S12 SEQUENCER™ - RBITable 4: Parameter Listing for staging applications. 1300 Midway Blvd., Mississauga, Ontario L5T 2G8 Tel.(905) 670-5888 Fax (905) 670-5782 260 North Elm Street,

SS1122 SSEEQQUUEENNCCEERR™™

OOPPEERRAATTIINNGGMMAANNUUAALL

1300 Midway Blvd., Mississauga, Ontario L5T 2G8Tel. (905) 670-5888 Fax (905) 670-5782260 North Elm Street, Westfield, MA 01085Tel. (413) 568-9571 Fax (413) 568-9613www.rbiwaterheaters.com

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SS1122 SSeeqquueenncceerr -- 11 -- OOppeerraattiinngg IInnssttrruuccttiioonnss

Figure 1: S12 Sequencer Front Panel

IInnttrroodduuccttiioonn::

The SS1122 SSeeqquueenncceerr™™ is a single zone, modulation or staging boiler controller. Itprovides complete control for a typical single zone 3 way valve, domestic hot water ORheating system, including system circulators and combustion air dampers in onesingle, compact package. State of the art electronic hardware and control techniquesallow for accurate, fully automatic system control while saving on operating costs.


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FFuunnccttiioonn::

For heating zone applications, the SS1122 SSeeqquueenncceerr™™ acts as an indoor / outdoor resetcontroller. It senses the OOuuttddoooorr temperature and calculates the TTaarrggeett indoortemperature from a reset schedule. The SS1122™™ then modulates the valve or turns boilerstages on and off, as necessary, to ensure that the IInnddoooorr temperature reaches theTTaarrggeett temperature. The IInnddoooorr temperature sensor is installed in the return waterline for staging applications, or the supply water line for modulating valve applications.The OOuuttddoooorr temperature sensor is located on a north wall, away from any influenceof the sun or any other heat source.

For domestic hot water applications, the SS1122™™ acts as a constant temperaturecontroller. The TTaarrggeett indoor temperature remains constant, set to the desireddomestic hot water tank temperature. Boiler stages are then turned on and off, asnecessary, to ensure that the IInnddoooorr temperature reaches the TTaarrggeett temperature. TheIInnddoooorr temperature sensor is installed in the domestic hot water tank and the OOuuttddoooorrtemperature sensor is not used.

PPaanneell DDiissppllaayy::

The Panel Display screen of the SS1122™™ consists of 5 characters. The rightmostcharacter is the DDiissppllaayy MMooddee. It is used to describe the current value displayed. Alltemperatures and PPaarraammeetteerrss (control settings) can be displayed using the followingoperating modes:

1. UUnnaatttteennddeedd ((ccyycclliiccaall ddiissppllaayy)) mmooddee: When left unattended for a period of 1minute, the screen reverts to a cyclical display mode showing the following:

PPaarraammeetteerr DDiissppllaayyeedd SSaammppllee SSccrreeeenn PPrreessssiinngg tthhee AAddjjuussttbbuuttttoonnss ......

Outdoor temperature - i5 0Changes the Targettemperature value.

Indoor temperature i64 IChanges the Targettemperature value.

Target temperature i70 =Changes the Targettemperature value.

Table 1: Unattended display mode screens.


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PPaanneell DDiissppllaayy:: (cont’d)

1. UUnnaatttteennddeedd ((ccyycclliiccaall ddiissppllaayy)) mmooddee (cont’d):

If any of the Adjust buttons are pressed while any of the above temperatures aredisplayed, the Panel Display immediately reverts to show the Target temperature.As the button is pressed again, the left character of the display shows the letter “c”(eg. c. I70 = ), indicating that further pressing of the Adjust button will “change”the current Target temperature. As the button is pressed again, the Targettemperature is changed up or down, depending on the Adjust button pressed.WWhheenn tthhee cchhaannggee iiss ccoommpplleettee,, tthhee DDiissppllaayy MMooddee bbuuttttoonn mmuusstt bbee pprreesssseedd,, jjuusstt lliikkeeaann ““eenntteerr”” kkeeyy,, ffoorr tthhee nneeww vvaalluuee ttoo bbee aacccceepptteedd aass tthhee nneeww TTaarrggeett tteemmppeerraattuurree..As soon as the Display Mode button is pushed, the leading “c” disappears(eg. I60 = ) and the Target temperature takes on the new displayed value. At thispoint, the Display Panel reverts to the Manual display mode described below.

Certain overriding conditions will also affect the left-most character of the Targettemperature display as shown below. For further information, refer to theParameter Definitions section of this manual.

OOvveerrrriiddiinngg CCoonnddiittiioonn SSaammppllee SSccrreeeennNormal Operation: Target temperature not overridden. I60 =Target temperature in “change” mode. c. I63 =Outdoor Cutoff Temperature: All boilers are off / valve closed. o. 73 =High Temperature Limit: Target temperature will not exceedthis value. H. 200 =Low Temperature Limit: Target temperature will not go belowthis value. L. I05 =

Table 2: Target temperature display variations.


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2. MMaannuuaall ddiissppllaayy mmooddee: By sequentially depressing the DDiissppllaayy MMooddee button, thefollowing can be displayed in a cyclic fashion:

PPaarraammeetteerr DDiissppllaayyeedd SSaammppllee SSccrreeeenn PPrreessssiinngg tthhee AAddjjuussttbbuuttttoonnss ......

Outdoor temperature - i5 0 Has no effect.

Indoor temperature i64 I Has no effect.

Target temperature i70 =Changes the Targettemperature value.

Remaining Hours untilLead Boiler change h. 40 r Has no effect.

One of the control Parameterscreens (see list below) d. I00 P

Displays previous or nextParameter.

Table 3: Manual display mode screens.

Pressing the Adjust buttons while the Target temperature is displayed, changes theTarget temperature value as described in the Unattended (cyclical display) modeabove.

3. PPaarraammeetteerr ddiissppllaayy // eeddiitt mmooddee: Pressing the Adjust buttons1 while the Parameterscreen is displayed, places the Panel Display in Parameter display mode. In thismode, the first (left most) 2 characters of the screen describe the parameter beingdisplayed. The Adjust buttons are used to view the various different Parameters.As the Up Adjust button is pressed, the next Parameter (down the table) isdisplayed; as the Down Adjust button is pressed, the previous Parameter (up thetable) is displayed. Note that this display is not cyclical, ie. when the firstParameter is displayed, pressing the Down Adjust button will not have any effect.A summary of all Parameters follows.

1{Note: If the S12 is equipped with the KEY option, then the S12 KEY needs to be inserted (refer to Fig.2) in order for the Adjust buttons to function. Without the KEY, the Display Mode button can still beused to view the control’s operating temperatures, however, no control setting changes are allowed}.


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3. PPaarraammeetteerr ddiissppllaayy //eeddiitt mmooddee (cont’d):

SSttaaggiinngg PPaarraammeetteerr AAddjjuusstt LLiimmiittss SSaammppllee SSccrreeeennLead boiler 1 to (number of boilers) lb. i PDay Set point -35 to 220�F d. i00 PNight Set point -35 to 220�F n. 90 PRatio - Indoor 0 to 15 ri. 1 PRatio - Outdoor 1 to 15 ro. 1 PLow limit of Target temperature -34�F to (High limit - 1) L. I20 PHigh limit of Target temperature (Low limit + 1) to 220�F H. 200 POutdoor Cutoff temperature 32 to 99�F oc. 65 POutdoor Cutoff deadband 0 to 15�F od. 5 PThrottling degrees between stages 0 to 15�F SO. 5 PDeadband between stages 0 to (Throttling - 1)�F db. 3 PNumber of boilers (stages) 1 to 12 nb. 8 PLead boiler change period 1 to 255 hours h. I00 PLead boiler auto-increment 0 to (no. of boilers -1) AI. I POutdoor sensor calibration Current Outdoor reading +/- 15�F. O. 25 PIndoor sensor calibration Current Indoor reading +/- 15�F. I. I65 PDisplay units �F or �C OF PLead pump change period 0 to 255 hours c. I00 PNumber of pumps 1 to (12 - no. of boilers) nP. 2 PLead Pump 1 to (no. of pumps) LP. I P

Service Parameters View only RESERVED values

Table 4: Parameter Listing for staging applications.


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3. PPaarraammeetteerr ddiissppllaayy //eeddiitt mmooddee (cont’d):

To change the value of any Parameter, using the Adjust buttons, display the desiredparameter on the Panel Display. Press the Display Mode button once - the letter“P” (the rightmost character of the screen) will start flashing1. Use the Adjustbuttons to change the value of the Parameter. When the change is complete, theDisplay Mode button must be pressed again, just like an “enter” key, for the newvalue to be accepted as the new Parameter value. As soon as the Display Modebutton is pushed, the letter P will stop flashing. At this point, the Panel Displayautomatically reverts back to Manual display mode, ie. if the Display mode buttonis pressed again, the Outdoor temperature will be displayed (refer to Table 3above).

1{Note: If this does not occur, the Panel Display is still in Manual display mode. Continue tosequentially press the Display mode button until the Parameter screen is shown. Press the Up orDown Adjust button to display the next or previous Parameter. At this point, the Panel Display is inParameter display mode. The Adjust buttons can be used to display the desired Parameter and theDisplay Mode button will act as an “enter” key}.

To exit Parameter display mode and go back to Manual display mode, press theDisplay mode button twice in succession.


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Figure 2: S12 Wiring Diagram


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PPaarraammeetteerr DDeeffiinniittiioonnss::

1. OOuuttddoooorr TTeemmppeerraattuurree:: The current temperature at the sensor wired in the“Outdoor sensor” wiring location between the “+” and “I2" terminals - refer towiring diagram in Figure 2. The Outdoor sensor is typically used for heating systemapplications only. It should be located on a north wall, away from any heat sourceslike exhaust fan hoods or mechanical room relief air openings.

2. IInnddoooorr TTeemmppeerraattuurree:: The current temperature at the sensor wired in the “Indoorsensor” wiring location between the “+” and “I1" terminals - refer to wiringdiagram in Figure 2.

a. For heating system applications, the Indoor sensor should be installed in thereturn water line, ie. the water pipe coming back from the building, before itenters the boilers.

b. For domestic hot water applications, the Indoor sensor should be located on thedomestic hot water tank, approximately one third up from the bottom.

3. TTaarrggeett TTeemmppeerraattuurree: The desired temperature that the SS1122™™ is attempting tomaintain the Indoor sensor temperature at.

a. For heating system applications, the Target temperature is calculated using theDay Set Point (or Night Set Point - depending on the state of the “NightSetback” input across terminals “I4" and “GND”), Ratio - Indoor and Ratio -Outdoor parameter values as well as the current Outdoor temperature.

b. For domestic hot water applications, the Target temperature equals the Day SetPoint (or Night Set Point - depending on the state of the “Night Setback” input).The Ratio parameters and Outdoor temperature are ignored.

c. Refer to Figures 3, 4 & 5 for illustration.


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Figure 3: Effect on Target temperature from Set Point changes

Figure 4: Effect on Target temperature from Ratio changes


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Figure 5: Target temperature graph


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SSttaaggiinngg CCoonnttrrooll PPaarraammeetteerr DDeeffiinniittiioonnss::

1. LLeeaadd bbooiilleerr ((““LLbb”” ppaarraammeetteerr)): The desired ssttaaggee number to be turned on first,when heat is required. This parameter can be used to make any of the boilers inthe system, lead boiler. The Combustion Air Damper cycles on/off with the leadstage.

2. DDaayy SSeett PPooiinntt ((““dd”” ppaarraammeetteerr)): The desired Target temperature when the outdoortemperature is 70�F/21�C. This value is used to calculate the Target temperaturewhen in Day mode - ie. an open circuit at the “Night Setback” input acrossterminals “I4" and “GND”). As the outdoor temperature drops from 70�F/21�C, theSS1122™™ will raise the Target temperature according to the Ratio - Indoor and Ratio -Outdoor parameters. Refer to Figure 3.

3. NNiigghhtt SSeett PPooiinntt ((““nn”” ppaarraammeetteerr)): Same as the Day Set Point. This value is usedinstead of the Day Set Point when in Night mode - ie. a short circuit at the “NightSetback” input across terminals “I4" and “GND”).

4. RRaattiioo -- IInnddoooorr ((““rrII”” ppaarraammeetteerr)): The indoor quantity of the slope of the outdoorreset curve calculation. This parameter is used in conjunction with the Ratio -Outdoor parameter to describe how responsive the control is to changes in outdoortemperature. Eg. For every “rO” degrees drop in outdoor temperature, the controlwill raise the Target water temperature by “rI” degrees. Similarly, for every “rO”degrees rise in outdoor temperature, the control will drop the Target watertemperature by “rI” degrees. For constant water applications, set “rI” to 0.

5. RRaattiioo -- OOuuttddoooorr ((““rrOO”” ppaarraammeetteerr)): The outdoor quantity of the slope of theoutdoor reset curve calculation. Refer to the example in the “rI” parameterdefinition above. Refer to Figure 4.

6. LLooww lliimmiitt ooff TTaarrggeett tteemmppeerraattuurree ((““LL”” ppaarraammeetteerr)): The lowest value that the Targettemperature is allowed to drop to. Note that when the outdoor temperature issufficiently hot not to require heat (ie. Outdoor Cutoff mode), all stages will still gooff. This parameter is most useful to prevent boilers from operating below theircondensating temperatures, typically 110�F/43�C to 160�F/71�C, depending on theboiler manufacturer. Please refer to the boiler manufacturer’s specification for thecorrect low operating limit for the application. When the Target temperature lowlimit is reached, an “L” appears to the left of the Target temperature value.


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SSttaaggiinngg CCoonnttrrooll PPaarraammeetteerr DDeeffiinniittiioonnss:: (cont’d)

7. HHiigghh lliimmiitt ooff TTaarrggeett tteemmppeerraattuurree ((““HH”” ppaarraammeetteerr)): The highest value that theTarget temperature is allowed to rise to. This parameter is most useful toprevent boilers from operating above a desired limit, eg. prevent scalding bylimiting the domestic hot water tank temperature. When the Targettemperature high limit is reached, an “H” appears to the left of the Targettemperature value. Refer to Figure 5.

8. OOuuttddoooorr CCuuttooffff tteemmppeerraattuurree ((““oocc”” ppaarraammeetteerr)): The outdoor temperature limitabove which all heating is disabled. When the outdoor temperature issufficiently hot not to require the heating system to operate (ie. outdoortemperature > “oc” temperature), the Main Pump(s), Combustion Air Damperand all boiler stages are turned off. When in Outdoor Cutoff mode, an “o”appears to the left of the Target temperature value. Refer to Figure 5.

9. OOuuttddoooorr CCuuttooffff ddeeaaddbbaanndd ((““oodd”” ppaarraammeetteerr)): The number of degrees theoutdoor temperature has to drop below the Outdoor Cutoff temperature beforethe heating is enabled. When the outdoor temperature is sufficiently cool torequire the heating system to operate (ie. outdoor temperature <= “oc” - “od”),the Main Pump(s) are turned on and the boiler stages and Combustion AirDamper are operated as required. When heating is enabled, no characterappears to the left of the Target temperature value.

10. TThhrroottttlliinngg ddeeggrreeeess bbeettwweeeenn ssttaaggeess ((““SS��”” ppaarraammeetteerr)): The number of degreesthe indoor temperature has to drop before the next heating stage is turned on.This parameter should be set to the maximum temperature rise capability of allthe boiler stages divided by the number of stages, eg. if 4 boiler stages are ableto raise the return water temperature by 20�F, then set “S�” to 5.

11. DDeeaaddbbaanndd bbeettwweeeenn ssttaaggeess ((““ddbb”” ppaarraammeetteerr)): The minimum number of degreesover which the same boiler stage can be turned on and off. This parameter isused to prevent the boiler stages from cycling on/off too rapidly. Typically, “db”should be set to 1-3�F.


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12. NNuummbbeerr ooff bbooiilleerr ssttaaggeess ((““nnbb”” ppaarraammeetteerr)): The total quantity of heating ssttaaggeessavailable in the heating system. Eg. If a heating system has 4 two stage boilers,then set “nb” to 8 (4x2).

13. LLeeaadd bbooiilleerr cchhaannggee ppeerriioodd ((““hh”” ppaarraammeetteerr)): The actual number of hours thelead boiler has to operate / run before the lead is changed. This parameter isused to operate each and every boiler as lead. This allows all boilers to taketheir turn at being lead, thus providing even wear on all equipment.

14. LLeeaadd bbooiilleerr aauuttoo--iinnccrreemmeenntt ((““AAII”” ppaarraammeetteerr)): The number of stages per boilerin the system. When the lead boiler is changed automatically, “Lb” isincremented by “AI” to make the next boiler lead. Eg. If a heating system has4 two stage boilers then set “AI” to 2. In this manner, the “Lb” parameter willsequentially make stages 1, 3, 5 and 7 lead.

15. OOuuttddoooorr sseennssoorr ccaalliibbrraattiioonn ((““OO”” ppaarraammeetteerr)): This is the current reading of theoutdoor temperature. By using the Adjust buttons, the outdoor temperaturereading can be changed by +/- 15�F.

16. IInnddoooorr sseennssoorr ccaalliibbrraattiioonn ((““II”” ppaarraammeetteerr)): This is the current reading of theindoor temperature. By using the Adjust buttons, the indoor temperaturereading can be changed by +/- 15�F.

17. DDiissppllaayy uunniittss: This parameter serves to change the temperature units of thePanel Display. Both �F and �C are supported.

18. LLeeaadd ppuummpp cchhaannggee ppeerriioodd ((““cc”” ppaarraammeetteerr)): The actual number of hours thelead pump has to operate / run before the lead is changed. This parameter isused to operate each and every main pump as lead. This allows all pumps totake their turn at being lead, thus providing even wear on all equipment.


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19. NNuummbbeerr ooff ppuummppss ((““nnPP”” ppaarraammeetteerr)): The total quantity of main circulatingpumps (not individual boiler circulators) available in the heating system. Notethat the wiring diagram in Figure 2 shows two possible wiring locations for themain pumps.

a. For systems with oonnee ppuummpp, set “nP” to 1 and wire the pump using relayterminals “1” and “1” bbeellooww tthhee tteemmppeerraattuurree sseennssoorr tteerrmmiinnaallss (not the boilerstage “1” and “1” terminals). This configuration allows for up to 12 stages ofboiler control.

b. For systems with mmoorree tthhaann oonnee ppuummpp, set “nP” to the actual number of pumpsand wire pump #1 using the boiler stage terminals “12” and “12”, wire pump#2 using the boiler stage teminals “11” and “11”, etc.

20. LLeeaadd ppuummpp ((““LLPP”” ppaarraammeetteerr)): The desired pump number to be turned on first,when heat is required. This parameter can be used to make any of the pumpsin the system, lead pump.

TTrroouubbllee SShhoooottiinngg GGuuiiddee::

1. TThhee ddiissppllaayy iiss nnoott lliitt::a. Check power - if 24Vac does not appear across the two terminals marked

“Power In 24Vac”, the control will not operate.b. If power is present, however, the control still does not operate then the

controller requires service.

2. EEiitthheerr tteemmppeerraattuurree sseennssoorr rreeaaddss aa vveerryy llooww tteemmppeerraattuurree ((--3333 ttoo --3355��FF))::a. The sensor is indicating an open circuit. Check for a break in the wire, OR,

reverse the polarity of the sensors wires (swap the black & red wires).b. Try removing the sensor & installing it directly on the S12 terminals:

i. If the sensor reads the temperature of the room then the problem is with thewiring of the sensor run.

ii. If the sensor does not read the temperature of the room then the problem isthe sensor itself - replace sensor.


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TTrroouubbllee SShhoooottiinngg GGuuiiddee:: (cont’d)

3. EEiitthheerr tteemmppeerraattuurree sseennssoorr rreeaaddss aa vveerryy hhiigghh tteemmppeerraattuurree ((221188--222200��FF))::a. The sensor is indicating an short circuit. Check for a short in the wire or sensor.b. Try removing the sensor & installing it directly on the S12 terminals:

i. If the sensor reads the temperature of the room then the problem is with thewiring of the sensor run.

ii. If the sensor does not read the temperature of the room then the problem isthe sensor itself - replace sensor.

4. NNoottee tthhaatt tthhee tteemmppeerraattuurree sseennssoorrss aarree nnoott rreessiissttiivvee eelleemmeennttss bbuutt aarree iinn ffaacctt aarree 22wwiirree ccuurrrreenntt ssoouurrcceess.. TThhee ccuurrrreenntt iinn tthhee sseennssoorr cciirrccuuiitt vvaarriieess wwiitthh tteemmppeerraattuurree aattaa rraattee ooff 11��AA // ��KK.. AA ddiirreecctt ccuurrrreenntt mmeeaassuurreemmeenntt ccaannnnoott bbee mmaaddee dduuee ttoo tthheetteemmppeerraattuurree mmuullttiipplleexxiinngg nnaattuurree ooff tthhee sseennssiinngg cciirrccuuiitt.. IIff aa mmeeaassuurreemmeenntt iissaatttteemmpptteedd,, aa llooww rreeaaddiinngg wwiillll bbee oobbsseerrvveedd..

5. TThhee wwaatteerr tteemmppeerraattuurree ddiissppllaayy sshhoowwss 6600 yyeett tthhee aaccttuuaall wwaatteerr tteemmppeerraattuurree ffeeeellssmmuucchh hhootttteerr tthhaann 6600��FF::a. Check the temperature display units parameter. It is set to �C. Note that the

temperature display units are NOT displayed with the temperature sensorsreadings. For this reason, the user must know in which scale (�F or �C) the S12is set.

6. TThhee SS1122 ssttaaggee iiss lliitt yyeett tthhee bbooiilleerr iiss nnoott ffiirriinngg::a. First check the S12 relay. Remove the boiler wiring from both relay terminals

and check for continuity:i. When the stage is on, there should be a short circuit across the relay

terminals.ii. When the stage is off, there should be an open circuit across the relay

terminals.iii. If either of the above is not found, the control requires service.

b. When the S12 relay checks out correctly then verify the boiler operation. Theboiler is either turned off or is off on a safety device (high limit, operatingaquastat, flow switch, low water cutoff, low or high gas pressure, flame failure,low air flow, etc.). Refer to the boiler manufacturer literature on troubleshooting the boiler.


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Documents

S12 SEQUENCER™ - RBITable 4: Parameter Listing for staging applications. 1300 Midway Blvd., Mississauga, Ontario L5T 2G8 Tel.(905) 670-5888 Fax (905) 670-5782 260 North Elm Street,