

2

Unit Motor RPM Factory Motor SheaveSize HP Range Setting (RPM) Position070 11⁄2 756 – 901 786 4 Turns Open090 11⁄2 720 – 860 858 11⁄2 Turns Open120 3 756 – 902 815 3 Turns Open

Each unit is shipped with a filter bracket for side filterremoval. For bottom removal push the filter up into topbracket to gain clearance of bottom bracket and removethe filter.

IM 526 / Page 5

Air Discharge ConversionUnit sizes 007 thru 060 can be shipped as straight dis-charge air or end discharge air arrangement. Most likely, theunit will have to be converted from straight discharge to enddischarge. To accomplish this:

1. Remove top panel.

2. Remove the access panel to the fan motor. Remove thepiece of insulation at the bottom on the side of the bot-tom panel.

3. Remove the fan discharge panel, rotate it 180 degrees,and move it to the other side. In other words, with

straight air discharge the housing is bottom horizontaland with an end discharge the housing is top horizontal.

4. Remove the three bolts holding the fan motor on androtate it so that the motor oilers are in the up position.

5. Install insulation base panel below new access panellocation.

6. Reinstall the top panel.

7. Reinstall the piece of insulation and the access panel.

Ductwork & AttenuationDischarge ductwork is normally used with these condition-ers. Return air ductwork may also be required.

All ductwork should conform to industry standards ofgood practice as described in the ASHRAE Systems Guide.

The discharge duct system will normally consist of aflexible connector at the unit, a transition piece to the fullduct size, a short run of duct, an elbow without vanes, anda trunk duct teeing into a branch duct with discharge dif-fusers as shown in Figure 4. The transition piece must nothave angles totaling more than 30° or severe loss of air per-formance can result. Do not connect the full duct size to theunit without using a transition piece down to the size of thedischarge collar on the unit. With metal duct material, thesides only of the elbow and entire branch duct should beinternally lined with acoustic fibrous insulation for soundattenuation. Glass fiber duct board material is more absorb-ing and may permit omission of the canvas connector.

The ductwork should be laid out so that there is no lineof sight between the conditioner discharge and the distrib-

ution diffusers.Return air ducts can be brought in through a low side

wall filter-grille and then up through the stud pieces to aceiling plenum or through air ceiling filter-grilles. The ceilingfilter-grille must not be placed directly under the condition-er.

Return air ductwork can be connected to the standardfilter rack. See Figure 5 (side filter removal shown). The fil-ter rack can be installed for bottom filter removal or side fil-ter removal by locating the brackets. For side filter removalthe brackets should be located on the bottom, left side, andtop. For bottom filter removal the brackets should bemounted on the left side top and right side with the springclips supporting the filter.

Do not use sheet metal screws directly into the unit cab-inet for connection of supply or return air ductwork, espe-cially return air ductwork which can hit the drain pan or theair coil.

Figure 4. Figure 5. Filter rack/return air duct collar

2x2 Ft.Diffuser(ExampleOnly)

Branch DuctInternally LinedWith AcousticFibrousInsulation

Trunk Duct

Square Elbow

CanvasCollar

HeatPump

TransformationPiece

Discharge CollarOn Heat Pump

Both Sides Internally Lined WithAcoustic Fibrous Glass Insulation

Suggested Duct Layout ForMultiple Diffuser Application

Standard 1" (25mm) and2" (51 mm) for sizes007 thru 060

Standard 2" (51 mm)for sizes 070 thru 120

Ventilation may require outside air. The temperature of theventilation air must be controlled so that mixture of outsideair and return air entering the conditioner does not exceedconditioner application limits. It is also typical to close offthe ventilation air system during unoccupied periods (nightsetback).

The ventilation air system is generally a separate build-

Ventilation Airing subsystem with distribution ductwork. Simple introduc-tion of the outside air into each return air plenum chamberreasonably close to the conditioner air inlet is not only ade-quate, but recommended. Do not duct outside air directly tothe conditioner inlet. Provide sufficient distance for thor-ough mixing of outside and return air. See Operating Limitson page 10.

Page 6 / IM 526

Electrical Data

1. Verify the compatibility between the voltage and phaseof the available power and that shown on the unit serialplate. Line and low voltage wiring must comply with localcodes or the National Electrical Code, whicheverapplies.

2. Apply correct line voltage to the unit. A 7⁄8" (22mm) holeand/or a 11⁄8" (29 mm) knockout is supplied on the sideof the unit. A disconnect switch near the unit is requiredby code. Power to the unit must be sized correctly andhave dual element (Class RK5) fuses or an HACR circuit

Generalbreaker for branch circuit overcurrent protection. See thenameplate for correct ratings.

3. Three phase 50 cycle units, 380/50/3, require a neutralwire for 230/50/1 power to the fan circuit.

4. Connect the thermostat/subbase wiring with the power“off ” to the unit.

5. Field supplied relays installed on the input terminalsW1, W2, Y1, Y2 or G may introduce electrical noise.Never install relay coils in series with the inputs.

230 Volt Operation

Fan Speed Change

All 208-230 volt single-phase and three-phase units are fac-tory wired for 208 volt operation. For 230 phase operation,the line voltage tap on the 24 volt transformer must be

Unit sizes 006 through 060 have three-speed fan motorsand are shipped for maximum performance and minimumsound requirements.Unit sizes 006 through 009 are wired on low speed, size 012is wired on high speed (Figure 6). On unit sizes 015 through

changed. Disconnect and cap the red lead wire and inter-change it with the orange lead wire on the primary of the 24volt transformer.

Figure 6. Sizes 006 through 012

Piping1. All units should be connected to supply and return pip-

ing in a two-pipe reverse return configuration. Areverse return system is inherently self-balancing andrequires only trim balancing where multiple quantitiesof units with different flow and pressure drop charac-teristics exist in the same loop. Check for proper waterbalance by measuring differential temperature readingacross the water connections. To insure proper waterflow, the differential flow should be 10°F to 14°F (5°C to8°C) for units in cooling mode.

A direct return system may also work acceptably,but proper water flow balancing is more difficult toachieve and maintain.

2. The piping can be steel, copper or PVC.

3. Supply and return runouts usually join the unit via shortlengths of high pressure flexible hose which are soundattenuators for both unit operating noise and hydraulicpumping noise. One end of the hose should have aswivel fitting to facilitate removal for service. Hard pip-ing can also be brought directly to the unit. This optionis not recommended since no vibration or noise atten-uation can be accomplished. The hard piping musthave unions to facilitate unit removal. See Figure 7 fortypical piping setup.

4. Some flexible hose threaded fittings are supplied withsealant compound. If not, apply Teflon tape to assure atight seal.

5. Supply and return shutoff valves are required at eachconditioner. The return valve is used for balancing andshould have a “memory stop” so that it can always beclosed off but can only be reopened to the proper posi-tion for the flow required.

6. No unit should be connected to the supply and returnpiping until the water system has been cleaned andflushed completely. After the cleaning and flushing hastaken place, the initial connection should have allvalves wide open in preparation for water system flush-ing.

7. Units with water regulating valves need to have thecapillary routed outside the unit through a notch in theaccess panel. Be sure to install the split rubber grom-met (supplied) in this notch to protect the capillary andcheck to ensure that all other parts of the capillary donot contact other steel or copper parts. Install the valvein the return water line.

8. Condensate piping can be steel, copper or PVC. Eachunit includes a condensate connection.

060, each fan motor is supplied with a 5-pin terminal blockmounted on the fan motor. Unit sizes 015, 019, 024, 036 arewired on low speed; unit sizes 030 and 048 are wired onmedium speed; and unit sizes 042 and 060 are wired onhigh speed (Figure 6a).

Figure 6a. Sizes 015 through 060

FANMOTOR

FANMOTOR

WHITE (COMMON)

BROWN (CAPACITOR)

BLUE (HIGH SPEED) SIZE 012

RED (LOW SPEED)SIZES 006-009, 015, 024

WHITE (COMMON)

BROWN (CAPACITOR)

BLACK (HIGH SPEED) SIZES 042, 060

BLUE (MED. SPEED) SIZES 030, 048

RED (LOW SPEED)SIZES -015, 019, 024, 036

IM 526 / Page 7

9. The condensate disposal piping must have a trap. Thepiping must be pitched away from the unit not less than1⁄4" per foot (21 mm per meter) (see Figure 8). Generally,the condensate trap is made of copper and solderedon the unit. A piece of vinyl hose from the trap to thedrain line is used for simple removal. A complete cop-per or PVC condensate system can also be used.Union fittings in the copper lines should be applied tofacilitate removal. Factory supplied condensate hoseassemblies have pipe thread fittings to facilitate con-nection of a flexible vinyl or steel braided hose.

Figure 7. (Sizes 007 through 060 shown) Figure 8.

BallValves

SupplyRiser

ReturnRiser

CondensateRiser

Supply Air

OptionalCleanout

11⁄2"(38 mm)

11⁄2"(38 mm)

Hanger Kits (4)

Flex Hoses

Electrical Access Panel

1⁄4" Per Foot(21 mm PerMeter)

10. Do not locate any point in the drain system above thedrain connection of any unit.

11. Automatic flow controlled devices must not be installedprior to system cleaning and flushing.

12. A high point of the piping system must be vented.

13. Check local code for the need for dielectric fittings.

Cleaning & Flushing System1. Prior to first operation of any conditioner, the water cir-

culating system must be cleaned and flushed of all con-struction dirt and debris.

If the conditioners are equipped with water shutoffvalves, either electric or pressure operated, the supplyand return runouts must be connected together at eachconditioner location. This will prevent the introduction ofdirt into the unit. See Figure 9.

Figure 9.

2. Fill the system at the city water makeup connection withall air vents open. After filling, close all air vents.

The contractor should start main circulator with thepressure reducing valve open. Check vents in sequenceto bleed off any trapped air, ensuring circulation throughall components of the system.

Power to the heat rejector unit should be off, and thesupplementary heat control set at 80°F (27°C).

While circulating water, the contractor should checkand repair any leaks in the piping. Drains at the lowestpoint(s) in the system should be opened for initial flushand blowdown, making sure city water fill valves are setto make up water at the same rate. Check the pressuregauge at pump suction and manually adjust the makeupto hold the same positive steady pressure both beforeand after opening the drain valves. Flush should contin-ue for at least two hours, or longer if required, to seeclear, clean drain water.

3. Shut off supplemental heater and circulator pump andopen all drains and vents to completely drain down thesystem. Short circuited supply and return runouts shouldnow be connected to the conditioner supply and returnconnections. Do not use sealers at the swivel flare con-nections of hoses.

4. Trisodium phosphate was formerly recommended as acleaning agent during flushing. However, many statesand localities ban the introduction of phosphates intotheir sewage systems. The current recommendation is tosimply flush longer with warm 80°F (27°C) water.

Return Runout

Supply Runout

Mains

Flexible Hose

Runouts InitiallyConnected Together

Page 8 / IM 526

Start-up1. Open all valves to full open position and turn on power

to the conditioner.

2. Set thermostat for “Fan Only” operation by selecting“Off” at the system switch and “On” at the fan switch.If “Auto” fan operation is selected, the fan will cyclewith the compressor. Check for proper air delivery.

3. For those units that have two-speed motors, reconnectfor low speed operation if necessary.

4. Set thermostat to “Cool.” If the thermostat is an auto-matic changeover type, simply set the cooling temper-ature to the coolest position. On manual changeovertypes additionally select “Cool” at the systemswitch.

Again, many conditioners have time delays whichprotect the compressor(s) against short cycling. After afew minutes of operation, check the discharge grillesfor cool air delivery. Measure the temperature differ-ence between entering and leaving water. It should beapproximately 11⁄2 times greater than the heating modetemperature difference. For example, if the coolingtemperature difference is 15°F (8°C), the heating tem-perature difference should have been 10°F (5°C).Without automatic flow control valves, target a coolingtemperature difference of 10°F to 14°F (5°C to 8°C).Adjust the combination shutoff/balancing valve in thereturn line to a water flow rate which will result in the10˚F to 14°F (5°C to 8°C) difference.

5. Set thermostat to “Heat.” If the thermostat is the auto-matic changeover type, set system switch to the“Auto” position and depress the heat setting to thewarmest selection. Some conditioners have built-intime delays which prevent the compressor from imme-diately starting. With most control schemes, the fan willstart immediately. After a few minutes of compressor

operation, check for warm air delivery at dischargegrille. If this is a “cold building” start-up, leave unit run-ning until return air to the unit is at least 65°F (18°C).

Measure the temperature difference between enter-ing and leaving air and entering and leaving water. Withentering water of 60°F to 80°F (16°C to 27°C), leavingwater should be 6°F to 12°F (3.3°C to 6.6°C) cooler,and the air temperature rise through the machineshould not exceed 35°F (19°C). If the air temperatureexceeds 35°F (19°C), then the water flow rate is inade-quate.

6. Check the elevation and cleanliness of the condensateline. If the air is too dry for sufficient dehumidification,slowly pour enough water into the condensate pan toensure proper drainage.

7. If the conditioner does not operate, check the followingpoints:a. Is supply voltage to the machine compatible?b. Is thermostat type appropriate?c. Is thermostat wiring correct?

8. If the conditioner operates but stops after a brief period:a. Is there proper airflow? Check for dirty filter, incor-

rect fan rotation (3-phase fan motors only), or incor-rect ductwork.

b. Is there proper water flow rate within temperaturelimits? Check water balancing; backflush unit if dirt-clogged.

9. Check for vibrating refrigerant piping, fan wheels, etc.

10. Do not lubricate the fan motor during the first year ofoperation as it is prelubricated at the factory.

11. Field supplied relays installed on the input terminalsW1, W2, Y1, Y2 or G may introduce electrical noise.Never install relay coils in series with the inputs.

5. Refill the system with clean water. Test the water usinglitmus paper for acidity, and treat as required to leave thewater slightly alkaline (pH 7.5 to 8.5). The specified per-centage of antifreeze may also be added at this time.Use commercial grade antifreeze designed for HVACsystems only. Do not use automotive grade antifreeze.

Once the system has been filled with clean water andantifreeze (if used), precautions should be taken to pro-tect the system from dirty water conditions. Dirty waterwill result in system wide degradation of performanceand solids may clog valves, strainers, flow regulators,etc. Additionally, the heat exchanger may becomeclogged which reduces compressor service life or caus-

es premature failure. A SystemSaver® from McQuayInternational should be employed to continuously re-move solids as the system operates. Contact your localrepresentative for further information on this device.

6. Set the loop water controller heat add setpoint to 70°F(21°C) and the heat rejection setpoint to 85°F (29°C).Supply power to all motors and start the circulatingpumps. After full flow has been established through allcomponents including the heat rejector (regardless ofseason) and air vented and loop temperatures stabilized,each of the conditioners will be ready for check, test andstart-up, air balancing, and water balancing.

IM 526 / Page 9

Operating Limits

Extended RangeStandard Units

UnitsCooling Heating Cooling Heating

Min. Ambient Air 50˚F/10˚C 50˚F/10˚C 40˚F/5˚C 40˚F/5˚C Normal Ambient Air 80˚F/27˚C 70˚F/21˚C 80˚F/27˚C 70˚F/21˚CMax. Ambient Air 100˚F/38˚C 85˚F/29˚C 100˚F/38˚C 85˚F/29˚CMin. Ent. Air ➀ ➁ 50˚F/10˚C 50˚F/10˚C 50˚F/10˚C 40˚F/5˚CNormal Ent. Air, 80/67˚F 70˚F 80/67˚F 70˚Fdw/wb 27/19˚C 21˚C 27/19˚C 21˚CMax. Ent. Air 100/83˚F 80˚F 100/83˚F 80˚Cdb/wb ➀ ➁ 38/28˚C 27˚C 38/28˚C 27˚C

➀ At ARI flow rate.➁ Maximum and minimum values may not be combined. If one value is

at maximum or minimum, the other two conditions may not exceedthe normal condition for standard units. Extended range units maycombine any two maximum or minimum conditions, but not morethan two, with all other conditions being normal conditions.

This equipment is designed for indoor installation only.Sheltered locations such as attics, garages, etc., generallywill not provide sufficient protection against extremes in

Environment

Standard unitsUnits are designed to start and operate in an ambient of40°F (5°C), with entering air at 40°F (5°C), with enteringwater at 70°F (21°C), with both air and water flow ratesused in the ARI Standard 320-86 rating test, for initial start-up in winter.

Note: This is not a normal or continuous operating con-dition. It is assumed that such a start-up is for the purposeof bringing the building space up to occupancy tempera-ture.

Extended range unitsExtended range heat pump conditioners are designed tostart and operate in an ambient of 40°F (5°C), with enteringair at 40°F (5°C), with entering water at 40°F (5°C), with bothair and water at flow rates used in the ARI Standard 320-86rating test, for initial start-up in winter.

Power SupplyA voltage variation of 510% of nameplate utilization voltage is acceptable. Three-phase systemunbalance shall not exceed 2%.

temperature and/or humidity, and equipment performance,reliability, and service life may be adversely affected.

Air and water limits Water enthalpyExtended Range

Standard UnitsUnits

Cooling Heating Cooling HeatingMin. Ent. Water ➀ ➁ 55°F/13°C 55°F/13°C 40°F/5°C 40°F/5°CNormal Ent. Water 85°F/29˚C 70˚F/21°C 85°F/29˚C 70˚F/21°CMax. Ent. Air ➀ ➁ 110°F/43˚C 90°F/32°C 110°F/43˚C 90°F/32°C

Additional Information For Initial Start-up OnlyNote: This is not a normal or continuous operating con-

dition. It is assumed that such a start-up is for the purposeof bringing the building space up to occupancy tempera-ture.

Operating voltages115/60/1 . . . . . . . . . . . . . . . 104 volts min.; 127 volts max.208-230/60/1 . . . . . . . . . . . 197 volts min.; 253 volts max.265/60/1 . . . . . . . . . . . . . . . 238 volts min.; 292 volts max.230/50/1 . . . . . . . . . . . . . . . 197 volts min.; 253 volts max.460/60/3 . . . . . . . . . . . . . . . 414 volts min.; 506 volts max.380/50/3 . . . . . . . . . . . . . . . 342 volts min.; 418 volts max.575/60/3 . . . . . . . . . . . . . . . 515 volts min.; 632 volts max.

Note: Voltages listed are to show voltage range. However,units operating with overvoltage and undervoltage forextended periods of time will experience premature com-ponent failure.

Page 10 / IM 526

Typical Wiring Diagrams

Notes:

1. Unit is factory wired for 208V operation. If 230V power supply is used,transformer must be rewired by disconnecting the power lead from thered transformer primary wire and connecting the power lead to theorange transformer primary wire. Place an insulation cap on the redtransformer primary wire.

2. All temperature and pressure switches are normally closed.

3. Component layout shown below is typical. Some components may notbe used on this model or voltage.

4. Mark IV/AC controller board contains a static sensitive microprocessor.Proper grounding of field service personnel should be observed or dam-age to controller may result.

5. Terminal block on Mark IV/AC board provides 24 VAC at terminals R andC. All other outputs are 24 VDC.

6. Field supplied relays installed on the input terminals (W1, W2, Y1 orG) may interfere with proper unit operation. Never install relay coilsin series with inputs.

7. For more information pertaining to the Mark IV/AC controller, refer toOM120.

Figure 10. Typical Mark IV/AC single circuit wiring diagram

COMPONENT LAYOUT➀ COMPRESSOR CONTACTOR➁ FAN CONTACTOR➂ TRANSFORMER➃ PC BOARD➄ AUXILIARY RELAY➅ CIRCUIT BREAKER

CC COMPRESSOR CONTACTORHTR CRANKCASE HEATERCAP MOTOR CAPACITOR

(optional)

IM 526 / Page 11

Notes:

1. On 208/230V units, unit is factory wired for 208V operation. If 230Vpower supply is used, transformer must be rewired by disconnecting thepower lead from the red transformer primary wire and connecting thepower lead to the orange transformer primary wire. Place an insulationcap on the red transformer primary wire.


Figure 11. Typical Mark IV/AC dual circuit wiring diagram

COMPONENT LAYOUT➀ COMPRESSOR

CONTACTOR➁ FAN CONTACTOR➂ TRANSFORMER➃ TRANSFORMER➄ PC BOARD➅ CIRCUIT BREAKER➆ OVERLOAD➇ GROUND LUG➈ POWER BLOCK

(optional) (optional)

Compr

T1

RDRD

75460 & 575V

Only

10

18

BK23RD 208V

BK/RD 460VBK 575V

OR 240V

52

YE

51Lo Press

Lo Temp

Hi PressRV

Solenoid

2938

23Fan Relay

BR

BR

3031

2932

3334

36

37

MicroTechController

3528

27

26

2524

J4 14 1213 11 910 8 67 5 34 12 1011

69 E

L

U

P

C73

73

J212

12121212121212

62

63

64

65

Terminal Board #11st Option

(Factory InstalledSee Note 3)

66

67

6874

75

76

5

43

2

1

1110987654321J1

Dis

char

ge A

ir In

Dis

char

ge A

ir C

om

Wat

er O

ut In

Wat

er O

ut C

om

Aux

Mod

ule

DC

+

Aux

Mod

ule

DC

Com

Aux

Mod

ule

SE

L 1

Aux

Mod

ule

SE

L 2

Aux

Mod

ule

CLK

Aux

Mod

ule

XM

T

Aux

Mod

ule

RC

V

Lo T

emp

SR

C

Con

den

sate

Lo P

ress

SIG

Lo T

emp

SIG

Lo P

ress

SR

C

RV

Com

Hi P

ress

SIG

Com

p C

om

RV

Out

Fan

Com

Com

p O

ut

Fan

Out

Rem

ote

DI S

RC

Rem

ote

DI S

IG

Sp

are

Rel

ay N

C

Sp

are

Rel

ay C

om

Sp

are

Rel

ay N

O

RM

Sen

sor

LED

Tena

nt O

verr

ide

RM

Sen

sor

In

RM

Sen

sor

Com

Lon

Talk

Lon

Talk

24VA

C C

om

24V

Gnd

24VA

C

70

71 (See Note 3)

72 (See Note 3)

J5 89 67 45 3 1 J62

37

36

22

23

35

Fan Relay460 & 575V Only

FanMotor

575V Only

34

1 2 3 4 5

22

1920

21

Cap

A B7

5

1 2 3

CondensateOverflow

24VAC

Line

BK

32

ComprContr

DischargeAir

19

20

RDYE

21

YE

WH

RD

GN

BL

OR

BK

56

5554

53

WaterOut

BR

FanMotor

Cap

22

BK

213

4

52

51

J2

J1

1

2

1

2

3

4

5

6

7

Aux

iliar

y M

odul

e(O

ptio

nal)

BL

321

L3L2L1

T2

T3

Term

inal

Boa

rd #

2

RedTapeEnd

CircutBreaker

(optional)

Page 12 / IM 526

Figure 12. Typical MicroTech 2000 WSHP unit controller single circuit wiring diagram

Notes:

1. Unit is factory wired for 208V operation. If 230V power supply is used,transformer must be rewired by disconnecting the power lead from thered transformer primary wire and connecting the power lead to theorange transformer primary wire. Place an insulation cap on the redtransformer primary wire.


3. Wires 71 and 72 used only on units with no factory installed options.

IM 526 / Page 13

Gnd LugL1

1261

M1

252

2

3

PB1

1 2 3

T1

L2

T2

L3

T3

L1T122

23

27

Heater(Ext. Rng. Only)

Heater(Ext. Rng. Only)

Compr.Mtr.

128

(50Hz Only)

19

M2

T1

T2

T3

L1

L2

L31213

M3

T1

T2

T3

L1

L2

L31415

10 11

BK

YE

45BL

44

24V

60

C

C

BR

BR

8485

12341234432143

4445

1J2 J1

J11 J10

AuxiliaryModule

MicroTechController

J8 J4

2 1 2 3 4 5 6 7

55 535456

Dis

chA

irW

ater

Out

YEWH

RDGN

43

42

41

40

3938

BR

BR

59 C

C

M2

M1RV1

C

C C3 & 5 HP Only

96

C

37

3

2 HP

1

LP1

LT1

36

35

34

33

Con

den

sate

Lo T

emp

SR

CLo

Tem

p S

IGLo

PR

ess

SIG

Lo P

ress

SR

CH

i Pre

ss S

IGR

V C

omR

V O

utC

omp

Com

Com

p O

utFa

n C

om

Fan

Out

24VA

C24

V G

nd

Rem

ote

DI S

RC

Rem

ote

DI S

IGS

par

e R

elay

NC

Sp

are

Rel

ay N

OS

par

e R

elay

Com

RM

Sen

sor

LED

Tena

nt O

verr

ide

RM

Sen

sor

InR

M S

enso

r C

omLo

n Ta

lkLo

n Ta

lk24

VAC

Com

Aux

Mod

ule

DC

Com

Aux

Mod

ule

DC

+A

ux M

odul

e S

EL

2A

ux M

odul

e S

EL

1

Aux

Mod

ule

CLK

Aux

Mod

ule

RC

VA

ux M

odul

e X

MT

Dis

char

ge A

ir C

om

Dis

char

ge A

ir In

Wat

er O

ut C

omW

ater

Out

In

Term

inal

Boa

rd #

2

34

32

CondensateOverflow

30

1413121110 9 8 7 6 5 4 3 2 1 1110 9 8 7

ELUPC

6 5 4 3

69

J1 J21

6263

6465

6667

6874

Terminal Board #11st Option

(Factory InstalledSee Note 1)

75

761 2 3 4 5 6 7 8 9

2 3 4 5 6 7 8 9 101112

7071 (See Note 1)72 (See Note 1)

73

73

2 1

31

32 BLOR

BK

J6J5J4

21

7778

3

3

M3

81

RV2

8382

8079

LP2

LT2 H

P2

81

T1 (75VA)

BK/RD 460VOR 230VRD 208VBK 575VVT 400V

19

20

T1

29(50Hz only)

Compr.Mtr.

2

T2

21T3

T1T2T3

20

21

7

8129

13

4

5 14

6 16

FanMtr.

24 (3 & 5 HP)3 (1.5 HP

L2T2

Ext. Overloads3 & 5 HP only

3 4

52

1

Red Tape End

CircutBreaker

(optional)

Figure 13. Typical MicroTech WSHP unit controller dual circuit wiring diagram

Unit OperationTwo types of units are available: Mark IV/AC control units or units equipped with the new MicroTech2000 Water Source Heat Pump Controller.

Mark IV/AC Control UnitsThe Mark IV/AC control circuit has built-in night setback

operation. A “grounded’ signal to the “U” terminal on thelow voltage terminal strip puts the unit into the unoccupiedmode for night setback operation. Fan operation terminatesand unit control reverts to the night setback terminal on thethermostat, W2; day heating and cooling operation islocked out. R-W2 energizes the compressor and reversingvalve for heating operation. Night setback operation can beoverridden for two hours by toggling the fan switch (inter-mittently closing the R to O terminals) on the Deluxe AutoChangeover thermostat. Day thermostat setpoints thencontrol the heating and cooling operation. The Mark IV/ACcontrol system also accommodates load shed and shut-down operation on receipt of a “grounded” signal to the “L”and “E” terminals, respectively, on the low voltage terminalstrip.

Figure 15.

The P and C terminals of the Mark IV/AC board are usedfor pump restart. These terminals pass a voltage signalwhenever the unit compressor is turned on. This signal isdetected by a pump restart relay board providing a N.O. orN.C. set of contacts for heat pump loop circulation pumpcontrol. When used with the Loop Water Controller, therelay operation accommodates turning off circulationpumps during unoccupied periods with a safety overridedependent, at minimum, on WSHP’s need. The P and C ter-minals may be “daisy chained” between 200 units. Seepage 22.

Field supplied relays installed on the input terminals W1,W2, Y1, Y2 or G may introduce electrical noise. Never installrelay coils in series with the inputs.

ChassisGround

Unit1

Unit2

Unit3

ToAdditional

Units

TimeClock

To activate the unoccupied mode for units on the same clock schedule,a single wire can be “daisy chained” between units and simply ground-ed through the time clock contacts. The same system can also be doneto activate the load shed and unit shutdown modes by running addi-tional wires between units to ground.

Page 14 / IM 526

The Mark IV/AC circuit board is an optional control systemwith built-in features such as random start, compressortime delay, night setback, load shed, shutdown, conden-sate overflow protection, defrost cycle, brownout, andLED/fault outputs. Figure 10 shows the LED and fault out-put sequences.

The unit has been designed for operation with a 24 voltmercury bulb type wall thermostat or a microelectronic wallthermostat selected by the manufacturer. Do not operatethe unit with any other type of wall thermostat.

The 24 volt low voltage terminal strip is set up so R-G orF-G energizes the fan, R-Y1 or F-Y1 energizes the com-pressor for cooling operation, R-W1 or F-W1 energizes thecompressor and reversing valve for heating operation. Thereversing valve is energized in the heating mode. The circuitboard has a fan interlock circuit to energize the fan when-ever the compressor’s on if the thermostat logic fails to doso.

Remember the output to the wall stat can be AC currentor DC current. Terminal (R) on the wall stat can be connect-ed to terminal (R) on the PC board for AC voltage or to ter-minal (F) on the PC board for DC voltage.

AC current DC currentR to G = fan only F to G = fan onlyR to Y1 = cooling F to Y1 = coolingR to W1 = heat F to W1 = heat

The Mark IV/AC control board has a lockout circuit tostop compressor operation if any one of its safety switchesopens (high pressure switch and low pressure switch onunit sizes 024 through 060). If the low temperature switchopens, the unit will go into the cooling mode for 60 secondsto defrost any slush in the water-to-refrigerant heatexchanger. After 60 seconds the compressor is locked out.If the condensate sensor detects a filled drain pan, thecompressor operation will be suspended only in the coolingmode. The unit is reset by opening and closing the discon-nect switch on the main power supply to the unit in theevent the unit compressor operation has been suspendeddue to low temperature (freezestat) switch, high pressureswitch, or low pressure switch on unit sizes 048 thru 060.The unit does not have to be reset on a condensate over-flow detection.

The Mark IV/AC control circuit fault output sends a sig-nal to an LED on a wall thermostat. Figure 14 shows forwhich functions the fault output is “on” (sending a signal tothe LED).

Figure 14.

LEDs FaultIndication

Yellow Green Red OutputNormal Mode Off On Off OffHigh Pressure Fault Off Off Flash OnLow Temperature Fault* Flash Off Off OnCondensate Overflow On Off Off OnBrownout Off Flash Off OnLoad Shed Off Off On OffUnoccupied Mode On On Off OffEmergency Shutdown Off Flash Off On

*In heating mode only

IM 526 / Page 15

New MicroTech 2000 WSHP Controller UnitThe MicroTech 2000 WSHP unit controller is a prepro-grammed, pretested microprocessor which:

● Controls unit heating and cooling functions in responseto a wall mounted comfort sensor.

● Monitors safety controls in each heat pump andresponds accordingly.

● Monitors discharge air temperature and leaving watertemperature at each heat pump.

● Provides fan, reversing valve, and compressor opera-tion.

● Provides control outputs for boilerless system electricheat, motorized valves, fresh air damper, and other aux-iliary equipment.

● Provides operation status of all vital unit functions.

● Provides optional night setback override for tenant com-fort.

The MicroTech 2000 WSHP unit controller supports aminimum of 6 analog inputs, 4 digital inputs and 5 digitaloutputs. All input and output connections to the controllerare made using Insulation Displacement Connectors (IDC).

The controller can operate a unit as either a stand-alonedevice (for start-up, etc.) using factory programmed set-points (see table below), or preferably, as part of theMicroTech Network System through a MicroTechCommunications Gateway (MCG). On a call for constant fanoperation, the fan relay is energized. On a call for cooling,the fan is energized (if not already on) and after a time delaythe compressor contactor is energized. On a call for heat-ing, the fan is energized (if not already on) along with thereversing valve and after a time delay the compressor con-tactor is energized.

Standard lockout circuitry causes compressor lockout ifany one of its safety switches opens. In addition, when alow temperature fault occurs the unit will run in the coolingmode for 60 seconds to defrost the water to refrigerant heatexchanger coil. If the condensate sensor detects a filleddrain pan, the compressor operation will be suspended onlyin the cooling mode. The unit can be reset by either dis-connecting power at the disconnect, feeding power to theunit or by use of the Monitor™* program through the

MicroTech Network System. The unit does not have to bereset on a condensate overflow detection.

A single onboard LED gives indication of the unit statusin relation to the following:

LED on — OccupiedLED mostly off — UnoccupiedLED mostly on — Unoccupied overrideLED flashing — Fault

If the unit controller has not been assigned a logicaladdress, the intensity of the LED is low. If a logical addresshas been assigned, the LED intensity is high.

Additional status and details are available by use of theMonitor™ program and the MicroTech Network systemeither by direct connection using a portable IBM-compati-ble computer or through the system computer.

The amount of user control without the use of the net-work is dependent on the type of comfort sensor used withthe unit. The room temperature sensor is currently availablein the following configurations:

● With LED indication and tenant override

● With LED indication, tenant override and setpoint differ-ential adjustment

The LED display indicates the same conditions that theonboard LED does. The tenant override switch allows thetenant to switch from an unoccupied to an occupied com-fort setpoint for a preprogrammed period of time. The ten-ant setpoint differential adjustment allows heating and cool-ing setpoint differentials to be modified by the tenant.

*The Monitor™ program is sold as part of the MicroTechNetwork System.

This device complies with part 15 of the FCC Rules.Operation is subject to the following two conditions:1. This device must not cause harmful interference.2. This device must accept any interference received,

including interference that may cause undesiredoperation.

DESCRIPTION FACTORY PROGRAMMED SETPOINT ADJUSTABILITY RANGEOccupied Heating Setpoint 70°F (21°C) 35°-120°F (1.7°-49°C) ➀ ➄

Occupied Cooling Setpoint 74°F (23°C) 35°-120°F (1.7°-49°C) ➃ ➄

Fan - Occupied On On, Cycle, Heat, Cycle/Cool OnUnoccupied Heating Setpoint 60°F (16°C) 35°-120°F (1.7°-49°C) ➀Unoccupied Cooling Setpoint 85°F (29°C) 35°-120°F (1.7°-49°C) ➂Fan - Unoccupied Cycle On, CycleTenant Override - 1st press 1:00 Off, 0:30 - 8:00Tenant Override - 2nd press Off Off, 0:30 - 8:00Differential 2°F (1.2°C) 1°-10°F (0.6°-5.6°C) ➄Auto / Manual Auto Manual (occupied, unoccupied, fan only, off)Next Filter Change (hours) 600 100 - 5000Clock Schedule 1 Up to 32Load Shed Start Level Off Off, 1 to 7Tenant Setpoint Adjustment Off (0°F, 0°C) Off, On (3°F, 1.7°C)Low Temperature Warning 55°F (13°C) 35°F (1.7°C) — high not usedHigh Temperature Warning 95°F (35°C) Low not used — 120°F (49°C)

➀ Unoccupied heating setpoint cannot exceed high warning setpoint.➁ Occupied heating setpoint cannot exceed unoccupied heating setpoint.➂ Unoccupied cooling setpoint cannot be lower than low warning setpoint.➃ Occupied cooling setpoint cannot be lower than unoccupied cooling setpoint.➄ Occupied heating and occupied cooling setpoints must differ by at least the differential.

NOTICE

Page 16 / IM 526

The water regulating valve must be installed in the waterdischarge line with the flow direction arrow on the bodypointing toward the return well or drain.

The control capillary is connected to the refrigerant linebetween the “outside” heat exchanger and the four-waycompressor reversing valve. Insert the bushing in the flareend of the capillary. Make sure the flare nut is in the uprightposition for screw attachment to the Shrader valve.

Adjust valve in heating modeSet the wall thermostat to operating in the heating mode.With the heat pump in operation, turn the outer adjustingstem counterclockwise slowly until the temperature of thewater leaving the heat pump is 3.5-6.5°F (1.9-3.6°C) lowerthan the entering water temperature. If the entering water

Dual Acting Water Regulating Valvetemperature is above 75°F (24°C), adjust the valve until thewater leaving the valve is 5-9°F (3-5°C) lower than theentering water. Be sure to turn the stem counterclockwiseto lower the temperature of the leaving water.

Adjust valve in cooling modeSet the thermostat to operate in the cooling mode. With theheat pump in operation, turn the inner adjusting screwclockwise until the temperature of the water leaving theheat pump is 17°F (8-9°C) higher than the entering watertemperature. If the entering water temperature is above75°F (24°C), the leaving water temperature should be 8-11°F (4-6°C) higher. Be sure to turn the inner screw clock-wise to raise the temperature of the water leaving the heatpump.

Dual Acting Water Regulating Valve.Capillary Factory Installed in RefrigerationCircuit, Valve Body Field Installed inLeaving Water Line

Water-to-RefrigerantHeat Exchanger

Airside Coil

Capillary TubesReversing Valve

Compressor

Water Out

Water In

Directionof Flow

IM 526 / Page 17

Thermostat/Subbase Connection DiagramsMark IV/AC Units – Unit Sizes 007-060

Manual changeover thermostatUnit Mark IV/AC Low Voltage Terminal Strip

O W2 G W1 Y1 F E L U A P V R C

G W Y R

Thermostat

Field Wiring

Standard automatic changeover thermostat & subbase

Part No. 106069001

Unit Mark IV/AC Low Voltage Terminal Strip


G W Y Rc Rh A

Subbase

Stat Part No. 106068801

Subbase Part No. 106069101

➀

Deluxe automatic changeover thermostat & subbaseUnit Mark IV/AC Low Voltage Terminal Strip


G W1 Y1 R W2 O A

Note ➀: Optional wire for “Fault” LED on subbase.

Standard automatic & manual changeover thermostat & subbaseUnit Mark IV/AC Low Voltage Terminal Strip


G W Y Rc Rh A

Subbase



➀


Programmable electronic thermostatUnit Mark IV/AC Low Voltage Terminal Strip


Rc R C G W1 Y1 Thermostat Park No. 106068401(Honeywell Chronotherm III)



Page 18 / IM 526

Unit Sizes 070-120Standard manual & automatic changeover thermostat & subbase

Circuit 1 Mark IV/AC Low Voltage Terminal Strip




G W1 Y1 Rc Rh W2 Y2 A

➀





Rc R C G W1 Y1 Y2 W2

Deluxe automatic changeover thermostat & subbase

Programmable electronic thermostat & subbase




G W1 Y1 R W3 W2 Y2 O A


➀

Notes:➀ Optional wire for “Fault” LED on subbase.➁ W2 optional for night setback; requires grounded signal to “U” terminal.➂ Optional for two-hour override.

Pump Restart


Stat Part No. 106068901Subbase Part No. 10609101

Stat Part No. 106068701Subbase Part No. 106069301

Part No. 106068501

IM 526 / Page 19

Options on Mark IV/AC Units

Auxiliary Relay – Part No. 0003005073

Multiple Control Panel for 1 Master & 2 Slave Units – Part No. 0056794201

Multiple Control Panel for 1 Master & 1 Slave Unit – Part No. 0003005159

The auxiliary relay is to control an auxiliary deviceexternal to the unit. As illustrated, the relay con-tacts will toggle open or close when the thermo-stat energizes the fan. The relay can also be con-nected with the yellow wire to Y1 and the whitewire to W1 which toggles relay operation withcompressor operation. Note: as shown the relayresponds to thermostat operation.To use the auxiliary relay to close the N.O. con-tacts on a fault condition - wire the orange wire toA and the white wire to F.

The multiple unit control panel is an accessory topermit the control of up to four units from onethermostat.1. Control voltage of the master unit determines

the voltage of the MUCP. The electrically iso-lated dry contacts controlling the slave unitsare not voltage-sensitive.

2. Dotted lines represent low voltage (Class II)wiring; a color-coded thermostat cable is rec-ommended. The number indicates the num-ber of conductors required.

3. MUCP may be mounted horizontally or verti-cally on heat pump cabinet or any convenientsurface.

4. Do not use if Mark IV/AC night setback emer-gency shutdown or load shed logic is beingutilized.

1. Connect the four flying leads of theMaster/Slave relay board to the terminal stripof the master unit. Cap off the brown wire.

2. Locate relay board adjacent to terminal stripby letting it hang loose.

3. Wire from relay board terminal strip to the ter-minal strip of slave unit as shown.

4. Wire the wall thermostat to the terminal stripof master unit. This relay board permits con-trol of two units from a single thermostat.

5. The two control circuits are now electricallyparallel and both units will operate as one inresponse to the wall thermostat.

6. Cut fixed cool anticipator on thermostat, ifpresent.

7. The Master/Slave board requires a DC controlvoltage. Subsequently, all auxiliary circuitsmust also be wired to utilize a DC control volt-age.

Yellow

Orange

OptionalRelayBoard

1

2

3

24 Volt Terminal Strip

Y2 W2 G W1 Y1 F E L U A P V R C

COM

N.O.

N.C.

O W G W Y F E L U A P V R C2 1 1

CO

FLTLTH

PH

P

RV

RV V R C

P/N: 0567924XXMaster

Common

Fan

L1 Com

p

CO

FLTLTH

PH

P

RV

RV V R C

P/N: 0567924XXSlave

Common

Fan

L1 Com

p

RW

GY

W G Y

C

P/N: 03005159

O W G W Y F E L U A P V R C2 1 1

G W Y R W W Y O A1 1 3 2 2

Deluxe Auto ChangeoverThermostat and Subbase

RW

CY

RW

CY

RW

CY

YG

WC

OW2 G

W1

Y1 F E L U A P V R C

OW2 G

W1


OW2 G

W1


G Y1

W1

OR Y2

W3

W2

A

W

G

Y

Mark IVTerminal

Strip

Mark IVTerminal

Strip

Mark IVTerminal

Strip

P/N 0567924XXUnit No. 1



Deluxe Auto ChangeoverThermostat and Subbase

P/N

056

7942

01

BL BK GN

Relay

BL

BK

BL

1

2

3

GN BL OR YE WH

R C V Y1 W1

ORYEWH

PC Board Terminal Strip

Receptical

5 4 3 2 1

OR RD

CompressorContactor(Circuit 1)

Splice Conn.

Com

Com

p

(On Circuit 1 Mark IV Board)

RD

OR

6 3 1

BL BK GN

Relay

BL

BL

BK

1

2

3

GN BL OR YE WH

R C V Y1 W`

ORYEWH

Low Voltage Terminal Strip

631

Blue to 6

Black to 3White to 1

PlugPins,Female

Conduit

Anti-ShortBushing

Connector

Valve 36" (915 mm)Lead Length

12345

Orange to 5

Pin, Male

Plug

Conduit

Anti-ShortBushing

66" (1676 mm)Lead Length

11/4" or 11/2" Valve

Black to 1Red to 2White to 3Yellow to 4

Page 20 / IM 526

Motorized Valve & Relay for Unit Sizes 007 thru 060Relay Part No. 0059004354

Motorized Valve & Relay for Unit Sizes 070 Thru 120Relay Part No. 0061201202

Typical Motorized Valve Installation Manual Override TimerPart No. 0002005717 (1 Hr.)

and 0002005718 (6 Hr.)One wire is daisy chained to each heat pump “U” terminalto activate night setback operation. An override timer wiredin the night setback circuit, per the diagram below, takesthe unit out of night setback operation by opening the nightsetback circuit. The manual timer contacts are closed whentimed out and open when turned to the timing position. Theoverride timer is available in 1 or 6 hour timing.

Valve opens when compressor is on and closes when compressor is off. If Mark IV/ACnight setback emergency shutdown or load shed logic is being utilized, the valve will cycleopen and closed in response to a call for heating and cooling at day thermostat set points.Valves for unit sizes 007 thru 019 are 1⁄2", power open-spring return; 3⁄4" valves for unitsizes 024 thru 060 are power open-power close type.

Valve opens when compressor is on and closes when compressor is off. If Mark IV/ACnight setback emergency shutdown or load shed logic is being utilized, the valve will cycleopen and closed in response to a call for heating and cooling at day thermostat set points.These 11⁄4" and 11⁄2" valves are power open-power close type.

ChassisGround

ToAdditional

Units

TimeClock

U U U

Open = OccupiedClosed = Unoccupied

ManualTimer

Unit1

Unit2

Unit3

To Low VoltageHole on Unit

Shutoff Valve

To Main System

Conduit Assembly

Motorized ValveAssembly

Flexible Hose

Return Water Connection

This diagram assumes you are usingan AC signal source for thermostatwiring.

This diagram assumes you are usingan AC signal source for thermostatwiring.

OR

Back-up Heat Option

Heat (W)(Power)

Load Shed InLoad ShedOut

DuctHeaterControl

N.O.

N.O.

4 5 1 2

DCCommon

Water Temp.Sensor

SignalInverterAssy.

W1

L

V

F

RD

BR

GR

WHOhm

Keystone RL-2010-1726-97-DIor Equivalent

4

1

3

2

WH

BK

WH

GN

RD

T

Dual CircuitUnits

BSK for Dual Circuit Heatpump

Dual & Single CircuitUnits

W1

L

F

R1

R1

Boilerless SystemPart No. 0062522201 (Sizes 007 Thru 042)

or Part No. 0062522204 (Sizes 048 Thru 060)These field installed kits are supplied with sheet metalenclosure, wire harness and printed circuit boards. Attachthe sheet metal enclosure on the unit per the diagrambelow. Route the wire harness through the knockout(s) andconnect per the wiring diagrams.

Note: Consult factory before attempting to use thisaccessory on units which utilize the Mark IV/AC night set-back, emergency shutdown and/or load shed logic circuits

The BSK option provides a separate circuit board whichis added to the heat pump to provide control of a ductheater. The duct heater must be complete with a 24 voltcontrol circuit, requiring only closure of a set of contacts foroperation.

The BSK control consists of a circuit board with SPDTrelay, Normal/Override selector switch, a potentiometer forselecting changeover temperature, and control logic com-ponents. A temperature sensor is fastened to the inlet waterline of the heat pump.

When the low voltage wall thermostat (not included)requires the heat pump to operate in the heating mode, theinlet water line temperature is monitored, and control logicdetermines whether or not the water temperature is ade-quate to permit heat pump heating. On a temperature dropto the selected control point, the duct heater will be substi-

tuted for the compressor. The heater and the compressornever operate simultaneously.

When the thermistor temperature is less than the poten-tiometer setpoint, the relay will be cycled by the heatdemand of the thermostat. Additionally, control logic willsuspend compressor operation.

Fan operation may be either continuous or cycled withheating operation, as selected by the fan switch of the ther-mostat.

On a space temperature rise, when the thermostat callsfor cooling operation, the BSK permits compressor opera-tion, regardless of inlet water temperature or selectorswitch position.Note: This is a D.C. voltage control option and the wall statmust also be wired for D.C. operation by using the terminal(F) form the P.C. board to the wall thermostat.

9.66(245 mm)

(007 – 042)

14.50(368 mm)

(048 – 060)

6.5 (165 mm) (007 – 042)4.12 (105 mm) (048 – 060)

1.75(44.5 mm)

IM 526 / Page 21

Page 22 / IM 526

Pump Restart Relay Kit #0061419001For Installation in the Loop Water Controller

Pump Restart Relay Kit #0061419001For Installation in a Water Source Heat Pump Kit

Operation: The pump restart relay is designed to work withthe Mark IV/AC board’s P and C terminals for sensing com-pressor operation. Any Mark IV/AC board can energize thepump restart relay and change the state of the normallyopen and normally closed contacts. A contact closurebetween Loop Water Controller terminals 58 and 64 willrestart the loop circulating pump during unoccupied timeperiods.

Installation: Install the pump restart relay in the Loop WaterController. First connect the wiring from the relay to theLWC terminals. Run the wires through the LWC-side panelto the P and C terminals of the Mark IV/AC boards. Removethe cover of the double faced tape and affix the tapedbacks of the relay to the bottom floor of the LWC paneladjacent to the pushbutton circuit breaker CB1 and termi-nal block TB3.

Operation: The pump restart relay is designed to work withthe Mark IV/AC board’s P and C terminals for sensing com-pressor operation. Any Mark IV/AC board can energize thepump restart relay and change the state of the normallyopen and normally closed contacts. A contact closurebetween Loop Water Controller terminals 58 and 64 willrestart the loop circulating pump during unoccupied timeperiods.

Installation: Install the pump restart relay in any one of the200 heat pump units with Mark IV/AC printed circuit boardcontrols. Wire the relay to the Mark IV/AC board terminals P,R and C. Run the P and C wires out the side of the heatpump unit for connection to (daisy chain) the P and C ter-minals of the other Mark IV/AC board heat pump units.Place the relay anywhere in the heat pump unit control boxaway from any other terminals and wiring. In some cases,the relay can be affixed to a flat surface by removing thedouble faced tape on the back surface of the relay.

W2O G W1 T1 F E L U A P V R C

7

6

5

4

3

2

1 65

58

64

24 Volt Terminal Strip — Mark IV/AC Board

Daisy Chain To OtherMark IV/AC Boards

LWC Terminal, 24 Volt

LWC Terminal, Pump Restart Input

LWC Terminal, 24 Volt (Earth Ground)

PumpRestartRelay

(Jumper Terminals1 to 7 and 5 to 6)

W2O G W1 T1 F E L U A P V R C

7

6

5

4

3

2

1

58

64

24 Volt Terminal Strip — Mark IV/AC Board

Daisy Chain To OtherMark IV/AC Boards

LWC Terminal, 24 Volt

LWC Terminal, Pump Restart Input

PumpRestartRelay

(Jumper Terminals1 to 7)

Field Installed Options on MicroTech 2000 Units

IM 526 / Page 23

Standard OptIons Code1. Timed Output Relay . . . . . . . . . . . . . . . . . . . . . . MTR2. Boilerless System Relay . . . . . . . . . . . . . . . . . . MBS3. Fresh Air Damper . . . . . . . . . . . . . . . . . . . . . . . MFD4. Motorized Valve Relay . . . . . . . . . . . . . . . . . . . . MTV

Note: The 4th option not available on sizes 070 through120.

If only one option is required in a unit, it will be supplied bythe WSHP Base Controller. This can be any one of the fourstandard options. If more than one is desired, the second,third, and fourth options will be supplied by the auxiliarymodule; these can be any combination of the standardoptions listed above.

Terminal Boards(On Side Panel of Unit)

1

1

2

2

3

3

4

4

5

5 6 7 E L U P C

WHO1

YE03

Relay24 VAC

CoilSPDT RD

02

OR04

1234

Relay24 VAC

CoilSPDT

Auxiliary OptionJ7

BL14

YE12

WH10

By Others

24 VAC

1

2

3 4

5

OR08

RD11

1234

Relay24 VAC

CoilSPDT

Auxiliary OptionJ10

BL19

YE17

WH15

By Others

24 VAC

1

2

3 4

5

OR18

RD16

1

1

2

2

3

3

4

4

5Relay24 VAC

CoilSPDT

Auxiliary OptionJ6

BL09

YE07

WH05

OR08

By Others

24 VAC

RD06

1st option (field installed) 2nd option (field installed)

3rd option (field installed) 4th option (field installed)

Page 24 / IM 526

Maintenance

Troubleshooting

1. Normal maintenance on all conditioners is generally lim-ited to filter changes. Motors used with WSHP unit size007 through 060 are provided with permanently lubricat-ed motors and require no oiling even though oil capsmay be provided. Larger sizes 070, 090 and 120 withcaps should be oiled in accordance with the oil label oneach heat pump.

2. Filter changes are required at regular intervals. The timeperiod between changes will depend upon the projectrequirements. Some applications such as motels pro-duce a lot of lint from carpeting and linen changes, andwill require more frequent filter changes. It is suggestedthat the filter be checked at 60-day intervals for the firstyear until experience is acquired. If light cannot be seenthrough the filter when held up to sunlight or a brightlight, it should be changed. A more critical standard maybe desirable.

3. The condensate drain pan should be checked annuallyand cleaned and flushed as required.

4. Recording of performance measurements of volts,amps, and water temperature differences (both heatingand cooling) is recommended. A comparison of loggeddata with start-up and other annual data is useful as anindicator of general equipment condition.

5. Periodic lockouts almost always are caused by air orwater problems. The lockout (shutdown) of the condi-tioner is a normal protective result. Check for dirt in thewater system, water flow rates, water temperatures, air-flow rates (may be dirty filter), and air temperatures. If thelockout occurs in the morning following a return fromnight setback, entering air below machine limits may bethe cause.

Should a major problem develop, refer to the following information for possible cause and corrective steps.

7. The internal winding of the compressor motor may begrounded to the compressor shell. If so, replace thecompressor.

8. The compressor winding may be open. Check continuitywith ohmmeter. If the winding is open, replace the com-pressor.

Compressor attempts to start but doesn’t1. Check capacitor.

2. Check for defective compressor by making resistancecheck on winding.

3. Check run capacitor.

Compressor runs in short cycle1. Check thermostat mounting and location.

2. Check all relays, relaying and contacts.

3. Check run capacitor.

4. Check high pressure switch.

5. Check low temperature switch.

6. See if reversing valve has not fully shifted to either side.

Insufficient cooling or heating1. Check thermostat for improper location.

2. Airflow may be insufficient. Check and clean the filter.

3. The reversing valve may be defective, creating a bypassof refrigerant. If the unit will not heat, check the revers-ing valve coil.

4. Check capillary tubes for possible restriction of refriger-ant flow.

5. Check for restriction in water flow.

Neither fan nor compressor run1. The fuse may be blown or the circuit breaker is open.

Check electrical circuits and motor windings for shortsor grounds. Investigate for possible overloading.Replace fuse.

2. Wires may be loose or broken. Replace or tighten.

3. Supply voltage may be too low. Check it with thepower company.

4. Control system may be faulty. Check thermostat forcorrect wiring and check 24 volt transformer forburnout.

Fan operates but compressor does not1. Check capacitor.

2. Wires may be loose or broken. Replace or tighten.

3. The high pressure may have tripped due to:a. Fouled or plugged condenser.b. Lack of or no condenser water.c. Too warm condenser water.d. Not enough airflow over the coil due to dirty filters.e. Coil or fan motor failure.

4. The low temperature switch may have tripped due to:a. Fouled or plugged condenser.b. Lack of or no condenser water.c. Too cold condenser water.d. Not enough airflow over the coil due to dirty filters.e. Coil or fan motor failure.

5. Check thermostat setting, calibration and wiring.

6. The compressor overload protection is open. If the com-pressor dome is extremely hot, the overload will notreset until cooled down. If the overload is external,replace it. If the overload is internal, replace the com-pressor.

IM 526 / Page 25

Insufficient water flow through condenser1. Check to see that valves are open all the way.

2. Check for air in lines.

3. Check circulating pump.

Water drips from conditioner1. Check for plugged condensate drain.

2. Check for dirty filter.

3. Check to see if condensate drain runs uphill.

4. See if blower motor is up to speed.

5. Check for loose or mispositioned blower.

6. Are drains properly trapped?

Noisy unit operation1. Check for fan wheel hitting the housing. Adjust for clear-

ance.

2. Check for bent fan wheel. Replace if damaged.

3. Check for loose fan wheel on shaft. Tighten.

4. Make sure compressor is floating free on its isolatormounts.

5. Check for tubing touching compressor or other surface.Readjust tubing by bending slightly.

6. Check screws on all panels. Tighten.

7. Check for chattering or humming in the contactor relaysdue to low voltage or a defective holding coil. Replacecomponent.

8. Check water balance to unit for proper water flow rate.

Page 26 / IM 526

Product Warranty

Optional Warranties

McQuay International, herein referred to as the “Company,”warrants to the original owner that each water-to-air heatpump is free from defects in material and workmanship.Any part or portion thereof (except air filters if of the throw-away type) which becomes defective under normal use dur-ing the period of this warranty will be repaired or replacedprovided the Company’s examination shall prove to its sat-isfaction that the part was or became defective under nor-mal use. This warranty contemplates that first year mainte-nance labor was arranged for with the installer or otherwiseat the time the conditioner was purchased or installed. TheCompany’s obligations under this warranty are limited to:(a) repairing the defective part or (b) furnishing a replace-ment part provided the defective part is returned to the fac-tory, transportation charges prepaid. No reimbursement willbe made for expenses incurred in making field adjustmentsor replacements unless specifically authorized in writing bythe Company.

To obtain assistance under the parts warranty or extend-ed motor-compressor warranty, simply contact the sellingagency. To obtain information or to gain factory help, con-tact McQuay International, Warranty Claims Department,P.O. Box 1551, 13600 Industrial Park Blvd., Minneapolis,MN 55440; telephone (612) 553-5330.

This warranty constitutes the buyer’s sole remedy. Itis given in lieu of all other warranties. There is noimplied warranty of merchantability or fitness for a par-ticular purpose. In no event and under no circumstanceshall the company be liable for incidental or conse-quential damages, whether the theory be breach of thisor any other warranty, negligence, or strict tort.

No person (including any agent, salesman, dealer or dis-tributor) has authority to expand the Company’s obligationbeyond the terms of this express warranty, or to state thatthe performance of the product is other than that publishedby the Company.

One-Year Warranty On Entire Conditioner

One-Year Refrigeration Circuit WarrantyHermetically sealed motor-compressor assemblies and allcomponents of refrigeration circuits not readily separabletherefrom are warranted to the original owner for one year.Refrigerating circuits consist of the motor-compressorassembly, evaporator coil, condenser coil, and intercon-necting tubing. Repairs under this warranty will be made atthe Company’s expense provided that the refrigerating cir-cuit is delivered, without shipping damage, transportationprepaid, to the factory or to a factory designated repair sta-tion, at the Company’s option. This one-year warranty doesnot include any other parts of the equipment such as filters,fans, fan motors, control, cabinet parts, electric relays,capacitors, protective devices, or wiring. The Company is

not obligated under this warranty for field labor such asservice for inspection, removing, packing and/or rein-stalling the refrigeration circuit, nor for return transporta-tion charges.

If the hermetically sealed circuit contains a defect atthe time of initial start-up that requires delivery of theconditioner to the Company or a factory designatedrepair station, the contractor performing initial start-up ofthe conditioner may be eligible to received a fixedallowance. The contractor should contact the localCompany representative for information concerning thisfixed allowance.

General ConditionsThe above warranties are void if the Company’s equipmenthas been damaged, misused, subjected to abnormal use orservice or if its serial number has been altered, defaced orremoved, or payment for the equipment is in default. TheCompany is not responsible for service to correct condi-tions due to misapplication, improper installation, inade-quate wiring, incorrect voltage conditions or unauthorizedopening of the refrigeration circuit, operation at abnormaltemperatures and water flow rates, operation on an opencondenser water circuit, nor for consequential damages. In

case the Company’s equipment is installed in conjunctionwith cabinets, grilles, louvers, controls or other parts man-ufactured by others, these warranties shall apply only to theCompany manufactured portion of the equipment. The con-ditions of the warranty plan are effective for eighteen (18)months from date of factory shipment. The Companyreserves the right to make a handling and inspection chargein the case of parts or equipment improperly returned asdefective and/or as being in warranty.

2nd to 5th year refrigerant circuit warrantyHermetically sealed motor-compressor assemblies and allcomponents or refrigerating circuits not readily separabletherefrom are warranted to the original owner for use forfour additional years. Refrigerating circuits consist of themotor-compressor assembly, evaporator coil, condensercoil and interconnecting tubing. Repairs under this warran-ty will be made at the Company’s expense provided that therefrigerating circuit is delivered, without shipping damage,

prepaid, to the factory or to a factory designated repair sta-tion, at the Company’s option. This warranty does notinclude any other parts of the equipment such as filters,fans, fan motors, controls, cabinet parts, electrical relays,capacitors, protective devices, or wiring. The Company isnot obligated under this warranty for field labor such as ser-vice for inspection, removing, packing and/or reinstallingthe refrigeration circuit, nor for return transportationcharges.

The conditions of this warranty plan are effective forsixty-six (66) months from date of factory shipment. TheCompany reserves the right to make a handling and inspec-tion charge in the case of parts or equipment improperlyreturned as defective and/or as being in warranty.

Optional 2nd to 5th yearcompressor warrantyThe hermetically sealed motor-compressor is warranted tothe original owner for four (4) additional years. Compressorsunder this warranty will be supplied at the Company’sexpense provided the failed compressor is returned, trans-

portation prepaid, to the factory. This warranty does notinclude any other parts of the equipment such as fans, fanmotors, controls, cabinet parts, electrical relays, capacitors,protective devices, or wiring. The Company is not obligatedunder this warranty for field labor such as service forinspection, removing, packing and/or reinstalling the refrig-eration circuit, nor the return transportation charges.

The conditions of this warranty plan are effective forsixty-six (66) months from date of factory shipment. TheCompany reserves the right to make a handling and inspec-tion charge in the case of parts or equipment improperlyreturned as defective and/or as being in warranty.

AAF-McQuay Incorporated4900 Technology Park Boulevard, Auburn, New York 13021-9030 USA (315) 253-2771

Printed on recycled paper containing at least 10% post-consumer recycled material.©1999 AAF-McQuay Incorporated

IM 526 (Rev. 12/99)

Notes

Documents

Horizontal Water Source Heat Pump Units