PEX-AL-PEX Installation Manual

7/28/2019 PEX-AL-PEX Installation Manual

1/20

INSTALLATION MANUAL

Heating PEXandHeating PEX-AL-PEX


2/20

2


3/20

3

General Handling & Storage1. I Heating PEX or Heating PEX-AL-PEX connections must be made in

temperatures lower than 30.0F (1.1C), caution must be taken to allowthe tubing to orm a proper seal against the barb. Apply the connectionslowly to ensure the tubing material conorms to the barb.

2. Do not allow the luid temperature to exceed:

200.0F (93.3C) at 80 psi (5.5 bar) or Heating PEX. 200.0F (93.3C) at 100 psi (6.9 bar) or Heating PEX-AL-PEX.

3. Do not allow the tubing to be exposed to sunlight, or direct UVexposure or more than 30 days maximum. I stored outside,tubing must remain covered by a UV resistant material.

4. Do not allow the tubing to come in contact with any o the ollowing:

Petroleum based products Pipesealants. Firewallsealants,exceptthoseratedforusewithHeating

PEX or Heating PEX-AL-PEX. Kerosene. Gasoline. Fueloils. Cuttingoils. Asphalt.

Contaminated soils or building materials.

5. Do not use i the tubing has visible gouges, cuts, cracks, abrasions,signs o physical damage, or other deects.

6. Do not use in swimming pools or other systems that use high levels ochlorine.

7. Use bend supports when necessary (Heating PEX only).

8. Do not kink. I kinking occurs, use a repair coupling.

9. Do not expose tubing to rough terrain that may cause punctures, cuts,or other damage.

10. Do not use tubing to transer natural gas or any otherunapproved substance.

Contents

GeneralHandling&Storage 3

GeneralInstallationCautions 3

StandardsandListings 4

Slab-on-gradeApplications 5

SitePreparation 5

Insulation Requirements 5

Type o Insulation 5

Post Concrete Pour 5

ControlJointsandSawCuts 5

TubeSpacing 6

Fasteners 6

SlabProleandGeneralDetails 6

InstallationSteps 6

ThinSlaboverFrameFloorApplications 10

TubeSpacing 10

Fasteners 10

ThinSlabProle 10

InstallationSteps 10


ThinSlabwithSleepers 13

ThinSlabLayoutExample 13

Under Floor Applications 14

TubeSpacing 14

Method o Installation 14

BendSupports 14

Pulling Tubing 14

InstallationSteps 14


Under Floor Layout Example 16

Warranty 17

! WARNINGYou are required to thoroughly read all installation instructionsand product saety inormation beore beginning the installationo this product. FAILURE TO COMPLY WITH PROPERINSTALLATION INSTRUCTIONS COULD RESULT IN PROPERTYDAMAGE and/or PERSONAL INJURY.Local building or plumbing codes may require modifcations tothe inormation provided. You are required to consult the localbuilding and plumbing codes prior to installation. I thisinormation is not consistent with local building or plumbingcodes, the local codes should be ollowed.Watts is not responsible or damages resulting rom improperinstallation and/or maintenance.Contact Watts at 855.699.2887 with any questions concerningthe installation, operation, or maintenance o Watts Heating PEXor Heating PEX-AL-PEX.

! CAUTION

1. Do not install within 6 (152.4 mm) horizontally or 12 (304.8 mm)vertically to a heat source such as: recessed light ixtures combustible lue vents general heating appliances

2. Do not install directly to a heat source. A metallic adapter, minimum18 (457.2 mm) in length, must be used between the heat source

and tubing.3. Do not support ixtures directly rom the tubing, such as hose bibs or

shut-o valves.

4. Protect the tubing via sleeves where it transitions through aconcrete slab, concrete wall, or other raming material.

5. Not to be used with Insulated Barrier Heating PEX products.

NOT FOR

PO

TA E USE

Note: Heating PEX and Heating PEX-AL-PEX arenot approved or intended or use in potablewater applications.

Note: Local building or plumbing codes may

require modiications to the inormationprovided. You are required to consult the

local building and plumbing codes prior

to installation. I this inormation is not

consistent with local building or plumbing

codes, the local codes should be ollowed.


4/20

4

Standards and Listings

Heating PEX:

HeatingPEXismanufacturedtoASTMInternational(ASTMF876andF877)andtoSDR9dimensions.Thesestandardsinclude

requirements and testing methods or materials, workmanship, dimensions, environmental stress cracking, sustained hydro-

static pressure strength, bend strength, and degree o cross-linking. Heating PEX meets or

exceeds these standards.

HeatingPEXistestedandlistedbytheNSFInternationaltoNSF-14(rfh).

HeatingPEXistestedandlistedbyIntertektoASTME84(StandardTestMethodforSurfaceBurningCharacteristicsofBuilding

Materials) and meet the requirements o NFPA 90A.

Heating PEX is tested and listed to UL 263 (Fire Tests o Building Construction and Materials) by Intertek.

HeatingPEXislistedbytheInternationalCodeCouncilEvaluationService(ICC)toReport#ESR-1155,andPMG-1008which

give compliance to IPC/IMC, and UPC/UMC.

HeatingPEXiscertiedtoCSAStandardB137.5.

Expansion Rate: 1.1"/100'/10F.

Allow 1/8" slack or every oot o installed tubing.

The bend radius for Heating PEX may require somebends to be light bulb in shape. This method

allows for tighter on center spacing without

compromising the tubing.

Description ID (OD)

Minimum

Bend Radius

Fluid Capacity

gal/100'

Min. Support

Vertical

Distance

Min. Support

Horizontal

Distance

1/2" Heating PEX 0.485" (5/8") 5" 0.92 48" 32"

3/4" Heating PEX 0.681" (7/8") 7" 1.84 60" 32"

1" Heating PEX 0.875" (1-1/8") 9" 3.04 60" 32"

Temperature Pressure

73.4F (23C) 160 psi (1.10 MPa)

180F ( 82.2C) 100 psi (0.69 MPa)

200F (93.3C) 80 psi (0.55 MPa)

Heating PEX-AL-PEX:

ManufacturedtoASTMF1281

TestedandlistedbytheNSFInternational(NSF-14rfh).

CarriestheUPCcerticationmark,asapprovedbytheInternationalAssociationofPlumbingandMechanicalOfcials(IAPMO).

Expansion Rate: 0.156/100/10F.

Note: No special considerations required to account for thermal expansion.

The bend radius for Heating PEX-AL-PEX is slightly

tighter than Heating PEX but may still require some

bends to be light bulb in shape. It is important,

however, to ensure the minimum bend radius is not

exceeded, as this will cause the tubing to kink. This

method allows for tighter on center spacing without

compromising the tubing.

Description ID (OD)

Minimum

Bend Radius

Fluid Capacity

gal/100'

Min. Support

Vertical

Distance

Min. Support

Horizontal

Distance

1/2" Heating PEX-AL-PEX 0.500" (0.630") 3.2" 0.91 48" 32"

3/4" Heating PEX-AL-PEX 0.806" (0.984") 5.5" 2.53 60" 32"1" Heating PEX-AL-PEX 1.032" (1.260") 6.5" 3.95 60" 32"

Temperature Pressure

73.4F (23C) 200 psi (1.38 MPa)

180F ( 82.2C) 125 psi (0.86 MPa)

200F (93.3C) 100 psi (0.69 MPa)

R3"R4" R5"

8"6" 10"

R4" R4" R5"

8"6" 10"


5/20

5

Slab-on-grade Applications

A common application consisting o any material or mass that

encapsulates the radiant tubing, such as concrete, sand, or soil.

Can be on or below grade.

Site Preparation

A radiant slab should always:

Be placed on well drained base rock material.

Be placed above an ample amount o crushed rock or gravel.

A radiant slab should never: Be placed directly on top o clay or organic subsoil.

Be placed directly on top o solid bedrock.

Insulation Requirements

Two main areas to insulate:

Vertically around the perimeter o the slab (required).

Horizontally underneath the slab.

Bothaidintheslabsresponseandefficiency.Ofthetwo,verticaledge

insulation is the most important or preventing heat loss directly to the

outside environment. Horizontal insulation helps decrease the slabs

required start up time by isolating the slab rom the ground below.

Type o Insulation

Recommended insulation:

Extruded polystyrene insulation board or equivalent.

Not recommended:

Beaded insulation boards.

Foil-aced batt or board insulation.

Bubble-type insulation.

A 1" (25.4 mm) insulation board (R-5 or better) is recommended.

Thicker board may be used in cold, aggressive climates. Always check

with an architect or structural engineer to ensure the appropriate

insulation is used.

Watts does not recommend bubble-type insulation under a slab

application. Most insulations o this type do not oer proper structuralsupport. Consult a structural engineer beore using this or

similar product.

Post Concrete Pour

Ater the slab has been poured, interior walls and other support

structures still have to be installed, typically secured directly to the slab.

Take some preliminary precautions to protect the tubing

during construction. Avoid wall locations, place tubing deeper in the

areas to be below any anchor that will penetrate the slab.

Control Joints and Saw Cuts

Concrete slabs will expand and contract due to thermal changes. To

prevent damage to the slab, expansion joints are used to control

expansion and contraction due to thermal changes. In some cases,saw cuts are used to control where cracking occurs. Make sure the

tubing is protected according to the requirements o the control joint.

Slab-On-Grade Cross Section

Slab

Rewireor Rebar

Heating PEX or

HeatingPEX-AL-PEX

Base Rock

3

Slab Insulation Detail

Minimum 1" (25.4 mm)Extruded Polystyrene Insulation

Slab:Minimum2"(50.8mm)covering above tubing

Control Joint Options

Heating PEX

HeatingPEX-AL-PEX

SubGrade

Slab

12" min.(304.8 mm)

Rewireor Rebar

ProtectiveSleeve Joint

Pass Through

Pass Under

Heating PEX

HeatingPEX-AL-PEX

Slab

Rewire

or Rebar

Joint

SubGradeDo not exceedminimum bendradius o tubing

3" min


6/20

6

12(304.8 mm)

9(228.6 mm)

6(152.4 mm)

Tube Spacing

Residential slabs will use 6" (152.4 mm), 9" (228.6 mm), or 12"

(304.8 mm) tube spacing with some perimeter banding. Banding is

any area where the tubing is installed with a tighter on center spacing.

Usually seen along exterior walls with higher than normal heat loss.

Spacingwiderthan12"(304.8 mm) may produce unacceptable foor

temperature variations (striping). Tube spacing wider than 12" on

center is not recommended.

FastenersTubing can be attached to either the rewire, rebar or below slab

insulation. The ollowing can be used, depending on

installation requirements:

Nylon CableTiesused to secure tubing to either rewire or rebar

12"-18" (304.8 mm - 425.2 mm) on center.

FoamBoardStaplescanbeusedtosecuretubingdirectlytothe

horizontal board insulation below the slab.

Slab Profle and General Details

InSlab-on-Gradeapplications,aminimumof2"-3"(50.8mm-76.2

mm) o concrete covering must be maintained above the tubing. More

coverage may be necessary depending on the structural requirements

o the slab.

Installation Steps

Maniold locations, inal concrete

thickness and zoning details can

aect how a concrete application

is installed. The ollowing

guidelines cover the most

common installation conditions.

I a given situation is not covered

here, or i unexpected

circumstances arise, please

contact Watts or aheating proessional.

1. Pre-Pour Conditions

Veriy all subgrade conditions

are properly prepared.

Rewire or rebar are in place

and installed according to

design conditions.

With orange spray paint, locate all interior walls and other obstacles

to be avoided, such as toilet areas, sewer drains, and any structural

supports that may penetrate the slab.

2. Install ManioldsLocate where the maniolds are to be installed.

Drive two pieces o rebar vertically into the ground. They may be

removed ater the slab is poured and made ready or raming.

Securethemanifoldswiththeuseofcabletiesorelectricaltape.

Keepmanifoldshighenoughtoallowforthethicknessofthe

concrete, the interior wall base plate and other structural items

which may be installed ater the pour.

Tube Spacing

Insulation Layer and/orVapor Barrier

CompactedSubgrade

Typical Rewire Mesh

Slab Subgrade Detail

Manifold Pair

TemporaryRebar

Supports

Slab - Maniold Installation Detail


7/20

7

3. Determine Zone Boundaries

Beore tubing is installed, visually inspect the area to determine the

zone boundaries. This helps determine where the irst circuit is to be

placed, while identiying any obstacles.

4. Confrm Tubing Requirements

Measure the distance rom the

maniolds to the arthest point in

the zone via right angles.

Make sure the minimum circuitlength is at least twice this distance.

I not, the tubing will not be long

enough to reach the arthest point

o the zone and return.

5. Install Tubing

Pull one end o tubing o the

unwinderandattachittotherst

barb o one o the maniolds.

Install using a single serpentine

pattern, keeping the tubing 6"-8"

(152.4 mm - 203.2 mm)

rom the edge o the slab.

Pay attention to the ootage marking

on the tubing and cut at the

correct length.

At expansion/control joints, the

tubing may be passed under the

area or must be sleeved with

Armafex or PVC to pass through

expansion/control joints (see

Expansion Joints or details).

Use 1/2" (12.7 mm) tubing or the

radiant foor.

Use 3/4" (19.1 mm) or

1" (25.4 mm) Heating PEX or

Heating PEX-AL-PEX or supply

and return lines to the zone.

Supply Manifold

Return Manifold

Maniold

Location

ManioldLocation


8/20

8

6. Secure the Tubing

SecureallbendsandcornerstopreventHeatingPEXfromcurling,

creating an unwanted high point in the circuit.

Leave 5' (1.52 m) slack on each circuit to allow adjustment o

the maniold position rom its temporary location.

Trim all tails o the cable ties to prevent any unwanted

surace protrusions.

Keepallcircuitswithin10%ofthesamelength.

8. Inspection

Visually inspect each circuit o tubing or possible damage caused

during installation. I damage is ound, repair it using an approved

Watts repair kit. Wrap the repair with electrical tape (do not use duct

tape) to protect the connection rom the concrete.

9. Pressure Test

Pressure test the system with 50 - 100 psi (3.4 - 6.9 bar) water or air or

24 hours. Do not use water i exterior temperatures are near or below

reezing (32.0F (0.0C)) conditions.

Attach the pressure test kit to the maniold pair making certain

the rubber o-rings are properly seated beore threading the

unions together. UsingtheSchraedervalveforairorthewaterllvalvesforliquid,

llthesystem(airorwater,butnotboth).

Closethevalveandll.Pressuretestthesystemwith50-100psi

(3.4 - 6.9 bar) water or air or 24 hours.

Note: I the exterior temperatures are near or below

reezing (32.0F (0.0C )) use air to pressure test. I a

luid must be used, use a 50-50 water/glycol

solution. Failure to use glycol may result in rozen

circuits. The cool night air will usually cause less

than a 10 psi drop in pressure as the water or air

contracts rom the cold.

Do not test over 100 psi, (6.9 bar) as this will damagethe gauge on the test kit.

Some minor pressure changes will occur due to

the increased internal temperatures o the concrete

as it begins the curing process. Fluctuations in air

temperature may also cause a slight change in the

test pressure. In most cases, a 10-15 psi (0.7 - 1.0

bar) drop in pressure over a twenty our hour period

is not uncommon.

10. The Concrete Pour

To help detect possible damage caused during the concrete pour, keep

the system under pressure. I damage is apparent, locate the area inquestion and repair.

Minor pressure changes will occur during the concrete curing process.

Fluctuations in air temperature may cause slight changes in the test

pressure. In most cases, a 10-15 psi (0.7 - 1.0 bar) drop in pressure

over a 24 hour period is not uncommon.

Heatedwatershouldnotbecirculatedthroughthenishedpourfora

minimum o 28 days, or until the concrete slab is ully cured.

Maniold Pressure Test Kit and Connection Detail

Slab Loop Installation Detail

Rewireor Rebar Heating PEX or

HeatingPEX-AL-PEX

Cable Tie

Barb

Compression Ring

Compression Nut

Heating PEX or

Heating PEX-AL-PEX

Balance Valve

SupplyManifold

Mounting Bracket

AirTestGauge

SchraderValve

ReturnManiold

Vent/Purge

Drain

Drain

Slab-on-grade Cutaway

Rewireor Rebar Heating PEX or

Heating PEX-AL-PEX

Slab

Subgrade


9/20

9

Slab Layout Examples

ManioldLocation

ManioldLocation


10/20

10

Thin Slab over Frame Floor Applications

Most thin slab applications are installed during the initial construction

o a building, due to the increased structural requirements to carry the

added weight.

Lightweight concrete products will increase the foor height by a

minimum o 1.5" (38.1 mm) and the foor load anywhere between

12 to 18 lbs/sq.t (5.44 k to 8.16 k).

Theincreaseinloadusuallymeansamodicationtothejoistsystem

and/or other supports.

Veriy a foors ability to withstand these loads prior to installing a

lightweight concrete product.

Tube Spacing

Residential thin slabs will use 6" (152.4 mm), 9" (228.6 mm), or

12" (304.8 mm) tube spacing with some perimeter banding. Banding

is any area where the tubing is installed with a tighter on center

spacing. Usually seen along exterior walls with higher than normal

heat loss.

Tubing is generally attached directly to the subfoor with the use o

staples and/or NailTites.

Fasteners

The sub-material the thin slab is installed over will determine how

the tubing can be attached. The most common sub-material is a

wooden subfoor.

Staplesspacedevery18"-24"(457.2mm-609.6mm)oncenter.Use a staple gun set to 100 psi.

Thin slab Profle

It is important to maintain at least 3/4" (19.1 mm) o thin slab material

above the tubing.

More coverage may be necessary depending on the structural

requirements o the slab/structure.

Installation Steps

Manifoldlocations,nalconcretethickness,andzoningdetailsarejust

a ew items that can aect how a thin slab application is installed. The

ollowing guidelines cover the most common installation conditions. I

a given situation is not covered here, or i unexpected circumstancesarise, please contact Watts or a heating proessional.

1. Install Maniolds

Locate where the maniolds are to be placed.

With the use o Watts maniold brackets or maniold mounting

enclosure, secure the maniolds to the wall.

Allowances may need to be made to allow the tubing to transer

through the wall base plate and into the thin slab.

Follow local code guidelines when penetrating raming base plates.

12" max(304.8 mm)

Thin Slab Over Framed Cross Section

Thin Slab Tube Spacing

Thin Slab - Maniold Installation Detail

ThinSlab

SubFloor

Heating PEX orHeatingPEX-AL-PEX

Insulation

Floor Covering

Mimimum 1-1/2"

(38.1mm)ThinSlab

Insulation

Maniold

ThinSlab

Heating PEX oHeatingPEX-AL-PEX

Note: Local building or plumbing codes may require

modiications to the inormation provided. You

are required to consult the local building and

plumbing codes prior to installation. I this

inormation is not consistent with local building

or plumbing codes, the local codes should

be ollowed.


11/20

11


Beore tubing is installed, visually inspect the area to determine the

zoneboundaries.Thishelpsdeterminewheretherstcircuitistobe



Measure the distance rom the

maniolds to the arthest point in

the zone.

Make sure the minimum circuit lengthis at least twice this distance. I not, the

tubing will not be long enough to reach

the arthest point and still have enough

length to return to the maniold.

4. Install Tubing

Pull one end o tubing o the unwinder

andattachittotherstbarbonthe

supply maniold.

Lay the tubing along the perimeter

walls to the arthest point in the zone,

keeping the tubing 6"-8" (152.4 mm -

203.2 mm) rom the edge o the slab.This will help protect the tubing rom

possible penetrations later on when the

nalfloorcoveringisinstalled.

Pay attention to the ootage marking on

the tubing and cut at the correct length.

Bend supports may be used to secure

the tubing as it transitions rom the thin

slab to the wall.

In most thin slab applications, built-ins

such as cabinets, showers, and walls

are already in place beore the thin slab

is poured. Tubing is generally run around

these built-ins.

Most structural code requirements

restrict the amount o material that

can be removed rom a wall member.

It is advised to run the tubing through

doorways, or other openings,

whenever possible.

Supply Manifold

Return Manifold

Thin Slab20 8 (6 3 m)

16 8(5 1 m)

Supply Manifold

Return Manifold

Thin Slab

ManioldLocation


12/20

12

5. Securing Tubing

When installing a thin slab over a subfoor, standard staples are used.

Make sure the staple gun is set to 100 psi (6.9 bar) and does not

comeincontactwiththetubing.Securethetubingtothefloorevery

18"-24" (457.2 mm - 609.6 mm).

Trytokeepallcircuitswithin10%ofthesamelength.

6. Inspection

Visually inspect each circuit o tubing or possible damage caused

during installation. I damage is ound, repair it using an approvedWatts repair kit. Wrap the repair with electrical tape (do not use duct

tape) to protect the connection rom the concrete.

7. Pressure Test

Pressure test the system with 50-100 psi (3.4 - 6.9 bar) water or air or





unions together.

UsingtheSchraedervalveforairorthewaterllvalvesforliquid,llthesystem(airorwater,butnotboth).

Closethevalveandll.Pressuretestthesystemwith50 - 100 psi



reezing (32.0F (0.0C)) use air to pressure test. I

a luid must be used, use a 50-50 water/glycol





Do not test over 100 psi, (6.9 bat) as this will damage

the gauge on the test kit.







is not uncommon.

8. The Thin Slab Pour

To help detect possible damage caused during the concrete pour, keep

the system under pressure. I damage is apparent, locate the area in

question and repair. Minor pressure changes will occur during the concrete curing process.

Fluctuations in air temperature may cause slight changes in the test

pressure. In most cases, a 10-15 lb (0.7 - 1.0 bar) drop in pressure

over a twenty our hour period is not uncommon.

Heatedwatershouldnotbecirculatedthroughthenishedpourfora

minimum o 28 days, or until the concrete slab is ully cured.

Thin Slab Loop Installation Detail

ThinSlab

Heating PEX orHeating PEX-AL-PEX

Staple18" to 24"


Barb

Compression Ring

Compression Nut

Heating PEX or

Heating PEX-AL-PEX

Balance Valve

SupplyManifold

Mounting BracketAirTestGauge

SchraderValve

ReturnManiold

Vent/Purge

Drain

Drain

Thin Slab Cutaway

ThinSlab

Heating PEX or

Heating PEX-AL-PEX

Finished Floor

Subfloor


13/20

13


A standard paper aced insulation can be used in the joist cavity.

Install the insulation tight against the subfoor to minimize any

convective losses that may be generated.

The insulation should be a minimum o 3-1/2" (88.9 mm), or R-13,

berglassbattwhentheradiantfloorisinstalledoveraheatedspace,

such as a basement. 5-1/2"(139.7 mm), or R-19, batt (or thicker,

depending on the climate) should be used when the area below the

radiant foor is unheated or exposed to the elements.

Thin Slab with Sleepers

Wooden sleepers are sometimes installed within a thin slab

application to allow or points o attachment or hardwood or other

foor coverings.

Please note:In a thin slab application,typically the tubing will berun through doorways andother openings rather than

directly through walls.

Thin Slab Insulation Detail

Thin Slab Layout Example

12" max(304.8 mm) ThinSlab

Insulation

SHOWERSPA TUB

LINEN

STORAGE

WALK-IN

CLOSET

GASFIREP

LACE

MASTER

BATH

MASTER SUITE

Thin Slab with Sleepers Insulation Detail

8"(203.2 mm) ThinSlab

Insulation

Heating PEX or

Heating PEX-AL-PEX

ManioldLocation

Heating PEX or

Heating PEX-AL-PEX

WoodenSleeper


14/20

14

Under Floor Applications

Minimizes the structural load requirements oten associated with lightweight concrete (thin slab) construction.

Requires no foor height additions, or removal o existing foor

coverings to install. Ideal or renovation projects.

Make sure the tubing is installed in accordance with the design

parameters. I not, the system may not unction as desired.

Requires the use o either a 1" (25.4 mm) or a 1-3/4" (44.4 mm)

auger drill to install between joist bays, depending on how tubing

is installed.

Tube Spacing

Tubing is installed 8" (203.2 mm) on center, to the underside o the

subfoor with the use o heat transer plates.

Method o InstallationExtruded aluminum heat transer plates are the primary astening

method o installing an under loor system. Watts oers heat transer

plates designed to be used with 1/2" (12.7 mm) Heating PEX or

Heating PEX-AL-PEX and are available in 4' (1.2 m) lengths. The plates

are installed 8" (203.2 mm) on center with a 2"-4" (50.8 mm - 101.6

mm) gap between plates.

Bend Supports

Bend supports may be required i it is necessary to maintain a

certainbendradius,orifconnectingtoattingimmediatelyafter

a bend.

Pulling Tubing

Install the heat transer plates beore beginning to pull the tubing.Make sure the end o the plate is de-burred ater cutting the plate

totbeforeinstallingthetubing.

Measure the distance rom the maniold to the arthest point moving

in right angles to ensure proper circuit length is being used. This

distance should be less than the circuit length or the zone.

Installation Steps

1. Install maniolds.

Locate where the maniolds are to be placed.

With the use o Watts maniold brackets or maniold mounting

enclosure, secure the maniolds to the wall.


Beore tubing is installed, visually inspect the area to determine thezoneboundaries.Thishelpsdeterminewheretherstcircuitistobe



Measure the distance rom the maniolds to the arthest point in the

zone. Make sure the minimum circuit length is at least twice this dis-

tance. I not, the tubing will not be long enough to reach the arthest

point o the zone and return (see slab section or illustration)

Return Manfold

Supply Manifold

Under Floor Application Cross Section

Confrm Tubing Requirements

Under Floor Tube Spacing

8"

2 (50.8 mm) air gap

(203.2 mm)

Heating PEX orHeatingPEX-AL-PEX Heat Transer Plate

Foil Faced Insulation

anser

Heating PEX orHeatingPEX-AL-PEX


SubFloor

Note: Local building or plumbing codes may require

modiications to the inormation provided. You

are required to consult the local building and

plumbing codes prior to installation. I this

inormation is not consistent with local building

or plumbing codes, the local codes should

be ollowed.


15/20

15

4. Drill joists (i necessary)

Drill in accordance to structural requirements. To help keep the holes

inline,itmaybehelpfultorstmarkthejoistswithachalkline.

I the supply and return sections o the circuit are to be installed

through a common joist transition point, a 1-3/4" (44.4 mm) hole is

required (option 1). I the supply and return sections are to be run in

dedicated transition points, 1" (25.4 mm) holes can be used (option 2).

I using TJI joists, it may be possible to use the pre-abricated

knock-outs instead o having to drill transition points. Make sure

the knock-outs are large enough or the tubing beore proceeding.

Frame Floor Section - Maniold Installation

Under Floor Joist Penetration Detail

1-3/4"(44.4 mm)

Option 1

Option 2

Under Floor - Maniold Installation Detail

Whencrossingajoistataperpendicularangle,itisrecommendedtofollowBOCA2305.3.2 guidelines or allowable joist penetrations.

Penetrations can not be closer

than 2" (50.8 mm) to the top

or bottom o the joist.

2" (50.8 mm) minimum

spacing between penetrations.

center linepenetration zone joist heightmax. bore size: 1/3 joist height

Stayamin.of8"

(203.2 mm) rom

end o joist.

BOCA Joist Penetration Guideline


16/20

16

5. Install Tubing

Pull one end o the tubing rom the unwinder and eed through the

rstjoist.

Create a large loop with the tube and eed the ree end through the

adjacent joist.

Make a small loop in each bay as you work towards the bay arthest

fromthemanifold.Pullenoughtubingtollthelastbay.Ifadditional

tubing is required, pull it rom the loop in the previous bay. I too much

was pulled, push it back into the previous bay. Care should be taken

not to kink the tubing.

Run the end o the tubing back to the maniold. Drill a return hole 8"

(203.2mm)awayfromtherst.

Place the tubing into the asteners. Begin by attaching the run o

tubing that is part o the return line going back to the maniold. This

sideoftheloopisxed.Theothersideisfreetofeedfromthe

unwinder and previous bays in case extra tubing is required.

Always remember to place the tubing so bends have the largest

radius possible.

Inspection

Ater all the circuits are installed, take a ew minutes to walk each

circuit and visually inspect the tubing or possible damage caused

during installation. I damage is ound, repair it using an approved

Watts repair kit.

Pressure Test

Pressure test the system with 50-100 psi (3.4 - 6.9 bar) water or air or





unions together.

UsingtheSchraedervalveforairorthewaterllvalvesforliquid,

llthesystem(airorwater,butnotboth).

Closethevalveandll.Pressuretestthesystemwith50-100psi



reezing (32.0F (0.0C)) use air to pressure test.

I a luid must be used, use a 50-50 water/glycol





Do not test over 100 psi (6.9 bar), as this will damage

the gauge on the test kit.







is not uncommon.


Barb

Compression Ring

Compression Nut

Heating PEX or

Heating PEX-AL-PEX

Balance Valve

SupplyManifold

Mounting Bracket

AirTestGauge

SchraderValve

ReturnManiold

Vent/Purge

Drain

Drain

1. Pull a loop o tubing in the

rstjoistbay.

2. Continue to the next bay,

pulling rom the previous

loop. Tubing will need to be

pulled rom the unwinder

as well to keep enough o

aloopintherstbay.

3. Repeat or each

subsequent bay

4. Pull enough tubing to complete the last

bay using the loop in the previous bay as a

buer or extra tubing.


17/20

17

2 (50.8 mm)

Return Manifold

Supply Manifold

Under Floor Layout Example

Heating PEX or

Heating PEX-AL-PEXHeat Transer Plate



It is important to have a tight seal between the horizontal insulation

and the joist itsel. The tighter the joist cavity, the better the system

will perorm.

Foil insulation will ensure most o the heat and energy coming rom

the tubing is refected upward towards the subfoor where it is evenly

distributed..

A 2-4" (50.8 -101.6 mm) air gap is necessary between the tubing and

insulation. This air gap helps increase the eective R-value o the in-

sulation while optimizing the ability o the oil to refect energy.

An R-value o at least 4 times higher than the foor is desire. For most

interior conditions, an R-13, or a 3-1/2" (88.9 mm) batt should be used.

When installing over an unheated area, exposed area or crawlspace, a

minimum R-19 or 6" (152.4 mm) batt should be used.


18/20

18

HEATING PEX and Heating PEX-AL-PEXHEATING, COOLING, and

SNOW MELTING LIMITED WARRANTY

From Watts

1. Watts warrants its Heating PEX cross-linked polyethylene tubing, Heating PEX-AL-PEX cross-linked polyethylene/

aluminum/cross linked polyethylene tubing, fittings, and factory manufactured manifolds to be free of defects in materialand workmanship when used in hydronic heating, cooling, and snow melting systems. This limited warranty for tubing

is valid for a period of twenty-five years from the date of manufacture. This limited warranty for Watts manufactured

manifolds and fittings expires two years from the date of manufacture. All other Heating PEX and Heating PEX-AL-PEX

accessories are warranted for one year after date of installation.

2. Watts obligation will be to repair or replace, at its discretion, any material proven to be defective when such material is cov-

ered under the following limited warranty.

3. In order to qualify for a labor allowance to repair or replace defective materials, you must contact Watts in advance

and receive a written authorization for this allowance. Labor and freight expenses not authorized in writing in

advance by Watts will not be compensated.

4. In the event of a system malfunction or leak caused by defective materials (and not by incorrect installation procedures

or damage from handling procedures/jobsite conditions) repair materials and a reasonable labor allowance will be allowed.

In the event of a leak occurring in a factory manifold, you may contact Watts for a free replacement manifold or any needed

parts (freight prepaid). In the case of field-assembled manifolds, Watts warrants the quality and serviceability of theindividual components sold by Watts that the contractor incorporates in that manifold, but Watts cannot warrant the

complete manifold assembly or any field-assembled connections. That is the responsibility of the installing contractor.

5. To qualify for the above warranty you must do the following:

a. Use good construction techniques to install our materials, as specified in our current design and installation guidelines

and technical notes. This must include field pressure testing our materials before they are covered by concrete or

otherwise made inaccessible.

b. Install our materials according to all specific instructions furnished for your installation.

c. Install Heating PEX or Heating PEX-AL-PEX in a system that will not operate at temperatures exceeding ratings as

marked on the tubing.

d. Product must be installed in compliance with all applicable plumbing, heating, cooling, and/or mechanical codes.

6. Evidence of tampering, mishandling, neglect, accidental damage, freeze damage, or unauthorized repairs that cause damage

to Watts products will void any warranty coverage for these particular damages, although it will not void warranty coverage

for unrelated items. Field repair joints and tubing-to-manifold connections are specifically excluded from the terms of

this warranty.

7. Watts provides a complete radiant system offering so that it is possible to complete an installation with Watts products.

However, it is possible that other manufacturers tubing and/or fittings may be installed in any given installation. Providing

that the tubing and/or fittings are manufactured to the applicable ASTM standards, and have been certified by a recognized

third-party testing agency, the Watts product in the given installation will continue to be covered under this warranty. In

the event of a system malfunction or leak that has other tubing and/or fitting manufacturers components installed within

the failed system, Watts will be responsible only for Watts products. Products manufactured by another company should be

reported to that manufacturer for their warranty response.

WATTS DISCLAIMS ANY WARRANTY NOT PROVIDED HEREIN, INCLUDING ANY IMPLIED WARRANTY OF

MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. WATTS FURTHER DISCLAIMS ANY RESPONSIBILITY

FOR SPECIAL, INDIRECT, SECONDARY, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING FROM OWNERSHIP OR

USE OF THIS PRODUCT, INCLUDING INCONVENIENCE OR LOSS OF USE OR THE COST OF REPLACING OR REPAIRING

OTHER PROPERTY WHICH IS DAMAGED IF THIS PRODUCT DOES NOT WORK PROPERLY. THERE ARE NO WARRANTIES

WHICH EXTEND BEYOND THE FACE OF THIS DOCUMENT. NO AGENT OR REPRESENTATIVE OF Watts HAS ANY

AUTHORITY TO EXTEND OR MODIFY THIS WARRANTY UNLESS SUCH EXTENSION OR MODIFICATION IS MADE IN

WRITING BY A CORPORATE OFFICER.

8. Some states do not allow the exclusion or limitation of incidental or consequential damages and some states do not allow

limitations on how long implied warranties may last. Therefore, the above limitations or exclusions may not apply to you.

This warranty gives you specific legal rights and you may also have other rights which vary from state to state.

Effective: July 1, 2011

This warranty applies to all products purchased after this date.

Watts Regulator Company 815 Chestnut St. No. Andover, MA 01845

855-699-2887 (USA and Canada) 978-794-1848 (Fax) radiant.watts.com


19/20

19


20/20

815ChestnutSt

No. Andover, MA 01845

ph: 855.699.2887

ax: 978.794.1848

radiant.watts.com

In Canada5435NorthServiceRoad

Burlington,ONL7L-5H7

ph: 888.208.8927

905.332.4090

ax: 888.882.1979

905.332.7068

radiant.watts.com

Materials and Tools Checklist

Measuring Tape

Chalk Line

Electrical Tape

Marker

Electric Drill

1-3/4"(44.5mm)HoleSaw

SafetyGlasses

Tubing Unwinder

Tubing Cutter

BendSupports(forHeatingPEXinstallationonly)

Maniold Box (optional)

Heating PEX or Heating PEX-AL-PEX tubing

WattsCopperCompressionManifoldKit(withcorrectnumberofcircuitconnectionsfortubingtypeinstalled)

Heating PEX-AL-PEX Reamer (i installing Heating PEX-AL-PEX tubing)

Railways (or slab-on-grade installations)

FoamBoardStapler(forinsulatedslab-on-gradeinstallationsonly)

FoamBoardStaples(forinsulatedslab-on-gradeinstallationsonly)

FoamBoardScrewClipTool(forinsulatedslab-on-gradeinstallationsonly)

FoamBoardScrewClips(forinsulatedslab-on-gradeinstallationsonly)

Cable Ties (or slab-on-grade installations)

Heat Transer Plates (or under loor installations only)

Under Floor Clips (or under loor suspended installations only)

WattsPressureTestKit

NOTFOR

PO

TABL E USE

Documents

PEX-AL-PEX Installation Manual