Raypak P-3001, P-3500, P-1468, P-1631, P-962 Installation & Operating Instructions Manual

INSTALLATION & OPERATING

INSTRUCTIONS

®

Raytherm
Commercial
Swimming
Pool
Heater

Models P-926 to P-1826

& P-2100 to P-4001

WARNING: If these instructions are not followed exactly, a fire or explosion may

result causing property damage, personal injury or death.

FOR YOUR SAFETY: Do not store or use gasoline or other flammable vapors and
liquids or other combustible materials in the vicinity of this or any other appliance.
To do so may result in an explosion or fire.

WHAT TO DO IF YOU SMELL GAS:

• Do not try to light any appliance.

• Do not touch any electrical switch; do not use any phone in your building.

• Immediately call your gas supplier from a neighbor’s phone. Follow the gas
supplier’s instructions.

• If you cannot reach your gas supplier, call the fire department.

Installation and service must be performed by a qualified installer, service agency or
the gas supplier.

This manual should be maintained in legible condition and kept adjacent to the heater or in another safe place for
future reference.

CATALOG NO. 6200.51T Effective: 05-15-18 Replaces: 07-01-16 P/N 240251 Rev. 21

WATER CHEMISTRY

(Corrosive water voids all warranties)

For your health and the protection of your pool equipment, it is essential that your
water be chemically balanced. The following levels must be used as a guide for bal­anced water.

Recommended Level(s) Fiberglass Pools Fiberglass Spas

Other Pool & Spa

Types

Water Temp. (Deg. F) 68 to 88 89 to 104 68 to 104

pH 7.3 to 7.4 7.3 to 7.4 7.6 to 7.8

Total Alkalinity (PPM) 120 to 150 120 to 150 80 to 120

Calcium Hardness (PPM) 200 to 300 150 to 200 200 to 400

Salt (PPM) 6000 MAXIMUM 6000 MAXIMUM 6000 MAXIMUM

Free Chlorine (PPM)* 2 to 3 2 to 3 2 to 3

Total Dissolved Solids
(PPM)

3000 MAXIMUM 3000 MAXIMUM 3000 MAXIMUM

* Free Chlorine MUST NOT EXCEED 5 PPM!

• Occasional chemical shock dosing of the pool or spa water should not damage the
heater providing the water is balanced.

• Automatic chemical dosing devices and salt chlorinators are usually more efficient
in heated water, unless controlled, they can lead to excessive chlorine level which
can damage your heater, and which is not covered under warranty.

• Further advice should be obtained from your pool or spa builder, accredited pool
shop, or chemical supplier for the correct levels for your water.

Revision 21 reflects the following changes:

Removed California Proposition 65 on page 4.

2

CONTENTS

WATER CHEMISTRY 2
WARNINGS 4

Pay Attention to These Terms 4

RECEIVING EQUIPMENT 5
GENERAL
SPECIFICATIONS 5
INSTALLATION 5

Code Requirements 5
Base Installation 5
Clearances 6
Combustion Air (Indoor Units Only) 6
Venting Connections 7
Gas Supply Connections 8
Water Connections 10

CONTROLS 10

Flow Switch 10
Water Pressure Switch 11
Automatic Chlorinators and Chemical
Feeders 11
Unitherm Governor Operation 11
Companion Flange Connections
(Models 926-1223) 11
Mounting the Poolstat Control with Front­Mounted Loop Using Mounting Slots 12
Mounting Well into System Return Loop
Pipe - Front-Mounted Loop 14
Piping Configurations for Raytherm
Commercial Pool Heaters (926-1223) 15
Piping Configurations for Raytherm
Commercial Pool Heaters (1287-1826) 16
Piping Configurations for Raytherm
Commercial Pool Heaters (2100-4001) 17
Temperature Controls 18
External Auxiliary Bypass Valve (Where
Required) Models 926-1223 Only 18
Auxiliary Bypass Valve Adjustment 18
Electrical Wiring 19

Wiring Diagram—Models 926–1223
with UG 20
Wiring Diagram—Models 926–1826
with H-Bypass 21
Wiring Diagram—Models 2100–2500 22
Wiring Diagram—Models 3001–4001 23

SERVICING 24

General Location Of Controls 24
Temperature Control 24
Pressure Switch 24
Pressure Switch Adjustment 24
Two-Speed Pumps 25
Pilot Safety 25

START-UP PROCEDURES 25

Before Start-Up 25
Start-Up 25
After Start-Up 26

INSPECTION PROCEDURES 26

Burners 26

CONTROLS 26
SERVICING PROCEDURES 27

Tube Cleaning Procedure (Typical) 27
Heat Exchanger Reassembly 27
Burner Drawer Removal 27
Gas Valve Removal 27
Main Burner and Orifice Removal 28
Pilot Removal and Cleaning 28
Heat Exchanger Removal 28
Combustion Chamber Removal 29
Control Well Replacement 29
Tube Replacement Procedure 29
Procedure For Cleaning Flue Gas
Passageways 29
Unitherm Governor Replacement 30

MAINTENANCE AND CARE 30

Winterizing Your Heater 31

TROUBLESHOOTING 32

3

WARNINGS

Pay Attention to These Terms

DANGER:

WARNING:

CAUTION:

NOTE:

DANGER: Make sure the gas on which the heater

will operate is the same type as that specified on the
heater rating plate.

WARNING: Should overheating occur or the gas
supply valve fail to shut, do not turn off or disconnect
the electrical supply to the heater. Instead, shut off
the gas supply at a location external to the heater.

WARNING: To minimize the possibility of improper
operation, serious personal injury, fire, or damage to
the heater:

• Always keep the area around the heater free of
combustible materials, gasoline, and other flam­mable liquids and vapors.

Indicates the presence of immediate hazards which will cause severe person­al injury, death or substantial property damage if ignored.

Indicates the presence of hazards or unsafe practices which could cause
severe personal injury, death or substantial property damage if ignored.

Indicates the presence of hazards or unsafe practices which could cause
minor personal injury or product or property damage if ignored.

Indicates special instructions on installation, operation, or maintenance which
are important but not related to personal injury hazards.

CAUTION: Operation of this heater in low­temperature systems requires special piping.
Harmful internal condensation will occur if the inlet
water temperature does not exceed 105°F. Warranty
claims will be denied when condensation occurs.

CAUTION: If this heater is to be installed above
radiation level, it must be provided with a low water
cut-off device at the time of heater installation.

CAUTION: If this heater is to be installed in a
negative or positive pressure equipment room, there
are special installation requirements. Consult factory
for details.

• Heater should never be covered or have any
blockage to the flow of fresh air to the heater.

WARNING: Do not use this heater if any part
has been under water. Immediately call a qualified
service technician to inspect the heater and to
replace any part of the control system and any gas
control which has been under water.

WARNING: Risk of electrical shock. More than one
disconnect switch may be required to deenergize the
equipment before servicing.

4

RECEIVING EQUIPMENT

INSTALLATION

On receipt of the equipment, visually check for exter­nal damage to the carton or the shipping crate. If the
carton or shipping crate is damaged, make a note on
the Bill of Lading and report the damage to the Carrier
immediately. Remove the heater from the carton or
shipping crate. Do NOT use the shipping base crate
as an installation base.

On occasion, we ship some items loose. Be sure that
you receive the number of packages indicated on the
Bill of Lading. When ordering parts, you must specify
Model and Serial Number of heater. When ordering
under warranty conditions, you must also specify date
of installation.

Raypak recommends that this manual be reviewed
thoroughly before installing your Raypak Pool Heater.
If there are any questions which this manual does not
answer, please contact the factory or your local
Raypak representative.

Claims for shortages and damages must be filed with
carrier by consignee. Permission to return goods must
be factory authorized and are subject to a stocking
charge.

These instructions are intended for the use of qualified
personnel only, specifically trained and experienced in
the installation of this type of heating equipment and
related system components. Installation and service
personnel may be required by some states to be
licensed. If your state is such, be sure your contractor
bears the appropriate license. Persons not qualified
shall not attempt to fix this equipment nor attempt
repairs according to these instructions.

WARNING: Improper installation, adjustment,
alteration, service or maintenance may damage the
equipment, create a hazard resulting in asphyxiation,
explosion or fire, and will void the warranty.

Code Requirements

The heater should not be located in an area where
possible water leakage will result in damage to the
area adjacent to the appliance or to the structure.
When such locations cannot be avoided, it is recom­mended that a suitable drain pan, adequately drained,
be installed under the appliance. The pan must not
restrict combustion air flow.

Purchased parts are subject to replacement only
under the manufacturer’s warranty. Debits for defec­tive replacement parts will not be accepted and will be
replaced in kind only per our standard warranties.

GENERAL
SPECIFICATIONS

Models 962, 1125, 1223, 1336, 1468, 1631, 1826 &
2100 through 4001 are specifically designed for indoor
installation ONLY. Models 926, 1083, 1178, 1287,
1414, 1571 & 1758 are specifically designed for out­door installation ONLY. All heaters are standard with
electronic ignition for both natural and propane appli­cations. Heaters require 120V power supply. Control
circuits operate at 24V, supplied by an internal 120V
to 24V transformer.

These heaters are design certified and tested under
the requirements of ANSI Z21.56 / CSA 4.7 American
National Standard for Gas-Fired Pool Heaters. Rated
inputs are suitable for up to 2000 feet elevation. For
elevations above 2000 feet, reduce input 4% for each
1000 feet above sea level, as high elevation reduces
combustion performance.

Installation must be in accordance with local codes, or,
in the absence of local codes, with the latest editions
of the National Fuel Gas Code (NFGC), ANSI Z223.1/
NFPA 54, and National Electrical Code (NEC), ANSI/
NFPA 70.

Base Installation

Do NOT use the shipping base crate as an installation
base. Heater must be mounted on a level base, such
as cement slab, cement blocks or other non-com­bustible surface. An optional non-combustible base
is available for Indoor Models 962 through 1826. An
alternative method for providing a base for combus­tible floors as illustrated below. Heaters may not be
installed on carpeting.

5

Fig. 1: Alternate Mounting Base

Clearances

All Heaters

For clearances from combustible surfaces, see
Table A below. A minimal vertical clearance of three
feet between the upper surface of the flue outlet to a
noncombustible material is required.

Indoor Heaters

Heater

Side

Top 24 Top 24

Back 24 Back 24

Right Side 24 Right Side 24

Left Side 24 Left Side 24

Vent* 6

*Vent includes factory supplied drafthood and does not include field
supplied vent systems above the drafthood. On Models 2100-4001
drafthood is built into heater.
For servicing provide a front clearance as shown below:
Model 926/962-758/1826 - 24”
Model 2100-4001 - 48”

Table A: Minimum Clearances from Combustible

For servicing, provide at least 24” in front of the heater
on Models 926-1826 & 48” in front of the heater on
Models 2100-4001 for burner tray removal, and at
least 18” on the right side of the heater to inspect and
delime the heat exchanger.

Clearance

(Inches)

Construction

Outdoor Heaters (926–

1758)

Heater

Side

Clearance

(Inches)

Outdoor Heaters (Models 926-1758)

Fig. 2: Minimum Distance from Openings

The point from where the flue products exit the heater
must be a minimum of four (4) feet below, four (4) feet
horizontally from or one (1) foot above any door, win­dow or gravity inlet to a building. The top surface of
the heater shall be at least three (3) feet above any
forced air inlet, or intake ducts located within ten (10 )
feet horizontally.

High Wind Conditions
(Outdoor Units Only)

In areas where high winds are frequent, it may be nec­essary to locate the heater a minimum of 3’ from high
vertical walls, or install a wind break so the heater is
not in direct wind current.

Indoor Heaters

The design is certified for indoor installation when
equipped with approved drafthood. Locate the heater
as close as practical to a chimney or gas vent.

These heaters are design-certified for outdoor installa­tion, when equipped with the approved top designated
for outdoor use. Heaters must not be installed under
an overhang of less than three (3) feet from the top of
the heater. Three (3) sides must be open in the area
under the overhang. Roof water drainage must be
diverted away from heaters installed under overhangs
with the use of gutters.

WARNING: The heater shall not be located in an
area where water sprinklers, or other devices, may
cause water to spray through the cabinet louvers
and into the heater. This could cause heavy internal
rusting or damage some electrical components, and
this would void the warranty.

Combustion Air
(Indoor Units Only)

The heater must have both combustion and ventila­tion air. Openings must not be obstructed. Minimum
requirements are from the National Fuel Gas Code

CAUTION: Combustion air must not be
contaminated by corrosive chemical fumes which
can cause unwarrantable damage to the heater.

6

(ANSI Z223.1/NFPA 54).
The “two-opening” method requires:

1. Free combustion air 1 sq. in. per 1000 BTU input
within 12” of the floor.

2. Free ventilation air 1 sq. in. per 1000 BTU input
within 12” of the ceiling level.

NOTE: If the room the heater is installed in is
located against an outside wall and air openings
communicate directly with the outdoors, the openings
may be 1/4 the size specified above (ANSI Z223.1/
NFPA 54, latest edition)

Venting Connections

Drafthood (Indoor) Models 962-1826

Locate and assemble as shown in Fig. 3. Secure with
screws supplied in envelope in carton. Do not modify
the drafthood. The height of the relief openings above

pipe must have a minimum of 1/4 inch per foot rise
and should be supported at not more than five foot
intervals. Plumber’s tape, criss-crossed, will serve to
space both horizontal and vertical piping.

Gas vents supported only by the flashing and extend­ing above the roof more than five feet should be
securely guyed or braced to withstand snow and wind
loads. We recommend use of insulated vent pipe
spacer through the roofs and walls.

For protection against rain or blockage by snow, the
vent pipe must terminate with a vent cap which com­plies with the local codes or, in the absence of such
codes, to the latest edition of the National Fuel Gas
Code, ANSI Z223.1/NFPA 54.

The discharge opening must be a minimum of two feet
vertically from the roof surface and at least two feet
higher than any part of the building within ten feet.
Vent stack shall be at least five feet in vertical height
above the drafthood outlet. The vent cap location shall
have a minimum clearance of 4 feet horizontally from,
and in no case above or below, unless a 4-foot hor­izontal distance is maintained, from electric meters,
gas meters regulators and relief equipment.

Fig. 3: Indoor Drafthood

the cabinet is critical to proper operation.
Models 2100-4001 have built-in drafthoods that must
be properly vented to the outside.

WARNING: An indoor heater requires a drafthood
that must be connected to a vent pipe and properly
vented to the outside. Failure to follow this procedure
can cause fire or fatal carbon monoxide poisoning.

Vent Piping

Vent piping the same size or larger than the drafthood
outlet is recommended, however, when the total vent
height is at least ten (10) feet (drafthood relief opening
to vent terminal), the vent pipe size may be reduced
as specified in the National Fuel Gas Code, ANSI
Z223.1/NFPA 54 - latest edition. Avoid long horizontal
runs of vent pipe and too many elbows. If installa­tion requires horizontal or non-vertical runs, the vent

The weight of the vent stack or chimney must not rest
on heater drafthood. Support must be provided in
compliance with applicable codes. The heater top
and drafthood must be readily removable for mainte­nance and inspection. Vent pipe should be adequately
supported to maintain proper clearances from com­bustible construction.

Type “B” double-wall or equivalent vent pipe, certified
for Category I conditions, is recommended. However,
single-wall metal vent pipe may be used as specified
in the latest edition of the National Fuel Gas Code
ANSI Z223.1/NFPA 54.

10' OR LESS

2' MIN

VENT PIPE

DRAFT HOOD

HEATER

Fig. 4: Venting Clearances

VENT CAP

2' MIN

5' MIN

7

At the time of removal of an existing heater, the fol-

TRAP

lowing steps shall be followed with each appliance
remaining connected to the common venting system
placed in operation, while the other appliances remain­ing connected to the common venting system are not
in operation.

(a) Seal any unused openings in the common venting

system.

(b) Visually inspect the venting system for proper

size and horizontal pitch and determine there is
no blockage or restriction, leakage, corrosion and
other deficiencies which could cause an unsafe
condition.

(c) Insofar as is practical, close all building doors and

windows and all doors between the space in which
the appliances remaining connected to the com­mon venting system are located and other spaces
of the building. Turn on clothes dryers and any
appliance not connected to the common venting
system. Turn on any exhaust fans, such as range
hoods and bathroom exhausts, so they will oper­ate at maximum speed. Do not operate a summer
exhaust fan. Close fireplace dampers.

(d) Place in operation the appliance being inspected.

Follow the lighting instructions. Adjust thermostat
so appliance will operate continuously.

(e) Test for spillage at the drafthood relief opening

after 5 minutes of main burner operation. Use the
flame of a match or candle, or smoke from a ciga­rette, cigar or pipe.

(f) After it has been determined that each appliance

remaining connected to the common venting sys­tem properly vents when tested as outlined above,
return doors, windows, exhaust fans, fireplace
dampers and any other gas burning appliance to
their previous conditions of use.

(g) Any improper operation of the common venting

system should be corrected so the installation
conforms with the latest edition of the National
Fuel Gas Code, ANSI Z223.1/NFPA 54. When
re-sizing any portion of the common venting
system, the common venting system should be
re-sized to approach the minimum size as deter­mined using the appropriate tables in the National
Fuel Gas Code, ANSI Z223.1/NFPA 54.

For special venting applications that require reduced
vent sizes or through-the-wall venting, the optional D
Series Power Vent can be used. Consult the factory or
your local Raypak representative.

8

Gas Supply Connections

Per NFGC requirements, gas piping must have a
sediment trap ahead of the heater gas controls, and a
manual shut-off valve located outside the heater jack­et. All gas piping should be tested after installation in
accordance with local codes.

MANUAL

SHUT-OFF

VALV E

SEDIMENT

Fig. 5: Gas Piping

CAUTION: The heater and its manual shut-off
valve must be disconnected from the gas supply
during any pressure testing of that system at
test pressures in excess of 1/2 psig (3.45 KPA).
Dissipate test pressure in the gas supply line before
reconnecting the heater and its manual shut-off
valve to gas supply line. FAILURE TO FOLLOW
THIS PROCEDURE MAY DAMAGE THE GAS
VALVE. OVER PRESSURIZED GAS VALVES ARE
NOT COVERED BY WARRANTY. The heater and
its gas connections shall be leak tested before
placing the appliance in operation. Use soapy water
for leak test. DO NOT use open flame.

CAUTION: Do not use Teflon tape on gas line
pipe thread. A pipe compound rated for use with
natural and propane gases is recommended. Apply
sparingly only on male pipe ends, leaving the two
end threads bare.

A minimum of 7 in. WC and a maximum of 10.5 in. WC
upstream pressure under load, and no load conditions
must be provided for natural gas or a minimum of 11
in. WC and a maximum of 13 in. WC for propane gas.

Gas Pressure Regulator

The gas pressure regulator is preset and sealed at 4
in. WC for natural gas, and 11 in. WC for propane gas.
Between the gas valve and the burners is a 1/8” pipe
plug. The pressure at this point, taken with a manome­ter, should be about 3.7 in. WC natural gas and 10.5 in.
WC propane gas. If an adjustment is needed, remove

seal and turn adjustment screw clockwise
, to increase pressure or counter-clockwise
, to decrease pressure.

AT HEATER

MANUAL

SHUTOFF

VALV E

GAS PRESSURE

TEST UPSTREAM

GAS PRESSURE

TEST AT GAS

VALV E

GAS PRESSURE TEST

MANOMETER

Fig. 6: Gas Pressure Test Points

Venting of Diaphragm Gas
Components

Code. Under NO circumstances shall bleed lines ter­minate in the gas utilization equipment flue or exhaust
system.

Heaters with gastrain components that have dia­phragms in their construction are supplied with a bleed
line connection that must be connected to the outside
atmosphere as required by the National Fuel Gas

Model

No.

1” 1-1/4” 1-1/2” 2” 2-1/2” 3” 4”

N P N P N P N P N P N P N P

Bleed Line
Connection

Fig. 7: Bleed Line Connection

926/962 15 20 45 45 110 150 360 400

1083/1125 10 15 35 35 80 120 300 300

1178/1223 25 25 60 85 220 200

1287/1336 25 20 55 75 180 170 325 560

1414/1468 20 15 45 65 150 165 300 500

1571/1631 15 15 35 50 20 125 250 400

1758/1826 15 10 30 40 100 100 225 340

2100 10 10 25 30 80 75 175 260

2500 15 20 55 55 135 160 400 600

3001 10 15 35 40 85 120 250 500

3500 10 30 30 45 80 200 400 600

4001 5 20 25 35 65 160 300 400

Natural Gas, 1000 BTU/FT3 .60 Specific Gravity @ 0.5 in. WC Pressure Drop
Propane Gas, 2500 BTU/FT3 1.53 Specific Gravity @ 0.6 in. WC Pressure Drop

Table B: Maximum Equivalent Pipe Length

9

Water Connections

Location

Models 926-1223 With UG

The heater requires water flow and positive pressure
to fire and operate properly. It must therefore be
installed downstream of the discharge side of the filter
pump. A typical installation is plumbed as follows:

1. The inlet side of the filter is plumbed directly to the
discharge side of the filter pump;

2. The outlet side of the filter is then plumbed to the
inlet of the heater; and

3. The outlet of the heater is plumbed to the return
line to the pool or spa. The pump, filter and heater
are thus plumbed in series.

the low temperature piping. A fireman switch included
in the time clock may be used for this purpose with
instructions not to override this sequence manually.
See wiring diagram section for electrical hookup loca­tion of the fireman switch in the electrical circuit.

NOTE: If piping is used into the heater, this piping
(copper) must be anchored or screwed into the
flange (metal) if operating pressures above 30 PSI
are encountered.

All Models With H-Bypass or CWR

These heaters must be installed using primary/sec­ondary piping. For multiple-heater installations, use
reverse-return logic to ensure equal duty cycles. Flow
in the main line must be at least 120% of the heater
flow. See pages 16-17.

CONTROLS

Heater must be located so that any water leaks will not
damage the structure of adjacent area. High­temperature plastic pipe (CPVC) may be connected
directly into the heater, if local codes permit and if
controls operate the pump for at least fifteen minutes
after the heater is turned off.

CAUTION: NEVER install PVC directly into heater.
Four feet of copper or high temperature pipe and
two elbows are required between the heater and the
PVC connections. See Fig. 8 below.

Flow Switch

This dual purpose control shuts off the boiler in the
case of a pump failure or low water condition. It is
mounted and wired in series to the main gas valve.
Standard on all units except on UG models.

NOTE: Flow switch will not operate if flow is less
than:
Models 926-1223 60 gpm
Models 1287-1826 85 gpm
Models 2100-4001 180 gpm

Fig. 8: Plumbing

When local codes permit the use of less than four feet
of high-temperature piping or two elbows, provisions
should be made to always shut the heater off a min­imum of 15 minutes prior to pump shutdown in order
to carry away residual heat and prevent damage to

Fig. 9: Flow Switch

10

Water Pressure Switch

Unitherm Governor Operation

On Models 926-1223 built with a Unitherm Governor
(UG), a water pressure switch is provided in the heater
instead of a flow switch, to shut down the gas valves in
the event the water supply to the heater is interrupted.
It is very important to verify that the switch electrically
opens and shuts off the gas valve when water flow to
the heater is interrupted.

Otherwise, rapid and severe damage to the heater
will likely occur. (The water pressure switch should
be checked and adjusted for proper operation by a
qualified service person at the time of installation and
periodically checked thereafter. Refer to pressure
switch servicing instructions on page 24).

WARNING: Operation of the heater without water
circulation will cause rapid and severe damage to
the heater.

Automatic Chlorinators and
Chemical Feeders

All chemicals must be introduced and completely dilut­ed into the pool or spa water before being circulated
through the heater. Do not place chlorine tablets or
bromine sticks in the skimmer. High chemical concen­trations will result when the pump is not running (eg,
overnight).

Chlorinators must feed downstream of the heater and
have an anti-siphoning device to prevent chemical
backup into the heater when the pump is shut off.

NOTE: High chemical concentrates from feeders
and chlorinators that are out of adjustment will
cause very rapid corrosion to the heat exchanger in
the heater. Such damage is not covered under the
warranty.

The patented Unitherm Governor (UG) is a thermo­static mixing valve specifically designed to maintain
constant heater internal temperature between 105°
and 115°F despite continually changing flow rates from
the filter and changing pool temperatures. This narrow
range is needed to prevent damaging condensation on
the burners which will occur if the heater runs for any
length of time with an inlet temperature below 105°F.
It is also needed to inhibit scale formation in the tubes
by maintaining temperatures well below accelerated
scaling temperatures.

The Unitherm Governor is the default configuration on
models 926 through 1223. Where installed, it is built
into the inlet/outlet header. The larger sizes, models
1287 through 4001, do not have a UG option. Instead,
they have an externally-mounted bypass pump that is
designed to maintain the water entering the heater at
the proper temperature to prevent condensation and
scale. Thermometers are provided on the inlet and
outlet to the heater.

Companion Flange
Connections
(Models 926-1223 with UG)

DO NOT use petroleum base assembly fluids (such as
Petroleum Jelly or Lubricating Oil). If assembly lube is
required use a silicone base such as Armoral etc.

The inlet/outlet header flange accepts a 2” copper
tube as a slip connection directly into the header.
The flange is also threaded for a 2 NPT copper male
adapter.

Fig. 10: Companion Flange Connections

(Models 926–1223 with UG)

11

Fig. 11: Companion Flange Connections

2"
Ball

Pump

(Models 926/962–1287/1336 with H-Bypass)

3"

3"

Outlet

Inlet

Raypak recommends the installation of an air bleed
vent at a suitable location (usually the highest point in
the plumbing) to remove air from the piping system.
These units should be available at your local whole­sale supplier. Raypak does not provide this item.

CAUTION: Power to the heater should be
interlocked with the main system pump to make
sure the heater does not fire without the main
system pump in operation. Improper flow control can
damage the heater. Uncontrolled flow (too high) or
restricted flow (too low) can seriously affect heater
operation. Follow these instructions to make sure
your heater is properly installed.

Slip

Valve

Inlet/Outlet
Header

Fig. 12: Companion Flange Connections

(Models 2100–4001)

Model No.

926–1223

with UG

Connection

Size

2” FPT 60 100

Minimum

gpm

Maximum

1287–1826 2-1/2” FPT

Refer to Table D

2100–4001 3” FPT

Table C: Water Connections

Model No.

Loop* Flow Rates

(gpm)

Heater Flow
Rates (gpm)

1287/1336 30–50 85

1414/1468 35–55 85

1571/1631 40–65 85

1758/1826 45–70 85

2100 50–80 180

2500 60–95 180

2 H.P.

gpm

Models with H-bypass are equipped with an external
pump and bypass arrangement that blends outlet
water with the inlet to increase the inlet water tempera­ture, thereby reducing the likelihood of condensation
forming on the heat exchanger. The pump also serves
to circulate water through the heater from the main
system piping. Adjust the bypass to maintain 105ºF
inlet.

To complete the installation of the pool heater, the
poolstat needs to be installed in the main return water
line. This will ensure that the heater will be energized
at the right time. If the main water line is too far away
from the heater and the capillary bulb will not reach it,
locate the poolstat adjacent to the main line and run
wires back to the heater. Follow the instructions listed
below to install the poolstat.

Mounting the Poolstat Control
with Front-Mounted Loop
Using Mounting Slots

For heater models:
1287, 1336, 1414, 1468, 1571, 1631, 1758, 1826,
2100, 2500, 3001, 3500, 4001.

NOTE: For more detail on piping, refer to the
diagrams on pages 15, 16 & 17.

1. Remove the poolstat control cover by removing
the two cover screws at the top. See Fig. 13 & 14.

3001 75–115 180

3500 90–135 180

4001 100–150 180

*Loop is secondary piping to heater from main system.

Table D: Flow Rates

12

Fig. 13: Poolstat Control

Fig. 14: Control Cover

3. Remove either the left or right “knock-out” for wir­ing on the poolstat control as shown in Fig. 17.

Fig. 17: Remove Knockout

4. Attach appropriate conduit and connectors to the
poolstat control.

5. Attach wires to the poolstat wire terminals. See

2. Lace metal strapping or clamps, (NOT PROVIDED)
through the ¾” slots on the cover and fasten
securely to pipe as shown in Fig. 15 & 16. Do not
over-tighten clamps.

Fig. 15: Hose Clamp Slots

Fig. 18: Attach Wires

Fig. 18.

6. Install poolstat control to the cover and fasten
cover screws.

7. Poolstat should be mounted level as shown in Fig.

Fig. 16: Insert Clamps

Fig. 19: Mount Level

19.

13

Mounting Well into System
Return Loop Pipe - Front­Mounted Loop

1. Locate and mark an area on the main system

NOTE: For more detail on piping configurations for
large systems, refer to the diagrams on pages 15,
16 & 17.

return loop pipe where the well is always exposed
to the water circulating back from the pool. See
Fig. 20.

2. Shut off water and drain any water from the pipe

HEATER

Fig. 22: Installation with Weld O Lets

NOTE: The drawings and instructions above show
only one of several acceptable ways of installing
the dry well into main system loop. The use of
saddle clamps and “Weld O Lets” (shown in Fig.

22) are acceptable. Follow clamp manufacturer’s
instructions.

To adjust the temperature:

1. Both isolation valves must be fully open.

Fig. 20: Installation Location

as necessary.

3. Drill a 23/32” diameter hole (½” NPT) into the pipe
as shown in Fig. 21.

Fig. 21: Drill Hole in Pipe for Dry Well

4. Using a ½” NPT tap and appropriate handle,
thread the tap into the pipe.

5. Apply pipe dope as necessary to male threads
of well and insert into threaded hole. Do not
over-tighten well.

2. Adjust Bypass Valve “A” 1/2 open and Balancing
Valve “B” fully open. (See piping configuration
page 15, 16 & 17)

3. Fire your Raypak pool heater and adjust Bypass
Valve “A” to obtain a heater inlet temperature
approximately 105°F. Turning Valve A in the open
direction will raise the heater inlet temperature
and closing Valve “A” will lower the heater inlet
temperature.

CAUTION: The inlet water temperature must
be kept above 105°F. Changes in system flow or

valve position may require re-adjustment of the flow
settings. Check the heater bypass settings after
making adjustments. Failure to maintain an inlet
temperature above 105°F may result in damage to
the heater. Failure to comply with this instruction
voids the warranty.

4. If the heater inlet temperature remains less than
100°F and Valve “A” is fully open, leave Valve “A”
fully open and throttle Valve “B” until the heater
inlet temperature rises above 105°F.

5. The resultant heater outlet temperature should be
in the range of 120-130°F.

14

6. As the pool temperature rises to the desired tem-

Models 0926 thru 1223 with UG

perature as controlled by the Pool aquastat, small
adjustments to valves “A” and “B” will be required
for optimum performance. Heater temperatures
should be checked regularly to prevent heater
condensation. The heater inlet temperature can
be higher than 105°F without heater damage but
operating at less than 105°F inlet can cause dam­age from condensation.

NOTE: Consult factory if target temperatures cannot
be achieved.

Piping Configurations for Raytherm Commercial Pool Heaters

INTERNAL DIVERTING
BYPASS SYSTEM (UG)

4 PIPE

DIAMETERS

MAX.

15

Models 926-1826 with H-Bypass

ISOLATION VALVES FOR SERVICE

Piping Configurations for Raytherm Commercial Pool Heaters

4 PIPE

DIAMETERS

MAX.

4 PIPE

DIAMETERS

MAX.

TI

To

4 PIPE

DIAMETERS

MAX.

BLENDED WATER TEMPERATURE
(THERMOMETER AT HEATER INLET)

HEATER OUTLET TEMPERATURE
THERMOMETER

Tc

HEATER THERMOSTAT

RECOMMENDED FIELD INSTALLED

16

ISOLATION VALVES FOR SERVICE

Models 2100 thru 4001 with H-Bypass

Piping Configurations for Raytherm Commercial Pool Heaters

4 PIPE

DIAMETERS

MAX.

4 PIPE

DIAMETERS

MAX.

TI

To

4 PIPE

DIAMETERS

MAX.

BLENDED WATER TEMPERATURE
(THERMOMETER AT HEATER INLET)

HEATER OUTLET TEMPERATURE
THERMOMETER

Tc

HEATER THERMOSTAT

RECOMMENDED FIELD INSTALLED

17

External Auxiliary Bypass
Valve (Where Required)
926-1223 Models Only

An auxiliary bypass valve should be used when flow
rates exceed 100 gpm (usually a high performance
pump size larger than two HP will exceed this flow
rate). This valve is required to complement the func­tion of the automatic bypass valve, particularly when
starting the heater in winter or early spring when the
spa or pool temperature is below 55°F. It also serves
to eliminate needless pressure drop through the heat­er and accompanying reduction in the flow rate to the
spa jets, etc.

Bypass Valve

Open Position

Fig. 24: Manual Bypass Valve on UG models

Closed Position

Fig. 23: Auxiliary Bypass Valve

Auxiliary Bypass Valve
Adjustment

To set bypass: With clean filter, adjustment is made by
feeling the inlet and outlet pipes at the heater. Outlet
pipes should be slightly warmer than inlet and comfort­able to the touch. If pipe is hot, close bypass; if cold,
open bypass.

NOTE: Do not use a gate valve as an auxiliary
bypass valve on any heaters.

Models 926-1223 with UG

The heater is also equipped with a manual bypass
built into the header. This is in addition to the automat­ic bypass valve. This may be used with flow rates up
to 100 gpm and adjusted as below.

NOTE: Sooting or liming caused by improper
bypass adjustment voids the warranty.

NOTE: To avoid water damage or scalding due to
valve operation, drain pipe must be connected to
valve outlet and run to a safe place of discharge.
Drain pipe must be the same size as the valve
discharge connection throughout its entire length
and must pitch downward from the valve. No shut-off
valve shall be installed between the relief valve and
the drain line. Valve lever should be tripped at least
once a year to ensure that waterways are clear.

Temperature Controls

High Limits

The pool heater is equipped with two high limits. Both
high limits, the non-adjustable auto reset high limit and
adjustable manual reset high limit are attached to the
outlet side of the in/out header.

Poolstat

The pool heater is equipped with a poolstat that is
attached to the inlet side of the in/out header to control
the pool temperature.

18

Low Water Cutoff

Automatically shuts down burner whenever water
level drops below probe. A 3 to 5 second time delay
prevents premature lockout due to temporary condi­tions such as power failure or air pockets. Standard
on Cal Code heaters.

Fig. 25: Low Water Cutoff

High & Low Gas Pressure Switches

Pressure switches sense either high or low gas pres­sure and automatically shut down burners if abnormal
pressures exist. Standard on Models 3001-4001.

CAUTION: Label all wires prior to disconnection
when servicing controls. Wiring errors can cause
improper and dangerous operation. Verify proper
operation after servicing.

NOTE: If it is necessary to replace any of the
original wiring, it must be replaced with 105° C wire
or its equivalent.

NOTE: Models 2100-4001 require 240VAC power
to the pump.

Electronic Ignition

The intermittent ignition device conserves energy by
automatically extinguishing the pilot when desired
temperature is reached. When additional heat is need­ed, the pilot re-ignites electrically, eliminating the fuel
costs of maintaining a constant pilot. To ensure safe
operation, the gas valve cannot open until the pilot
relights and is confirmed.
Heater must be electrically grounded and bonded

Without Lockout With Lockout

Model

N P N P

926–1826 Standard N/A Optional Standard

2100–4001 N/A N/A Standard Standard

Fig. 26: High/Low Gas Pressure Switch

Electrical Wiring

DANGER - SHOCK HAZARD - Make sure

electrical power to the heater is disconnected to avoid
potential serious injury or damage to components.

Table E: Lockout Availability

in accordance with local codes, or, in the absence
of local codes, with the latest edition of the National
Electrical Code, ANSI/NFPA 70.

The heater draws less than 1 amp - not includ­ing the pump power - when operating on either
120VAC or 240VAC power.

Fig. 27: Ignition Module

19

Wiring Diagram—Models 926–1223 with UG

20

Wiring Diagram—Models 926–1826 with H-Bypass

21

Wiring Diagram—Models 2100–2500

22

Wiring Diagram—Models 3001–4001

23

SERVICING

Temperature Control

General Location Of Controls

Models 926-1223 with UG

Fig. 28: General Location of Controls

(Models 926-1223 with UG)

Models 2100-4001

Inlet/Outlet
Header w/Bypass
Pump

The pool water temperature is controlled by the
poolstat. The heater water temperature high limit is
controlled by the manual reset high limit.

Pressure Switch

The pressure switch on a unit equipped with a
Unitherm Governor ensures that the heater operates
only when the filter pump is in operation. It is factory
set at 1.75 PSI for deck level installations. When the
heater is located below the level of the spa or pool,
it may be necessary to reset the pressure switch to
compensate for the no-flow static head. See Fig. 31.
If it is necessary to reset the pressure switch, we rec­ommend the following procedure.

Pressure Switch Adjustment

1. Make sure the pool filter is clean before adjusting
the switch.

2. Set the heater control to the OFF mode.

3. Turn the filter pump on and confirm that the pres­sure switch is closed (use a multimeter to check).
If the pressure switch fails to close, either the
switch setting is too high or the filter pump is not
supplying enough pressure.

Electrical

Connection

Main Burner

Gas ValveManual On/Off Valve

Fig. 29: General Location of Controls

(Models 2100-4001)

4. Turn the heater ON.

5. Manually turn the pressure adjustment knob clock­wise (see Fig. 30) until the heater shuts off. (A flat
screw driver may be necessary if knob is too tight).

6. Slowly turn the adjustment knob counter-clock­wise until the heater calls for heat again.

7. Turn an additional 1/2 turn counter-clockwise.

8. While the heater is running, check the adjustment
by turning the pump off and on several times. The
burners should shut off immediately when the
pump is turned off. If it does not, repeat the above
steps until proper operation is observed.

24

A

DJUSTMENT KNOB

Fig. 30: Pressure Switch Adjustment

5’ Max

START-UP
PROCEDURES

Before Start-Up

Burners

Clean main burners and air louvers of dust, lint and
debris. Keep heater area clear and free from com­bustibles, flammable liquids, and chemicals. Do not
obstruct the flow of combustion and ventilating air.

Water

Water must be flowing through the heater.

Start-Up

5’ Max

CAUTION: Propane gas is heavier than air and
sinks to the ground. Exercise extreme care in lighting
heater in confined areas.

Fig. 31: Heat Exchanger Height Above/Below Pool

NOTE: If heater is installed outside of the limits
shown, a flow switch must be used in place of the
pressure switch when mounted and wired adjacent
to the heater.

Two-Speed Pumps

In some cases, the flow on the low speed is insufficient
to operate the heater. This is apparent when the pres­sure switch cannot be further adjusted or if the heater
makes banging noises. In these cases, the pump must
be run at high speed when heating the water.

CAUTION: Do not operate a UG-equipped heater
without properly-adjusted pressure switch.

Pilot Safety

Lighting Instructions

1. Close all gas valves. Turn off electric power supply
wait 5 minutes.

2. Open manual pilot valve. Turn on electric power,
pilot is automatically lighted.

3. Open main gas valve.

4. Set temperature controls to desired temperature.

To Shut Down

Close all manual gas valves. Turn off electric power.

The heater employs a pilot safety which closes the
main gas valve within 8/10ths of a second whenever
the pilot flame is interrupted. Pilot flame is automatical­ly lit when the device is powered. Unit performs its own
safety check and opens the main valve only after the
pilot is proven to be lit.

25

After Start-Up

INSPECTION

Pilot System Checkout Procedure

1. Turn on power to the ignition systems and turn gas
supply off.

2. Check ignition module as follows:

a. Set the poolstat above pool water temperature

to turn heater on.

b. Watch for continuous spark at the pilot burner.

c. Time the spark operation. Time must be within

the lockout timing period (15 or 90 seconds).

d. Turn poolstat down to turn off heater and wait

60 seconds on lockout models before begin­ning step 3.

3. Turn on gas supply.

4. Set poolstat above pool water temperature to turn
on heater.

5. Systems should start as follows:

PROCEDURES

Burners

Clean main burners and air louvers of dust, lint and
debris. Keep heater area clear and free from combus­tibles and flammable liquids. Do not obstruct the flow
of combustion and ventilating air. Make visual check of
burner and pilot flame. Yellow flame indicates
clogging of air openings. Lifting or blowing flame indi­cates high gas pressure. Low flame indicates low gas
pressure.

Fig. 32: Main Burner Flame

a. Spark will turn on and pilot gas valve will open

at once. Pilot burner should ignite after gas
reaches the pilot burner.

b. Spark ignition should cut off when pilot flame

is established.

c. Main gas valve should open and main burner

should ignite after gas reaches the burner
port.

Fig. 33: Pilot Burner Flame

Feel inlet and outlet pipes. Outlet should be only slight­ly warmer than inlet. It should not be hot.

WARNING: Should overheating occur or the gas
supply fails to shut off, turn off the manual gas
control to the appliance.

CONTROLS

Check all controls to see that they are operational. To
check electric safety turn off main burner. Observe
pilot burner when shutting off pilot gas. Ignition spark
should go on. Main gas valve will also drop out.

26

SERVICING

Burner Drawer Removal

PROCEDURES

Tube Cleaning Procedure
(Typical)

Establish a regular inspection schedule, the frequency
depending on the local water condition and severity of
service. Do not let the tubes clog up solidly. Clean out
deposits over 1/16” in thickness.

Although the illustration shows the mechanical clean­ing procedure of a small heater, it is typical of all sizes.
The heater may be cleaned from the return header
side as shown, without breaking pipe connections. It is
preferable, however, to remove both headers for better
visibility through the tubes and to be sure the ground
up lime dust does not get into the system.

Note that you do not remove the top pan or the heat
exchanger, generally.

After reaming, mount the wire brush in lieu of the
auger and clean out the debris remaining in the tubes.
Another method is to remove the heat exchanger,
ream tubes and immerse heat exchanger in non-inhib­ited de-scale solvent.

1. Shut off power and gas supply to the pool heater.
Disconnect union(s) and pilot tubing, then loosen
and remove burner-hold down screws.

2. Disconnect wires at gas valve and slide burner
drawer out.

Gas Valve Removal

1. Shut off gas supply to the pool heater. Remove
gas piping to gas valve inlet.

2. Disconnect wires, pilot tubing and bleed line, if
required.

3. Turn vertical gas pipe from manifold slightly and
unscrew gas valve.

4. Reverse above procedure to re-install.

RAYPAK TUBE CLEANING KIT

Extension Pieces (5) Auger with Carbide Tip Wire Brush

Fig. 34: Tube Cleaning Kit

Fig. 35: Tube Cleaning Procedure

27

Main Burner and Orifice
Removal

1. Remove screws and burner hold down bracket.
NOTE: If the heat exchanger is sooted badly, the
burner hold-down bracket and spacer can become
distorted from direct flame impingement and this
usually necessitates replacement of these parts.

Heat Exchanger Reassembly

1. Heat exchanger header O-rings should be replaced
with new ones.

2. Install inlet-outlet and return water headers and
install header retainer nuts and torque nuts even­ly.

2. Lift burners from slotted spacer and slide from
orifices. Clean with a wire brush.

3. Orifices usually do not need to be replaced. To
clean, run either copper wire or wood through ori­fice. Do not enlarge hole. To remove orifice, use a
socket wrench and remove the manifold. DO NOT
overtighten when reinstalling.

Pilot Removal and Cleaning

1. Disconnect pilot tubing at pilot and sensor/igniter
wire. Remove screws holding pilot bracket to burn­er drawer.

2. Remove pilot and bracket, clean pilot of debris,
small bugs, etc., with wire or small brush.

3. Replace pilot, pilot tubing, sensor ignition wires
and check for leaks.

Heat Exchanger Removal

1. Shut water, gas and electricity off, close valves,
relieve pressure and remove relief valve. Remove
side inspection panels.

2. Remove top holding screws.

3. Install the four (4) corner clips between tube
sheets and refractory. Replace “V” baffles.

4. Install thermostat sensing bulbs in header wells
and replace bulb retaining clips.

5. Install inlet and return pipes in water headers
using pipe thread sealant.

6. Install water pressure relief valve, flow switch, and
low water cutoff devices if so equipped.

7. Open water supply and return shutoff valves. Fill
heater and water piping system with water. Check
heater and piping system for leaks at full line pres­sure. Run system circulating pump for a minimum
of 1/2 hour with heater shutoff.

8. Shut down entire system and vent all radiation
units and high points in system piping. Check all
strainers for debris.

9. Install flue collector, jacket top and inspection pan­els. Install top holding screws. Install draft diverter
and vent piping if so equipped.

10. If gas piping was disconnected, reconnect gas
piping system and check for leakage using a soap
solution.

3. Remove draft diverter, lift and remove top and flue
collector on stack type models. Remove inspec­tion panels.

4. Loosen bolts and disconnect flange nuts on inlet/
outlet header, loosen union(s) at gas pipe, and
slide heater away from piping until studs clear the
heater.

5. Remove heat exchanger corner brackets.

6. Remove combustion chamber clips at the four
corners of the heat exchanger.

7. Lift heat exchanger straight up using caution not to
damage refractory.

11. Double check electrical circuits, grounding con­nections and pump with wiring diagram supplied
with heater.

12. Check for correct water pressure and water level
in the system. Make sure that system pump oper­ates immediately on the call for heat. The system
is ready for operation.

28

Combustion Chamber Removal

To remove the combustion chamber you must first
have removed the heat exchanger. Unbolt metal
combustion chamber retainer from top and remove
combustion chamber panels individually.

Fig. 36: Refractory Panels—Top View

Control Well Replacement

canopy and flue collector off (on models 926-1826,
remove the canopy hold-down brackets). Remove “V”
baffles over tube(s) to be replaced. If no pipe unions
have been provided, use the header as a union,
remove the flange nuts off the inlet-outlet header,
break gas connection and slide heater away from
piping, allowing room to work. Pull wedge clips out
of control wells and remove sensing bulbs. Remove
flange nuts from the return header and remove head­er. Lift heat exchanger straight up and out.

Heat exchanger header o-rings must be replaced with
new ones. The tube may be cut out with a hack-saw or
hammer and chisel adjacent to both tube sheets, leav­ing stubs in the tube sheets. Then proceed to collapse
stubs in the tube sheets with a chisel or screwdriver.
Use caution not to cut into the tube sheet. Replacement
tubes will have the fins stripped off longer on one end.
The long end is inserted into the opening of the tube
sheet first; then the short end is fitted through the
opposite tube sheet. If the tube ends become dented
or bent, straighten at least four (4) inches back from
the tube end by means of a tapered punch.

Remove top, sensing bulb and clip. Collapse well
tube at the open end and with a chisel, push through
into the header, and remove the well through header.
Insert a new well and roll into place. If a roller is not
available, solder the well in place with silver solder.

Fig. 37: Immersion Well

Tube Replacement Procedure

On Raypak tube replacement may be affected without
rolling, as a temporary means of repair, provided there
are two or more tubes rolled into act as stays on left
and right sides. The “O” rings should provide a seal up
to 125 PSI working pressure. Use a 3/8” heavy duty
reversible drill motor or larger, to power the tube roller.
If a reversible drill is not available, after rolling the tube
in, remove the drill motor and wrench out the roller. A
tube roller is available from the factory.

Insert tube roller into tube opening up to stop against
tube, then push center rod in until roller is tight. Be
careful to keep replacement tube squared up 1/8” out­side each tube sheet. A loose tube will sometimes pull
toward the roller. Attach drill motor to tube roller, hold­ing it straight and level. Proceed to expand tube until
the tool begins to grab. At this point, 1/2” to 1” should
be exposed on the tool shank. Reverse drill motor
or wrench out by hand. Care should be exercised to
avoid applying excessive torque during rolling opera­tion and to avoid thinning out any part of the tube wall
excessively over .015”. Use same procedure at the
opposite end of the tube.

Apply line pressure test, and re-roll, if necessary,
before replacing canopy.

Procedure For Cleaning Flue
Gas Passageways

Soot can clog areas behind fins and cause eventual
tube failure. Any sign of soot at base of burners or
around outer jacket indicates a need for cleaning.

1. Lift off drafthood and flue collector by removing
bolts and screws.

2. Remove “V” baffles from heat exchanger.

Shut gas and power off to the unit, close the system
off and drain the pool heater. Remove draft diverter.
Remove the access panels and jacket top. Lift the

3. Remove burner tray.

4. Take garden hose and wash heat exchanger,

29

making sure soot is removed from between fins.
(Avoid excessive water against refractory).

5. Reassemble; when heater is fired, some steam will
form from wet refractory. This is normal.

MAINTENANCE AND
CARE

To be followed one month after initial start-up and then
quarterly.

NOTE: In extreme cases it may be necessary to
remove the heat exchanger completely for cleaning.
The simplest method is steam cleaning at a local car
wash. DO NOT WIRE BRUSH!

CAUTION: Soot is combustible, so exercise
extreme care.

Unitherm Governor
Replacement

1. Shut off water, gas and electricity, close valves,
relieve pressure.

2. Drain heat exchanger.

3. Remove Unitherm Governor.

1. Inspect top of heater and draft-hood for soot, and
open fuel gas passageways.

2. Clean main burners and pilot burner of dust and
lint.

CAUTION: Soot may be combustible. Wet com­pletely when cleaning.

3. Inspect and operate all controls and gas valve.

4. Make visual check of burner and pilot flame.
Flame pattern on main burner and pilot is indicat­ed on page 26. Yellow flame means restriction
of air openings. Lifting or blowing flame indicates
high gas pressure. Low flame means low gas
pressure.

5. Clean room air intake openings to ensure ade­quate flow of combustion and ventilation air.

6. Remove header opposite inlet pipes when clean­ing and inspect internal tubes for scale deposits.
If scale does not form within first quarterly inspec­tion, then inspect annually thereafter.

Fig. 38: Unitherm Governor—Models 926–1223

To test operation of Unitherm Governor, place in hot
water (110°F or higher) and watch for movement
against spring. If no movement, replace.

CAUTION: Combustion air must not be
contaminated by corrosive chemical fumes which
can damage the heater and void the warranty.

7. Keep heater air clear and free from combustible
materials and other flammable and corrosive
vapors and liquids.

8. Keep moving parts lubricated.

9. Manual operation of pressure/temperature relief
valve at least once a year.

30

Winterizing Your Heater

When heaters installed outdoors in freezing climate
areas are to be shut down for the winter, please
observe the following step-by-step procedure:

1. Remove the drain plug or open the drain cock
located on the inlet-outlet header. On larger
heaters with external Unitherm Governor(s) and
piping, locate plug at low point of Governor piping,
or break connections and rotate inlet fittings 180
degrees to face downward. Turn off manual main
gas and main gas shut off.

2. On units equipped with a UG (models 926-1223),
locate the pressure switch. Disconnect the com­pression fittings on both ends of the 1/8” copper
tube and allow the tube to drain. Remove the “heat
exchanger inspection panels” on the right side of
the heater to gain access to the fitting on the return
header. Remove the return header to ensure that
no water remains in the heat exchanger.

31

IMPORTANT NOTICE

*Usually occurs on initial start-up

TROUBLESHOOTING

These instructions are primarily intended for the use of qualified personnel specifically trained and experienced
in the installation of this type of heating equipment and related system components. Installation and service
personnel may be required by some states to be licensed. Persons not qualified shall not attempt to install this
equipment nor attempt repairs according to these instructions.

MECHANICAL (FOR QUALIFIED SERVICE PERSONNEL ONLY)

PROBLEM

Harmonics, or whining noise

Heater going on and off
continously

Liming or scale forming on
heat exchanger

Sooting

CAUSE

U.G. Inoperative……………………

*Debris or restriction in system……

*Debris in gas line…………………..
Low flow……………………………...

Dirty filter……………………………
Low water level in pool..……………
External bypass setting out of
adjustment…………………………..
*Pressure switch out of
adjustment…………………………..

Pool water…………………………....

High flow rates…………………….....

U.G. Inoperative……………………..

*Air starvation………………………..

*Improper venting…………………....

*Insects or debris clogging
burner intake ports…………………..

SOLUTION

Check movement by putting in hot
water (110°F or higher). If no move­ment, replace.
Locate the restriction and remove.
Flush system and clean.
Remove debris or blow out gas line.
Scale forming in heat exchanger ­clean heat exchanger and check
pool pH and total alkalinity.

Backwash filter.
Raise water level.

Adjust bypass

Adjust pressure switch

Recommended pH should be be­tween 7.3 and 7.8 total alkalinity 100­150 PPM maximum. Hardness -150­400 PPM maximum. (see page 2)

Reduce by adding manual bypass
valve and adjust by putting ther­mometer in header (1/4" NPT) drain
opening. Set bypass so thermome­ter reads between 105° and 110°F.
Check movement by putting in hot
water (110°F or higher). If no move­ment, replace.
Refer to installation instructions.
Follow recommended installation
instructions.

Clean burners

Pilot outage

Yellow lazy flame

Low gas pressure…………………....

Restricted pilot……………………....

Weak pilot generator………………..

Low gas pressure…………………....

*Insects or debris clogging
burner intake ports…………………..

32

Adjust gas pressure.
Clean pilot.
Replace pilot.

Adjust gas pressure.

Clean burners.

Outer jacket very hot
(paint blistered)

*Broken refractory caused by

heat

no

when

water

main-

cor-

Limin

Leaking at well.

Leaking

Gasket brittle and leaking­(overheated)

Takes long time to heat pool
or spa

shipping damage or improper
combustion…………………………..
Excessive sooting of heat
exchanger…………………………...

Calculate temperature in °F/hr……...

Filter not running long enough……....

Dirty filter……………………………..
Gas line or meter under-

sized………..................................

Replace refractory panels.

Determine cause of sooting &
correct.
Heat rise (°F/hr.) =

Htr.output

Pool gallonage x 8.33
or refer to heater sizing chart.
This does not take into account
loss due to weather.
Reset time clock.
Clean filter.

Refer to installation instructions.

g

at heat exchanger.

Bypassing too much water………....

Inspect bypass for movement, if
movement, replace.

U/G not functioning……………….....

Replace if no movement
heated.

Overacid…………………………......

Replace well and maintain
chemistry properly.

Overacid……………………………...

Replace heat exchanger and
tain chemistry properly.

.

Heater running after pump
shuts off……………………………...
Refractory damage………………….
Sooted heater………………………..

See pressure switch adjustment.
Replace refractory.
Determine cause of sooting and
rect.

*Usually occurs on initial start-up

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ENDS

ELECTRICAL (ELECTRONIC IGNITION IID) IID

Intermittent Pilot System

TROUBLESHOOTING HONEYWELL S8600

WARNING: HIGH VOLTAGE. For qualified
technicians ONLY.

NOTE: Some heaters may be equipped with an
ignition module that shuts off pilot gas if the pilot fails
to light. To reset, interrupt power to the heater.

START

TURN GAS SUPPLY OFF.

TURN THERMOSTAT

(CONTROLLER) TO CALL

FOR HEAT

POWER TO MODULE

(24 V NOMINAL)

YES

SPARK ACROSS

IGNITER/SENSOR GAP

YES

TURN GAS SUPPLY ON

PILOT BURNER LIGHTS?

YES

SPARK STOPS WHEN

PILOT IS LIT?

YES

NOTE: Before troubleshooting, familiarize yourself with the start-up and checkout
procedure.

Check line voltage power, low voltage transformer, limit controller, thermostat

NO

(controller) and wiring.

Pull ignition lead and check spark at module.

NO

Spark Okay?
YES

• Check ignition cable, ground wiring, ceramic insulator and gap, and correct.

• Check boot of the ignition cable for signs of melting or buckling. Take protective
action to shield cable and boot from excessive temperatures.

• Check that all manual gas valves are open, supply tubing and pressures are

NO

good, and pilot burner orifice is not blocked.

• Check electrical connections between module and pilot operator on gas control.

• Check for 24 Vac across PV-MV/PV terminals on module. If voltage is okay,
replace gas control; if not, replace module.

NOTE: If S8600H goes into lockout, reset system by removing power for at least
60 seconds. Lockout is used on Pro. models.

• Check continuity of ignition cable and ground wire.

NO

• Clean flame rod.

• Check electrical connections between flame rod and module.

• Check for cracked ceramic flame rod insulator.

• Check that pilot flame covers flame rod and is steady and blue.

• Adjust pilot flame.

• If problem persists, replace module.

• Check for 24 Vac across MV-MV/PV terminals. If no voltage, replace module.

MAIN BURNER LIGHTS?

YES

SYSTEM RUNS UNTIL

CALL FOR HEAT ENDS?

YES

CALL FOR HEAT ENDS

SYSTEM SHUTS OFF?

YES

TROUBLESHOOTING

NO

• Check electrical connections between module and gas control. If okay, replace
gas valve or gas control operator, i.e. pilot gas valve, flow switch etc.

NOTE: IF S8600H goes into lockout, reset system.

NO

• Check continuity of ignition cable and ground wire.

NOTE: If ground is poor or erratic, shutdowns may occur occasionally even though
operation is normal at the time of checkout.

• Check that pilot flame covers flame rod and is steady and blue.

• If checks are okay, replace module.

• Check for proper thermostat (controller) operation.

NO

• Remove MV lead at module; if valve closes, recheck temperature controller and
wiring; if not, replace gas valve.

Repeat procedure until trouble free operation is obtained.

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www.raypak.com

Raypak, Inc., 2151 Eastman Avenue, Oxnard, CA 93030 [phone] Fax [phone]

Litho in U.S.A.

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