Lochinvar 90,000Btu Service Manual

Installation & Service Manual

Models: 90,000 - 500,000 Btu/hr

This manual supplies information for the
installation, operation, and servicing of the
appliance. It is strongly recommended that this
manual be reviewed completely before proceeding
with an installation. Perform steps in the order
given. Failure to comply could result in severe
personal injury, death, or substantial property
damage.

 WARNING:

Save this manual for future reference.

CFA-I-S Rev A

2

Hazard definitions

The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk levels
or to important information concerning the life of the product.

 DANGER

 WARNING

 CAUTION

CAUTION

NOTICE

DANGER indicates an imminently hazardous situation which, if not avoided, will result in death or serious
injury.

WARNING indicates a potentially hazardous situation which, if not avoided, could result in death or serious
injury.

CAUTION indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate
injury.

CAUTION used without the safety alert symbol indicates a potentially hazardous situation which, if not
avoided, may result in property damage.

NOTICE indicates special instructions on installation, operation, or maintenance that are important but not
related to personal injury or property damage.

Contents

HAZARD DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . 2

PLEASE READ BEFORE PROCEEDING . . . . . . . . . . . . 3-4

RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6

THE COPPER-FIN --HOW IT WORKS . . . . . . . . . . . . . . . . . 7-9

1. DETERMINE UNIT LOCATION

Locate of Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Clearances from Combustible Construction . . . . . . . . . . .10

Combustion and Ventilation Air . . . . . . . . . . . . . . . . . . . . 11-13

2. VENTING

A Conventional Negative Draft Venting System . . . . . . . 14-15

Vertical Vent Termination Clearances . . . . . . . . . . . . . . . 16

Masonry Chimney Installation . . . . . . . . . . . . . . . . . . . . . 17

Inspection of a Masonry Chimney . . . . . . . . . . . . . . . 17

Automatic Vent Damper . . . . . . . . . . . . . . . . . . . . . . . . . . 18

3. GAS CONNECTIONS

Gas Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Gas Pressure Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Gas Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Gas Manifold Pressure Adjustment Procedure . . . . . . . . 21

Checking Gas Supply Pressure . . . . . . . . . . . . . . . . . . . 22

Combination Gas Valves . . . . . . . . . . . . . . . . . . . . . . . . . 23

4. HYDRONIC PIPING

Relief Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Water Flow Switch (if equipped) . . . . . . . . . . . . . . . . . . . 24

Low Water Cutoff (if equipped) . . . . . . . . . . . . . . . . . . . . 25

Typical Heating Boiler Installations . . . . . . . . . . . . . . . . . 25-26

Piping of the Boiler System . . . . . . . . . . . . . . . . . . . . . . . 26

Water Connections Heating Boilers Only . . . . . . . . . . . . 27

Circulator Pump Requirements . . . . . . . . . . . . . . . . . . . . 27

Circulator Pump Specifications . . . . . . . . . . . . . . . . . . . 27

Circulator Pump Operation (Heating Boilers Only) . . . . 27

Primary/Secondary Boiler Piping . . . . . . . . . . . . . . . . . . . 28

Low Temperature Bypass Requirements . . . . . . . . . . . . . 28

Three Way Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Boiler Flow Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Figure 4-6_Prim. / Sec. Piping of a Single Boiler . . . 30
Figure 4-7_Prim. / Sec. Piping w/Low Temp. Bypass 31

Figure 4-8_Multiple Boilers Zoned w/Circulators . . . . 32

5. ELECTRICAL CONNECTIONS

Boiler Operating Temperature Control . . . . . . . . . . . . . . . 33

Room Thermostat or Remote Thermostat Connection . . 33

Power Venter Connection to Terminal Strip . . . . . . . . . . . 33

Pump Wiring for a Heating Boiler . . . . . . . . . . . . . . . . . . 34

Temperature Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . 34

Temperature Control Settings . . . . . . . . . . . . . . . . . . . . . 35

Maximum Set Point Determination . . . . . . . . . . . . . . . . . 35

Outdoor Air Reset Option . . . . . . . . . . . . . . . . . . . . . . . . 36

Additional Temperature Controls . . . . . . . . . . . . . . . . . . . 38-39

Blocked Vent and Flame Roll-Out / Flame Interlock Switch . 39

6. STARTUP

Initial Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Lighting Instructions for Standing Pilot Models (F1) . . . . 40-42

Safety Shutoff Test for Standing Pilot Ignition System . . 42
Lighting Instructions for Spark Ignition Pilot Models (F9/M9) . 43-44

Safety Shutoff Test for Spark Ignition Pilot System . . . . . . 44

Intermittent Pilot Spark Ignition System (F9/M9) . . . . . . . . . 44-45

Freeze Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Water Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

7. DOMESTIC WATER HEATERS

Water Velocity Control . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Required Temperature Rise . . . . . . . . . . . . . . . . . . . . . . . 46

Water Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Softened Water Systems . . . . . . . . . . . . . . . . . . . . . . . . . 47

Pump Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Figure 7-1_Single Water Heater Piping w/Single Tank . . 48
Figure 7-2_Single Water Heater Piping w/Multiple Tanks 49
Figure 7-3_Multiple Water Heater Piping w/Single Tank . 50

Remote Sensor Installation . . . . . . . . . . . . . . . . . . . . . . . 51

Heat Exchanger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Thermostat Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51-52

Optional Relief Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Thermal Expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Cathodic Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

8. MAINTENANCE

Maintenance and Annual Startup . . . . . . . . . . . . . . . . . . 54-60

9. TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . 61-62

10. DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63-66

3

Installation & Service Manual

Please read before proceeding

NOTICE

This is a gas appliance and should be
installed by a licensed electrician and/or
certified gas supplier. Service must be
performed by a qualified service installer,
service agency or the gas supplier.

 WARNING

If the information in these instructions is
not followed exactly, a fire or explosion may
result causing property damage, personal
injury, or death.

This appliance MUST NOT be installed in
any location where gasoline or flammable
vapors are likely to be present, unless the
installation is such to eliminate the probable
ignition of gasoline or flammable vapors.

What to do if you smell gas –

• Do not try to light any appliance.

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

• Immediately call your gas supplier from a near by 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.

Warranty –

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

Factory warranty (shipped with unit) does not apply to units
improperly installed or improperly operated.

Experience has shown that improper installation or system
design, rather than faulty equipment, is the cause of most
operating problems.

1. Excessive water hardness causing a lime/scale build-up in

the copper tube is not the fault of the equipment and is
not covered under the manufacturer’s warranty (see
Water Treatment and Water Chemistry).

2. Excessive pitting and erosion on the inside of the copper

tube may be caused by too much water velocity through
the tubes and is not covered by the manufacturer’s
warranty (see Boiler Flow Rates and Temperature Rise for
flow requirements).

Checking equipment –

Upon receiving equipment, check for signs of shipping damage.
Pay particular attention to parts accompanying the appliances
which may show signs of being hit or otherwise being
mishandled. Verify total number of pieces shown on the
packing slip with those actually received. In case there is damage
or a shortage, immediately notify the carrier.

Do not use this appliance if any part has been under water.
The possible damage to a flooded appliance can be extensive
and present numerous safety hazards. Any appliance that has
been under water must be replaced.

 WARNING

Improper installation, adjustment,
alteration, service or maintenance can cause
injury or property damage. Refer to this
manual for assistance or additional
information, consult a qualified installer,
service agency or the gas supplier.

 Owner warning –

NOTE: Retain this manual for future reference.

The information contained in this manual is intended for use by
qualified professional installers, service technicians, or gas
suppliers. Consult your local expert for proper installation or

service procedures.

IMPORTANT

Consult and follow all local Building and
Fire Regulations and other Safety Codes
that apply to this installation. Consult your
local gas utility company to authorize and
inspect all gas and flue connections.

Your conventionally vented gas appliance must have a supply of
fresh air circulating around it during burner operation for
proper gas combustion and proper venting.

 WARNING

Should overheating occur or the gas supply
fail to shut off, do not turn off or disconnect
the electrical supply to the pump. Instead,
shut off the gas supply at a location external
to the appliance.

4

Installation & Service Manual

Please read before proceeding

 WARNING

To minimize the possibility of serious
personal injury, fire, or damage to your
appliance, never violate the following safety
rules:

1. Boilers and water heaters are heat
producing appliances. To avoid damage
or injury, do not store materials against
the appliance or the vent-air intake
system. Use proper care to avoid
unnecessary contact (especially children)
with the appliance and vent-air intake
components.

2. Never cover your appliance, lean
anything against it, store trash or debris
near it, stand on it or in any way block
the flow of fresh air to your appliance.

3. UNDER NO CIRCUMSTANCES must
flammable materials such as gasoline or
paint thinner be used or stored in the
vicinity of this appliance, vent-air intake
system or any location from which fumes
could reach the appliance or vent-air
intake system.

Codes –

The equipment shall be installed in accordance with those
installation regulations in force in the local area where the
installation is to be made. These regulations shall be carefully
followed in all cases. Authorities having jurisdiction shall be
consulted before installations are made. In the absence of such
requirements, the installation shall conform to the latest edition
of the National Fuel Gas Code, ANSI Z223.1. Where required by
the authority having jurisdiction, the installation must conform
to American Society of Mechanical Engineers Safety Code for
Controls and Safety Devices for Automatically Fired Boilers,
ASME CSD-1. All boilers conform to the latest edition of the
ASME Boiler and Pressure Vessel Code, Section IV. Where
required by the authority having jurisdiction, the installation
must comply with the Canadian Association Code, CAN/CGA­B149.1 and/or local codes.

This appliance meets the safe lighting performance criteria with
the gas manifold and control assembly provided as specified in
the ANSI standards for gas-fired appliances, ANSI Z21.13 and
ANSI Z21.10.3.

5

Ratings

Maximum allowed working pressure is located on the rating plate.

NOTICE

Installation & Service Manual

Copper-fin

I=B=R Rating

Model Number

Note: Change “N” to

“L” for L.P. gas models.

Input
MBH

(Note 4)

Min Max

Gross

Output

MBH

(Note 1)

Net

I=B=R

Ratings

Water,

MBH

(Note 2)

CBN315 158 315 258 224

CBN360 180 360 295 257

CBN399 200 399 328 285

CBN500 250 500 410 357

Other Specifications

Boiler Water

Content
Gallons

Water

Connections

Gas

Connections

Vent

Size

(Note 3)

1.09

2" 3/4" 8"

1.12

2" 1" 9"

1.22

2" 1" 10"

1.30

2" 1" 10"

Notes:

1. The ratings are based on standard test procedures
prescribed by the United States Department of Energy.

2. Net I=B=R ratings are based on net installed radiation of
sufficient quantity for the requirements of the building and
nothing need be added for normal piping and pickup.
Ratings are based on a piping and pickup allowance of 1.15.

3. Copper-fins require special gas venting. Use only the vent
materials and methods specified in the Installation and
Service Manual.

4. The Copper-fin is orificed for operation up to 2000 feet
altitude. The ap pli ance will be derated 4% per 1000 feet
above 2000 feet el e va tion. Consult the factory for
installations above 2000 feet elevation.

5. Ratings have been confirmed by AHRI.

Figure A High Altitude Label Location

UNIT EQUIPPED FOR

HIGH ALTITUDE

UP TO 2000 FT.

6

Ratings

Installation & Service Manual

Notes:

1. Copper-fins require special gas venting. Use only the vent
materials and methods specified in the Installation and
Service Manual.

2. The Copper-fin is orificed for operation up to 2000 feet
altitude. The ap pli ance will be derated 4% per 1000 feet
above 2000 feet el e va tion. Consult the factory for
installations above 2000 feet elevation.

Figure B High Altitude Label Location

UNIT EQUIPPED FOR

HIGH ALTITUDE

UP TO 2000 FT.

Copper-fin Specifications

Model Number

Note: Change “N” to

“L” for L.P. gas models

Input
MBH

Water

Content Gallons

Water Connections Gas Connections

Vent Size

(Note 1)

CWN090 90 .91 2” 1/2” 5”

CWN135 135 .95 2” 1/2” 6”

CWN180 180 .99 2” 3/4” 7”

CWN199 199 1.02 2” 3/4” 7”

CWN225 225 1.02 2” 3/4” 7”

CWN270 270 1.06 2” 3/4” 8”

CWN315

315 1.09 2" 3/4" 8"

CWN360

360 1.12 2" 1" 9"

CWN399

399 1.22 2" 1" 10"

CWN500

500 1.30 2" 1" 10"

Maximum allowed working pressure is located on the rating plate.

NOTICE

7

Installation & Service Manual

The Copper-fin - How it works...

1. Control panel cover

The control panel cover provides access to the thermostat,
ignition module, and transformer.

2. Drain port (not shown)

Location from which the heat exchanger can be drained.

3. Flue outlet

The flue outlet allows the connection of the vent pipe to the unit.

4. Gas connection pipe

The gas pipe connection on this appliance should be connected to
the incoming gas supply for the purpose of delivering gas to the
appliance.

5. Gas valve

The gas valve allows the proper amount of gas to pass into the
burner for combustion.

6. Heat exchanger

The heat exchanger allows system water to flow through specially
designed tubes for maximum heat transfer. The glass lined
headers and copper finned tubing are encased in a jacket that
contains the combustion process.

7. High limit sensor

Device that monitors the outlet water temperature to ensure
safe operation. If the temperature exceeds its setting , it will break
the control circuit, shutting the appliance down.

8. Ignition module (F9 and M9 models only)

The ignition module responds to a call for heat signal to provide
burner operation .

9. Junction box

The junction box contains the connection points for the line
voltage power and the pump.

10. Relief valve

The relief valve is a safety device that ensures the maximum
pressure of the appliance is not exceeded. Water heaters are
supplied with a temperature and pressure relief valve.

11. Terminal strip

The boiler is equipped with a terminal strip on the left side of the
control panel to allow easy connection to contact points on the
unit.

12. Thermostat

The thermostat monitors the water temperature via a temperature
sensor and will initiate a call for heat when the water temperature
drops below the setpoint plus the differential on the thermostat.

13. Temperature gauge (CW models only)

The temperature gauge monitors the inlet temperature of the
water heater as well as the outlet temperature.

14. Transformer

The transformer reduces 120 VAC supply voltage to 24 VAC for the
control circuit.

15. Water inlet

The water inlet is a 2" pipe connection that receives water from the
system and delivers it to the heat exchanger.

16. Water outlet

The water outlet is a 2" pipe connection that supplies water to
the system .

17. Burner (not shown)

The burner is a cylindrical stainless steel tube used to regulate
burner flame.

18. Pilot (not shown)

( F9 and M9 models only)

The pilot is a spark ignition device is used to light a pilot flame
which in turn is used to light the main burners.

( F1 models only)

The pilot uses a standing flame to light the main burner.

19. Sight Glass (not shown)

The sight glass provides a view of the burner surface, burner
flame, and the pilot flame.

20. Temperature and pressure gauge (CB models only)

The temperature and pressure gauge monitors the outlet
temperature of the boiler as well as the system water pressure.

21. Pump (shipped with CW models only)

The pump ensures adequate flow to operate the unit.

22. Pump relay

The pump relay energizes the pump on a call for heat.

23. Temperature sensor

This sensor monitors inlet water temperature. If selected as the
controlling sensor, the appliance will maintain the setpoint at this
sensor.

Installation & Service Manual

8

Models CWN270 Front View

Model CWN399 (inside unit)

Model CWN399 Front View

Model CWN270 (inside unit)

The Copper-fin - How it works...

3

1

10

9

11

5

21

15

16

22

6

12

8

4

14

23

7

13

6

7

13

23

4

22

14

12

8

3

10

1

16

9

21

15

11

5

9

Installation & Service Manual

The Copper-fin - How it works... (continued)

Model CBN500 (inside unit)

Model CBN500 Front View

Models CBN399 (inside unit)

Model CBN399 Front View

3

1

20

10

16

15

11

9

5

6

12

8

14

22

23

4

7

3

1

20

10

16

15

5

11

9

6

12

4

14

8

7

23

22

10

Installation & Service Manual

1 Determine unit location

NOTICE

Clearances from combustible construction
are noted on the appliance rating plate.

Location of unit

1. Locate the appliance so that if water connections should
leak, water damage will not occur. 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. Under no circumstances is the manufacturer to be
held responsible for water damage in connection with
this appliance, or any of its components.

2. The appliance must be installed indoors where it is
protected from exposure to wind, rain and weather.

3. The appliance must be installed so that the ignition
system components are protected from water (dripping,
spraying, rain, etc.,) during appliance operation and
service (circulator replacement, control replacement,
etc.,).

4. Appliances located in a residential garage and in adjacent
spaces that open to the garage and are not part of the
living space of a dwelling unit must be installed so that
all burners and burner ignition devices have a minimum
clearance of not less than 18" (46cm) above the floor.
The appliance must be located or protected so that it is
not subject to physical damage by a moving vehicle.

5. DO NOT install this appliance in any location where
gasoline or flammable vapors are likely to be present.

6. All units have been approved for alcove installation (an
ALCOVE is a closet enclosure without a front door).

7. The appliance must not be installed on carpet.

8. All units have been approved for use on combustible
surfaces.

9. Allow sufficient space for servicing pipe connections,
pump and other auxiliary equipment, as well as the
appliance.

Figure 1-1_Alcove installation, 90,000 - 180,000 Btu/hr

Figure 1-2_Alcove Installation , 225,000 - 500,000 Btu/hr

14 "
TOP

6" REAR

24"

FRONT

24"
LEFT

29"
TOP

6" RIGHT

6"

REAR

24"

FRONT

24"
LEFT

6"

RIGHT

11

Installation & Service Manual

1 Determine boiler location

Figure 1-3_Combustion Air Direct from Outside

Combustion and ventilation air requirements
for conventionally vented appliances

Provisions for combustion and ventilation air must be in
accordance with the latest edition of the National Fuel Gas
Code, ANSI Z223.1, in Canada, the latest edition of CGA
Standard B149 Installation Code for Gas Burning Appliances
and Equipment, or applicable provisions of the local building
codes.

The room where the appliance is installed MUST be provided
with properly sized openings to assure adequate combustion
air and proper ventilation when the appliance is installed with
conventional venting.

1. If air is taken directly from outside the building
with no duct, provide two permanent openings (see
FIG. 1-3):

(a) Combustion air opening, with a minimum free

area of one square inch per 4000 Btu/hr input
(5.5 cm

2

per kW). This opening must be

located within 12" (30 cm) of the floor.

(b) Ventilation air opening, with a minimum free

area of one square inch per 4000 Btu/hr input
(5.5 cm

2

per kW). This opening must be

located within 12" (30 cm) of the ceiling.

Figure 1-4_Combustion Air Through Ducts

2. If combustion and ventilation air is taken from the
outdoors using a duct to deliver the air to the room where
the appliance is installed, each of the two openings should
be sized based on a minimum free area of one square inch
per 2000 Btu/hr (11cm2 per kW) (see FIG. 1-4).

Figure 1-5_Combustion Air from Interior Space

3. If air is taken from another interior space that is adequately

ventilated, each of the two openings specified above should
have a net free area of one square inch for each 1000 Btu/hr
(22cm2 per kW) of input, but not less than 100 square
inches (645cm2) (see FIG. 1-5).

12

1 Determine boiler location

Installation & Service Manual

4. If a single combustion air opening is provided to bring
combustion air in directly from the outdoors, the
opening must be sized based on a minimum free area of
one square inch per 3000 Btu/hr (7 cm

2

per kW). This
opening must be located within 12" (30 cm) of the top of
the enclosure (see FIG. 1-6).

Figure 1-6_Combustion Air from Outside Single Opening

Combustion air require ments are based on the latest edition
of the National Fuel Gas Code, ANSI Z223.1, in Canada refer
to National Standard CAN B149.1. Check all local code
re quire ments for combustion air.

All dimensions are based on net free area in square inch es.
Metal louvers or screens reduce the free area of a combustion
air opening a minimum of approximately 25%. Check with
louver manufacturers for exact net free area of louvers. Where
two openings are pro vid ed, one must be within 12" (30 cm) of
the ceiling and one must be within 12" (30 cm) of the floor of
the room where the appliance is installed. Each opening must
have a net free area as specified in Table 1B (on page 13).
Single openings shall be located with in 12" (30 cm) of the
ceiling.

 CAUTION

Under no circumstances should the room
where the appliance is installed ever be
under a negative pressure. Particular care
should be taken where exhaust fans, attic
fans, clothes dryers, compressors, air
handling units, etc., may take away air from
the appliance.

The combustion air supply must be completely free of any
flammable vapors that may ignite or chemical fumes which may
be corrosive to the appliance. Common corrosive chemical
fumes which must be avoided are fluorocarbons and other
halogenated compounds, most commonly present as
refrigerants or solvents, such as freon, tricholorethylene,
perchlorethylene, chlorine, etc. These chemicals, when burned,
form acids which quickly attack the heat exchanger finned tubes,
headers, flue collectors, and the vent system. The result is
improper combustion and a non-warrantable, premature
appliance failure.

The result is improper combustion and a non-warrantable,
premature appliance failure.

EXHAUST FANS: Any fan or equipment which exhausts air
from the equipment room may deplete the combustion air
supply and/or cause a downdraft in the venting system. Spillage
of flue products from the venting system into an occupied living
space can cause a very hazardous condition that must be
immediately corrected. If a fan is used to supply combustion air
to the equipment room, the installer must make sure that it does
not cause drafts which could lead to nuisance operational
problems with the appliance.

1 Determine boiler location (continued)

13

Installation & Service Manual

TABLE - 1B

MINIMUM RECOMMENDED COMBUSTION

AIR SUPPLY TO EQUIPMENT ROOM

Input

Btu/hr

*Outside Air from

2 Openings Directly from

Outdoors

*Outside Air from

1 Opening Directly

from Outdoors, in

2

*Outside Air from

2 Ducts Delivered from

Outdoors

**Inside Air from

2 Ducts Delivered from

Interior Space

To p

Opening, in

2

Bottom

Opening, in

2

To p

Opening, in

2

Bottom

Opening, in

2

To p

Opening, in

2

Bottom

Opening, in

2

90,000

23

(148 cm

2

)

23

(148 cm

2

)

30

(194 cm

2

)

45

(291 cm

2

)

45

(291 cm

2

)

100

(646 cm

2

)

100

(646 cm

2

)

135,000

34

(220 cm

2

)

34

(220 cm

2

)

45

(291 cm

2

)

68

(439 cm

2

)

68

(439 cm

2

)

135

(871 cm

2

)

135

(871 cm

2

)

180,000

45

(291 cm2)

45

(291 cm2)

60

(388 cm2)

90

(581 cm2)

90

(581 cm2)

180

(1,162 cm2)

180

(1,162 cm2)

199,999

50

(323 cm

2

)

50

(323 cm

2

)

67

(433 cm

2

)

100

(646 cm

2

)

100

(646 cm

2

)

200

(1,291 cm

2

)

200

(1,291 cm

2

)

225,000

57

(368 cm2)

57

(368 cm2)

75

(484 cm2)

113

(730 cm2)

113

(730 cm2)

225

(1,452 cm2)

225

(1,452 cm2)

270,000

68

(439 cm2)

68

(439 cm2)

90

(581 cm2)

135

(871 cm2)

135

(871 cm2)

270

(1,742 cm2)

270

(1,742 cm2)

315,000

79

(510 cm

2

)

79

(510 cm

2

)

105

(678 cm

2

)

158

(1,020 cm

2

)

158

(1,020 cm

2

)

315

(2,033 cm

2

)

315

(2,033 cm

2

)

360,000

90

(581 cm

2

)

90

(581 cm

2

)

120

(775 cm

2

)

180

(1,162 cm

2

)

180

(1,162 cm

2

)

360

(2,323 cm

2

)

360

(2,323 cm

2

)

399,999

100

(646 cm2)

100

(646 cm2)

134

(865 cm2)

200

(1,291 cm2)

200

(1,291 cm2)

400

(2,581 cm2)

400

(2,581 cm2)

500,000

125

(807 cm2)

125

(807 cm2)

167

(1,078 cm2)

250

(1,613 cm2)

250

(1,613 cm2)

500

(3,226 cm2)

500

(3,226 cm2)

*Outside air openings shall directly communicate with the outdoors. When combustion air is drawn from the outside through a
duct, the net free area of each of the two openings must have twice (2 times) the free area required for Outside Air/2 Openings.
The above requirements are for the boiler only; additional gas fired appliances in the equipment room will require an increase in
the net free area to supply adequate combustion air for all appliances.

**Combined interior space must be 50 cubic feet per 1,000 Btu/hr input. Buildings MUST NOT be of *“Tight Construction”.
For buildings of *“Tight Construction”, provide air openings into the building from outside.

*No combustion air openings are needed when the water heater is installed in a space with a volume NO LESS than 50 cubic feet
per 1,000 Btu/hr of all installed gas fired appliances. Buildings MUST NOT be of *“Tight Construction”.

* “Tight Construction” is defined as a building with less than 0.40 ACH (air changes per hour).

Vent installations for connection to gas vents or
chimneys must be in accordance with “Vent ing of
Equipment,” of the latest edition of the Na tion al Fuel Gas
Code, ANSI Z223.1, in Canada, the latest edi tion of CGA
Standard B149 Installation Code for Gas Burning Appliances
and Equipment or applicable pro vi sions of the local building
codes.

Adequate combustion and ventilation air must be
sup plied to the room where the appliance is installed in
accordance with the latest edition of the National Fuel Gas
Code, ANSI Z223.1, in Canada, the latest edition of CGA
Standard B149 Installation Code for Gas Burning Ap pli anc es
and Equipment, or applicable pro vi sions of the local building
codes.

14

Installation & Service Manual

2 Venting

The distance of the vent terminal from adjacent
build ings, windows that open and building open ings MUST
comply with the latest edition of the National Fuel Gas Code,
ANSI Z223.1, in Canada, the latest edition of CGA Standard
B149 In stal la tion Code for Gas Burn ing Appliances and
Equipment.

Vent connection is made directly to the top of the
ap pli ance. This appliance is designed with a built-in draft
diverter. No additional external draft hood is re quired. The
connection from the appliance vent to the common vent or
chimney must be made as direct as possible.

A Conventional Negative Draft
Venting System

The negative draft in a conventional vent in stal la tion must be
within the range of a negative 0.02 to 0.05 inches water column
to ensure proper operation. All draft read ings are made while
the appliance is in stable op er a tion (approximately 2 to 5
minutes).

Multiple appliance installations with combined vent ing or
common venting with other negative draft ap pli anc es require
that each appliance must have draft with in the proper range. If
the draft mea sured above the appliance’s built-in draft diverter
ex ceeds the specified range in a dedicated chimney for a single
appliance installation or in combined venting with other
negative draft appliances, a baro met ric damper must be in -

stalled to control draft.

Figure 2-1_Conventional Negative Draft Vertical Venting

TABLE - 2A

VENT PIPE SIZES

Input Btu/hr Flue Size

90,000 5"

135,000 6"

180,000 7"

199,999 7"

225,000 7"

270,000 8"

315,000 8"

360,000 9"

399,999 10"

500,000 10"

On a conventionally vented, negative draft ap pli ance, the
connection from the vent to the chimney or vent termination on
the outside of the building MUST be made with listed Type “B”
double wall (or equivalent) vent connectors and must be direct
as possible with no reduction in diameter. Use the National Fuel
Gas Code venting tables for dou ble wall vent to properly size all
vent connectors and stacks. The Type “B” vent and accessories,
such as firestop spacers, thim bles, caps, etc., MUST be installed
in accordance with the manufacturer’s list ing. The vent
connector and firestop must provide correct spacing to
combustible surfaces and seal to the vent connector on the upper
and lower sides of each floor or ceiling through which the vent
connector passes.

Any vent materials used must be listed by a na tion al ly
recognized test agency for use as vent ma te ri al.

2 Venting (continued)

15

Installation & Service Manual

Locate appliance as close as possible to a chimney or gas vent.

Avoid long horizontal runs of the vent pipe, 90° el bows,
reductions and restrictions. Horizontal por tions of the
venting system shall be supported to prevent sagging.
Horizontal runs must slope up wards not less than 1/4 inch
per foot (21 mm/m) from the appliance to the vent terminal.
Follow manufacturer’s instructions.

Do not use an existing chimney as a raceway for a flue pipe if
another appliance or fireplace is vented through the chimney.

The weight of the venting system must not rest on the
appliance. Adequate support of the venting sys tem must be
provided in compliance with local codes and other applicable
codes. All connections should be secured with rustproof
sheet metal screws.

Vent connectors serving appliances vented by nat u ral draft
shall not be connected to any portion of a
me chan i cal draft system operating under positive
pres sure. Connection to a positive pressure chim ney may
cause flue products to be discharged into the living space
causing serious health injury.

Common venting systems may be too large when an existing
appliance is removed. At the time of removal of an existing
appliance, the following steps shall be followed with each
appliance remaining connected to the common venting
system placed in operation, while other appliances remaining
con nect ed to the common venting system are not in
operation.

(a) Seal any unused opening 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 other
appliances 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
ex haust 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 draft hood/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
other gas burning ap pli anc es to their previous
conditions of use.

(g) Any improper operation of the common venting

system should be corrected so that the installation
conforms to the latest edition of the Na tion al Fuel Gas
Code, ANSI Z223.1. In Canada, the latest edition of
CGA Standard B149 Installation Code for Gas Burning
Appliances and Equipment. When resizing any
por tion of the common venting system, the common
venting system should be resized to ap proach the
min i mum size as determined using the appropriate
tables in Part 11 in the latest edition of the National
Fuel Gas Code, ANSI Z223.1. In Canada, the latest
edition of CGA Stan dard B149 Installation Code for
Gas Burning Appliances and Equipment.

16

2 Venting

Installation & Service Manual

Vertical Vent Termination Clearances

Figure 2-2_Vent Termination from Peaked Roof 10' or
Less from Ridge

Figure 2-4_Vent Termination from Flat Roof 10' or Less
from Parapet Wall

Figure 2-3_Vent Termination from Peaked Roof More
than 10' from Ridge

Figure 2-5_Vent Termination from Flat Roof More Than
10' from Parapet Wall

The vent terminal should be vertical and exhaust outside the
building at least 2 feet (0.61m) above the high est point of the
roof within a 10 foot (3.05m) radius of the termination. The
vertical termination must be a minimum of 3 feet (0.91m)
above the point of exit.

A vertical terminal less than 10 feet (3.05m) from a parapet
wall must be a minimum of 2 feet (0.61m) higher than the
parapet wall.

The vent cap should have a minimum clearance of 4 feet
(1.22m) horizontally from and in no case above or below,
unless a 4 foot (1.22m) horizontal distance is maintained
from electric meters, gas meters, reg u la tors and relief
equipment.

The venting system shall terminate at least 3 feet (0.9m) above
any forced air inlet within 10 feet (3.05m).

The venting system shall terminate at least 4 feet (1.2m)
below, 4 feet (1.2m) horizontally from, or 1 foot (30cm) above
any door, window or gravity air inlet into any building.

Do not terminate the vent in a window well, stair well, alcove,
courtyard or other recessed area. The vent can not terminate
below grade. The bot tom of the vent terminal shall be located
at least 12 inches (30cm) above grade.

To avoid a blocked vent condition, keep the vent cap clear of
snow, ice, leaves, debris, etc.

Flue gases will form a white plume in winter. Plume could
obstruct window view.

Flue gas condensate can freeze on exterior sur fac es or on the
vent cap. Frozen condensate on the vent cap can result in a
blocked vent condition. Flue gas condensate can cause
discoloration of exterior build ing surfaces. Adjacent brick or
masonry sur fac es should be protected with a rust resistant sheet
metal plate.

NOTICE

Examine the venting system at least once a
year. Check all joints and vent pipe
con nec tions for tightness. Also check for
corrosion or de te ri o ra tion. Immediately
correct any problems ob served in the
venting system.

2' MIN

10' OR LESS

3' MIN

CHIMNEY

RIDGE

10' OR LESS

10' OR LESS

MORE THAN 10'

10'

2' MIN

RIDGE

CHIMNEY

3' MIN

2' MIN

CHIMMEY

WALL OR
PARAPET

2' MIN

3' MIN

CHIMMEY

10' OR MORE

3'

NOTE:
NO HEIGHT ABOVE
PARAPET REQUIRED
WHEN DISTANCE
FROM WALLS OR
PARAPETS IS MORE
THAN 10'.

WALL OR
PARAPET

CHIMNEY

2 Venting (continued)

17

Installation & Service Manual

Masonry Chimney Installation

A masonry chimney must be properly sized for the
installation of a gas fired appliance. Venting of an appliance
into a cold or oversized masonry chimney can result in
op er a tion al and safety problems. Exterior masonry
chim neys, with one or more sides exposed to cold out door
tem per a tures, are more likely to have venting problems. The
temperature of the flue gases from an appliance may not be
able to suf fi cient ly heat the ma son ry structure of the chim ney
to generate proper draft. This will result in condensing of flue
gases, damage the masonry flue/tile, insufficient draft and
possible spill age of flue gases into an occupied living space.
Care ful ly in spect all chimney systems before installation. If
there is any doubt about the sizing or condition of a masonry
chimney, it must be relined with a prop er ly sized and
approved chimney liner system.

Inspection of a Masonry Chimney

A masonry chimney must be carefully inspected to determine
its suitability for the venting of flue gas es. A clay tile lined
chimney must be structurally sound, straight and free of
misaligned tile, gaps between liner sections, missing sections
of liner or any signs of con den sate drainage at the breaching
or clean out. If there is any doubt about the condition of a
masonry chimney, it must be relined. An unlined masonry
chimney must not be used to vent flue gases from this
appliance. An unlined chimney must be relined with an
approved chimney liner system when a new appliance is be ­ing attached to it. Metallic liner systems (Type “B” double
wall or flexible or rigid metallic liners) are recommended.
Consult with local code officials to determine code
requirements or the advisability of using or relining a
masonry chimney.

Sidewall Venting

This appliance is NOT approved for sidewall venting with the
negative draft venting system as shipped from the factory. An
induced draft fan MUST be used if the installation requires that
the flue gases be vented out a sidewall. A properly sized and
in stalled induced draft fan may also be used to vent the flue
gases ver ti cal ly if required by job site conditions. The induced
draft fan must be listed by a nationally recognized test agency,
be properly sized and installed per the rec om men da tions of the
in duced draft fan manufacturer and meet local code
requirements. Use care to ensure that the me chan i cal ly
supplied draft does not exceed the range of a negative 0.02 to

0.05 inches water column to ensure proper operation. If draft
exceeds the spec i fied range, the fan must be adjusted or the
installation of a baro met ric damper in the flue may be required
to prop er ly control draft.

An induced draft fan MUST be interlocked into the appliance’s
control circuit to start when the appliance calls for heat. The
in duced draft fan MUST also be equipped with a prov ing
switch, properly interlocked into the ap pli ance’s con trol circuit
to prove fan operation before the main burn ers are allowed to
fire. A vertical or sidewall vent termination for an induced draft
fan MUST be in stalled per the recommendations of the fan
manufacturer and provide proper clearances from any
combustion or ventilation openings, win dows, doors or other
open ings into the building. All induced draft fan in stal la tions
must comply with local code requirements.

TABLE - 7B

VENT MATERIALS

Kit

Number

Input

Btu / hr

Material

KIT3104

90,000 CPVC Rated

135,000 CPVC Rated

Minimum Vent Length = 12 Equivalent Feet *

(ALL UNITS)

Maximum Vent Length = 25 Equivalent Feet * *

(ALL UNITS)

*Equivalent Feet: 90° Elbow = 5 Feet

45° Elbow = 3 Feet

Figure 2-6_CW135 with Fan Assisted Venting

Fan Assisted Venting

A Power Venter kit is available on models 90,000 - 135,000
Btu/hr, water heaters only.

18

2 Venting

Installation & Service Manual

Automatic Vent Damper

This heating boiler is design certified for use with the automatic
vent damper (FIG. 2-7) part number printed on the boiler’s
rating plate. A vent damper is optional on heating boilers above
360,000 Btu/hr. Automatic vent dampers are not required or
fur nished on potable water heaters. Water heaters with inputs of
360,000 Btu/hr and less may be ordered with the vent damp er as
an option. A vent damper is a useful tool for saving energy when
installed inside the living space where air can cir cu late freely
around the appliance. The vent damper will not save as much,
if any, energy if it is installed in locations such as:

- Unheated garage

- Attic

- Crawlspace

- Mechanical room that is vented outdoors

For installation and maintenance on the vent damper, refer to
the instructions supplied with the vent damper.

Larger input heating boilers and water heaters will have a
jumper plug installed in the ter mi nal block to allow operation
without a damper. Remove the jumper plug from the terminal
block to connect an optional vent damper wire harness (water
heater shown in FIG. 2_8). The jumper plug MUST be in place
if an optional vent damper is not used on water heaters and
larger input heating boilers.

Do not install the vent damper within 6"
(152 mm) of combustible materials.

The damper position indicator must be in a visible
lo ca tion with access for service following in stal la tion. The
damper must be in an open position when appliance main
burners are operating.

The part number for the automatic vent damper required on
this heating boiler is printed on the rating plate. Vent damper
regulations are design certified per the latest edition of ANSI
Z21.66.

Figure 2-7_CB with Vent Damper and Vent Damper
Terminal Block

 WARNING

The vent damper must be installed directly
on the flue outlet located on the top of the
draft hood (see FIG. 2-7). Do not alter the
wire har ness sup plied with the vent damper.
Follow the instructions supplied with the
vent damper.

 CAUTION

An appliance which is shut down or will not
operate may experience freezing due to
con vec tive air flow down the flue pipe
connected to the unit. Proper freeze
protection must be pro vid ed, see Freeze
Pro tec tion in the Startup Section of this
manual.

 DANGER

Install the vent damper to service only the
single ap pli ance for which it is intended. If
improperly installed, a hazardous
condition such as an ex plo sion or carbon
monoxide poisoning could result.

 WARNING

Figure 2-8_CW with Vent Damper

VENT DAMPER

TERMINAL

BLOCK

VENT DAMPER

19

Installation & Service Manual

3 Gas connections

Gas Supply

Verify that the appliance is supplied with the type gas
spec i fied on the rating plate. This appliance is orificed for
operation up to 2000 feet altitude. The ap pli ance will be
derated 4% per 1000 feet above 2000 feet el e va tion. Consult
the factory for installations above 2000 feet elevation. Field
conversions for operation at high altitude must be performed
by certified per son nel only. The appliance will be marked to
indicate suitability for high al ti tude operation.

GAS SUPPLY PRESSURE: Measured at the inlet pres sure tap
located upstream of the combination gas valve(s) see
FIG.’s 3-5 and 3-6, page 23.

TABLE - 3A

GAS SUPPLY PRESSURE

Max. (Inches Water Column)

Natural Gas LP Gas

14 14

Min. (Inches Water Column) *4.5 11

Min. (Inches Water Column) **5.0 11

*Models 90,000 - 360,000 Btu/hr Only

**Models 399,999 - 500,000 Btu/hr Only

Maximum inlet gas pressure must not exceed the val ue
specified. Minimum value listed is for the purposes of input
adjustment.

MANIFOLD PRESSURE: Measured at the pres sure tap on
the downstream side of the com bi na tion gas valve(s) (see
FIG.’s 3-5 and 3-6, page 23). The gas regulator settings for
single stage and two stage operation are factory set to supply
proper manifold pressure for normal operation. To check
manifold pressure, see Manifold Ad just ment Procedure. Do
not increase manifold pressure beyond spec i fied pressure
settings shown below in Table 3B.

TABLE - 3B

MANIFOLD PRESSURE

Input Gas

Btu/hr

Single and Two-Stage Two Stage

Full or High Fire Settings Low Fire Settings

Natural Gas LP Gas Natural Gas LP Gas

90,000 - 180,000 3.5" 10" 0.9" 2.5"

199,999 2.9" 7.5" 0.9" 2.5"

215,000 - 399,999 3.5" 10" 0.9" 2.5"

500,000 3.5"

10"

(two valves)

N/A N/A

Gas Pressure Test

1. The appliance must be disconnected from the gas supply
piping system during any pressure testing of that system at
a test pressure in excess of 1/2 PSIG (3.5kPa).

2. The appliance must be isolated from the gas supply piping
system by closing a manual shutoff valve during any
pressure testing of the gas supply piping system at test
pressures equal to or less than 1/2 PSIG (3.5kPa).

3. The appliance and its gas connection must be leak-tested
before placing it in operation.

Gas Connection

1. Safe operation of the appliance requires properly sized gas
supply piping.

2. Gas pipe size may be larger than appliance gas connection.

3. Installation of a union is suggested for ease of service, see
FIG. 3-1 on page 20.

4. Install a manual main gas shutoff valve, outside of the
appliance gas connection and before the gas valve or
manifold connection, when local codes require.

5. A trap (drip leg) MUST be provided by the installer in

the inlet of the gas connection to the appliance, see
FIG. 3-1 on page 20.

6. The combination gas valve has an integral vent lim it ing
device and does not require venting to atmosphere,
outside the building.

7. Optional gas controls may require routing of bleeds and
vents to the atmosphere, outside the building when
required by local codes.

TABLE - 3C

FITTINGS TO EQUIVALENT STRAIGHT PIPE

Diameter Pipe (inches)

3/4 1 1 1/4 1 1/2 2 3 4 5

Equivalent Length of Straight Pipe (feet)

2 2 3 4 5 10 14 20

TABLE - 3D

GAS CONNECTIONS

Btu/hr

INPUT

Pipe Size

90,000 - 135,000 1/2"

180,000 - 315,000 3/4"

360,000 - 500,000 1

20

3 Gas connections

Installation & Service Manual

TABLE - 3E

MULTIPLE APPLIANCE INSTALLATIONS

GAS PIPING SIZE CHART

Nominal

Iron Pipe

Size

Inches

Length of Pipe in Straight Feet

Maximum
Capacity of Pipe
in Thousands of

Btu/hr per hour

for gas pressures

of 13.5 Inches

Water Column

(0.5 PSIG) or less

and a pressure

drop of 0.5 Inch

Water Column

(Based on NAT

GAS, 1025

Btu/hr per Cubic

Foot of Gas and

0.60 Specific
Gravity)

10 20 30 40 50 60 70 80 90 100 125 150 175 200

3/4 369 256 205 174 155 141 128 121 113 106 95 86 79 74

1 697 477 384 328 292 267 246 226 210 200 179 164 149 138

1 1/4 1,400 974 789 677 595 543 502 472 441 410 369 333 308 287

1 1/2 2,150 1,500 1,210 1,020 923 830 769 707 666 636 564 513 472 441

2 4,100 2,820 2,260 1,950 1,720 1,560 1,440 1,330 1,250 1,180 1,100 974 871 820

2 1/2 6,460 4,460 3,610 3,100 2,720 2,460 2,310 2,100 2,000 1,900 1,700 1,540 1,400 1,300

3 11,200 7,900 6,400 5,400 4,870 4,410 4,000 3,800 3,540 3,300 3,000 2,720 2,500 2,340

4 23,500 16,100 13,100 11,100 10,000 9,000 8,300 7,690 7,380 6,870 6,150 5,640 5,130 4,720

Gas Piping

Figure 3-1_Gas Line Connection

All gas connections must be made with pipe joint
com pound resistant to the action of liquefied pe tro leum and
natural gas. All piping must comply with local codes. Tubing
installations must com ply with ap proved standards and
practices. Reference FIG. 3-1 for a typical installation.

Install Piping to Control

1. The gas line should be a separate line direct
from the meter unless the existing gas line is of sufficient
capacity. Verify pipe size with your gas sup pli er.

2. Use new, properly threaded black iron pipe free from chips.
If tubing is used, make sure the ends are cut squared,
deburred and clean. All tubing bends must be smooth and
without deformation. Avoid flexible gas connections.
Internal diameter of flexible lines may not provide proper
volume of gas.

3. Run pipe or tubing to the gas valve or manifold inlet. If
tubing is used, obtain a tube to pipe coupling to connect
the tubing to the gas valve or man i fold inlet.

4. DO NOT OVER TIGHTEN. Over tightening may result in
damage to the gas valves. Valve distortion or malfunction
may result if the pipe is inserted too deeply into the gas
valve.

5. Apply a moderate amount of good quality pipe compound
(DO NOT use Teflon tape) to pipe only, leaving two end
threads bare.

6. Remove seal over gas valve or manifold inlet.

7. Connect pipe to gas valve or manifold inlet. Use wrench to
square ends of the gas valve (FIG. 3-2).

GAS VALVE

GAS SHUTOFF

TRAP
( DRIP LEG )

UNION

3 Gas connections (continued)

21

Installation & Service Manual

APPLY WRENCH
TO FLANGE ONLY

WHEN FLANGE

IS USED

APPLY WRENCH FROM

BOTTOM OF GAS CONTROL

TO EITHER SHADED AREA

WHEN FLANGE

IS NOT USED

Figure 3-2_Wrench

8. For L.P. gas, consult your L.P. gas supplier for expert
installation.

IMPORTANT

Upon completion of any piping
con nec tions to the gas system, leak test all
gas con nec tions with a soap solution
while system is un der pressure.
Immediately repair any leaks found in the
gas train or related components. Do Not
op er ate an appliance with a leak in the gas
train, valves or related piping.

Gas Manifold Pressure Adjustment
Procedure

Figure 3-3_Manifold Pressure Adjustment

1. Turn the power “OFF” at the main dis con nect switch.

2. Turn gas valve control knob to “PILOT” po si tion on
standing pilot models. Ensure that the stand ing pilot
remains on. If the pilot goes out, follow the “Lighting
Instructions” in Section 6 - Startup for standing pi lot
models to light the pilot. Turn gas valve control knob to
“OFF” po si tion on spark ignition models.

3. Remove the 1/8" hex plug located on the out let side of the
gas valve and install a fitting suitable to connect to a
manometer or magnahelic gauge. See FIG. 3-3. Minimum
range of scale should be up to 5" w.c. for Natural gas
mod els and 10" w.c. for L.P. gas models.

4. The 500,000 Btu/hr model will have two gas valves with a
pressure regulator on each valve. Repeat the following
adjustment pro ce dure to set the manifold pressure on each
gas valve.

5. Remove the pressure regulator adjustment cap screw on
the gas valve. See FIG. 3-3 for location.

6. Turn the power “ON” at the main dis con nect switch.

7. Turn gas valve control knob to “ON” po si tion.

8. Set the thermostat(s) to call for heat.

9. Observe gas regulator pressure when all burn ers are firing.
See Table 3B, Manifold Pressure (page 19) for proper
regulator pressure settings.

10. If adjustment is necessary, turn regulator ad just ment screw
clockwise to raise regulator gas pres sure, counterclockwise
to lower gas pres sure, to proper setting. N

OTE: Adjustment

fitting is plas tic and may require slightly greater turning
force than a metal fitting.

11. Turn the power “OFF” at the main dis con nect switch.

NOTICE

Do not increase regulator pres sure beyond
specified pressure setting.

12. Turn gas valve control knob to “PILOT” po si tion on
standing pilot models. Turn gas valve control knob to
“OFF” position on spark ignition models.

13. Remove fitting from the gas valve and re place the 1/8" hex
plug that was previously removed and tighten.

14. Repeat the adjustment procedure for the sec ond gas valve
on the 500,000 Btu/hr model.

15. Turn the gas valve control knob(s) to “ON” position.

16. Turn the power “ON” at the main dis con nect switch. The
appliance is now ready to op er ate.

If manifold pressure can not be properly adjusted, use the
procedure on page 22 to check gas supply pressure with a
manometer connected to the inlet pressure tap on the gas
control.

INLET

PRESSURE

TAP

MANOMETER

PRESSURE REGULATOR

ADJUSTMENT

(UNDER SCREW CAP)

OUTLET

PRESSURE TAP

PILOT OUTLET

GAS CONTROL KNOB

RED RESET BUTTON

UNION

GAS VALVE