Modine Manufacturing IPT Service Manual

INSTALLATION AND SERVICE MANUAL

low intensity gas-red pressurized infrared heaters

WARNING

1. Improper installation, adjustment,
alteration, service or maintenance can
cause property damage, injury or death,
and could cause exposure to substances
which have been determined by various
state agencies to cause cancer, birth
defects, or other reproductive harm. Read
the installation, operating, and
maintenance instructions thoroughly
before installing or servicing this
equipment.

2. Do not locate ANY gas-fired units in areas
where chlorinated, halogenated, or acidic
vapors are present in the atmosphere.
These substances can cause premature
heat exchanger failure due to corrosion
which can cause property damage, serious
injury or death.

3. For either indoor or outdoor installation.
Not for use in residential dwellings.

CAUTION

As with all infrared equipment, clearances to
combustible materials are critical. Be sure all
units have reflectors installed along the
entire length of the tube, and that they are not
mounted at an angle greater than 45° from
the horizontal plane. In locations used for
storage of combustible materials, signs shall
be clearly posted in the vicinity of the heater
where readily apparent to material handlers
to specify the maximum permissible stacking
height to maintain required clearances from the
heater to the combustibles.

9-511.4

5H0819050000

February, 2019

model IPT

FOR YOUR SAFETY

IF YOU SMELL GAS:

1. Open windows (indoor installation only).

2. Do not touch electrical switches.

3. Extinguish any open flame.

4. Immediately call your gas supplier.

FOR YOUR SAFETY

The use and storage of gasoline or other
flammable vapors and liquids in open
containers in the vicinity of this unit is
hazardous.

IMPORTANT

The use of this manual is specifically intended
for a qualified installation and service agency.
A qualified installation and service agency
must perform all installation and service of
these appliances.

Inspection upon Arrival

1. Inspect unit upon arrival. In case of damage, report it
immediately to transportation company and your local Modine
Sales Representative.

2. Check rating plate on unit to verify that power supply
meets available electric power at the point of installation.

3. Inspect unit upon arrival for conformance with description of
product ordered (including specifications where applicable).

THIS MANUAL IS THE PROPERTY OF THE OWNER.

PLEASE BE SURE TO LEAVE IT WITH THE OWNER WHEN YOU LEAVE THE JOB.

SPECIAL PRECAUTIONS

SPECIAL PRECAUTIONS

THE INSTALLATION AND MAINTENANCE INSTRUCTIONS IN
THIS MANUAL MUST BE FOLLOWED TO PROVIDE SAFE,
EFFICIENT AND TROUBLE-FREE OPERATION. IN ADDITION,
PARTICULAR CARE MUST BE EXERCISED REGARDING
THE SPECIAL PRECAUTIONS LISTED BELOW. FAILURE
TO PROPERLY ADDRESS THESE CRITICAL AREAS COULD
RESULT IN PROPERTY DAMAGE OR LOSS, PERSONAL
INJURY, OR DEATH. THESE INSTRUCTIONS ARE SUBJECT
TO ANY MORE RESTRICTIVE LOCAL OR NATIONAL CODES.

HAZARD INTENSITY LEVELS

1. DANGER: Indicates an imminently hazardous situation
which, if not avoided, WILL result in death or serious injury.

2. WARNING: Indicates a potentially hazardous situation which,
if not avoided, COULD result in death or serious injury.

3. CAUTION: Indicates a potentially hazardous situation which,
if not avoided, MAY result in minor or moderate injury.

4. IMPORTANT: Indicates a situation which, if not avoided,
MAY result in a potential safety concern.

DANGER

Appliances must not be installed where they may be
exposed to a potentially explosive or flammable atmosphere.

WARNING

10. Disconnect power supply before making wiring connections
to prevent electrical shock and equipment damage.

11. All appliances must be wired strictly in accordance with

the wiring diagram furnished with the unit. Any wiring
different from the wiring diagram could result in a hazard
to persons and property.

12. Any original factory wiring that requires replacement

must be replaced with wiring material having a
temperature rating of at least 105°C.

13. Ensure that the supply voltage to the appliance, as

indicated on the serial plate, is not 5% greater than rated
voltage.

14. When servicing or repairing this equipment, use only

factory-approved service replacement parts. A complete
replacement parts list may be obtained by contacting
Modine Manufacturing Company. Refer to the rating
plate on the unit for complete unit model number, serial
number, and company address. Any substitution of parts
or controls not approved by the factory will be at owner’s
risk.

CAUTION

WARNING

1. Do not locate ANY gas-fired units in areas where
chlorinated, halogenated, or acidic vapors are present in
the atmosphere. These substances can cause premature
heat exchanger failure due to corrosion which can cause
property damage, serious injury or death.

2. To prevent risk of fire or improper unit operation, radiant
tube baffle must be properly selected from Table 10.1
according to fuel type, burner input, and tube system length
and it must also be properly assembled and installed.

3. To prevent tube sections from separating during unit
operation, tube clamps must be centered over the joints
of adjoining tube sections and tightened to 50 ft. - lb. and
the clamp fastened to the tubes using (2) self-tapping
screws. Failure to do so may result in separation of tube
sections which could fall and result in death or serious injury.

4. All field gas piping must be pressure/leak tested prior to
operation. Never use an open flame. Use a soap solution
or equivalent for testing.

5. Gas pressure to appliance controls must never exceed
14" W.C. (1/2 psi).

6. Do not join two sections of Type B double wall vent pipe
within the vent system. A compromised pipe joint/liner pipe
may or not be detected, resulting in serious injury or
death.

7. A built-in combustion air blower is provided – additional
external draft hoods (diverters) or power exhausters are
not required or permitted.

8. To reduce the opportunity for condensation, the minimum
sea level input to the appliance, as indicated on the serial
plate, must not be less than 5% below the rated input.

9. A certified flexible connector must be used (local codes
permitting) as a the method of connecting the heaters to
the gas supply to avoid placing stress on the gas supply
line due to the expansion of the low intensity infrared
tubes during operation.

1. As with all infrared equipment, clearances to combustible
materials are critical. Be sure all units have reflectors
installed along the entire length of the tube, and that they
are not mounted at an angle greater than 45° from the
horizontal plane. In locations used for storage of
combustible materials, signs shall be clearly posted in the
vicinity of the heater where readily apparent to material
handlers to specify the maximum permissible stacking
height to maintain required clearances from the heater to
the combustibles.

2. Installation must conform with local building codes or in
the absence of local codes, with Part 7, Venting of
Equipment, or the National Fuel Gas Code, ANSI Z223.1
(NFPA 54) – latest edition. In Canada installation must be
in accordance with CAN/CGA-B149.1 for natural gas
units, and CAN/CGA-B149.2 for propane units.

3. Purging of air from gas lines should be performed as
described in ANSI Z223.1 – latest edition "National Fuel
Gas Code" or in Canada in CAN/CGA-B149 codes.

4. When leak testing the gas supply piping system, the
appliance and its combination gas control must be
isolated during any pressure testing in excess of 14" W.C.
(1/2 psi).

5. The unit should be isolated from the gas supply piping
system by closing its field installed manual shut-off valve.
This manual shut-off valve should be located within 6' of
the heater.

6. Turn off all gas before installing appliance.

7. Ensure that the supply voltage to the appliance, as
indicated on the serial plate, is not 5% less than the rated
voltage.

8. Do not attempt to reuse any mechanical or electrical
controllers which have been wet. Replace defective
controller.

2

9-511.4

SI (METRIC) CONVERSION FACTORS/UNIT LOCATION

Table 3.1 - SI (Metric) Conversion Factors

IMPORTANT

1. Approval requirements for infrared heaters specify that
the suspended type heaters shall be installed in
accordance with certain sections of the National Fire
Codes published by the National Fire Protection
Association and various ANSI standards. SOME of the
requirements are listed below.

Aircraft Hangars: Approval requirements are contained

in the current edition of ANSI/NFPA 409 (or in
accordance with the enforcing authority for Canada).

Public Garages: Approval requirements are contained in

the current edition of NFPA 88B (CAN/CGA B149 for
Canada).

Parking Structures: Approval requirements are

contained in the current edition of NFPA 88A.

General: All installations must be in accordance with the

current edition of ANSI Z-223.1 (NFPA 54) National Fuel
Gas Code and the current edition of the National Electric
Code, ANSI/NFPA 70. For Canada, installations must
conform with local building codes, or in the absence of
local codes, in accordance with the current edition of
CAN/CGA B149 and the Canadian Electric Code, C22.1.

2. Start-up and adjustment procedures should be performed
by a qualified service agency.

3. To check most of the Possible Remedies in the
troubleshooting guide listed in Table 23.1, refer to the
applicable sections of the manual.

To Convert Multiply By To Obtain

"W.C. 0.249 kPa
°F (°F-32) x 5/9 °C
Btu 1.06 kJ
Btu/ft3 37.3 kJ/m
Btu/hr 0.000293 kW
CFH (ft3/hr) 0.000472 m3/min
CFH (ft3/hr) 0.00000787 m3/s
CFM (ft3/min) 0.0283 m3/min
CFM (ft3/min) 0.000472 m3/s

UNIT LOCATION

Appliances must not be installed where they may be
exposed to a potentially explosive or flammable atmosphere.

Do not locate ANY gas-fired units in areas where chlorinated,
halogenated, or acidic vapors are present in the atmosphere.
These substances can cause premature heat exchanger
failure due to corrosion which can cause property damage,
serious injury or death.

To Convert Multiply By To Obtain

feet 0.305 m
Gal/Hr. 0.00379 m3/hr
Gal/Hr. 3.79 l/hr

3

gallons 3.79 l
Horsepower 746 W
inches 25.4 mm
pound 0.454 kg
psig 6.89 kPa
psig 27.7 "W.C.

DANGER

WARNING

Table of Contents

General Information/Installation Codes ...................1

Inspection upon Arrival ................................1

Special Precautions ..................................2

SI (Metric) Conversion Factors .........................3

Unit Location........................................4

Location Recommendations ........................4

Combustion Air Requirements ..........................4

Ventilation Air Requirements ........................4

Clearances to Combustibles ........................4

Installation .........................................5

Pre-Installation Notes .............................5

Removal of Burner Side Access Panels ...............5

Rotation of Gas Valve .............................5

Straight Tube Components .........................6

U-Tube Components..............................7

Unit Mounting – Tube System.......................8

 UnitMounting–TurbulatorBafe ...................10

Unit Mounting – Burner ...........................10

 UnitMounting–Reector .........................11

Additional Recommendations for Outdoor Installation ...11

Venting .......................................12

Gas Connections................................15

High-Altitude Accessory Kit ........................16

Electrical Connections............................18

Start-Up Procedure..................................19

Main Burner Adjustment ..........................19

Primary Air Shutter(Propane Only) ..................19

Control Operating Sequence ......................19

Dimensional Data ...................................20

Performance.......................................21

Maintenance.......................................22

Service & Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Replacement Parts Ordering ..........................24

Model Number Designations ..........................24

Serial Number Designations...........................24

Wiring Diagram..................................25,26

Warranty..........................................28

9-511.4

CAUTION

As with all infrared equipment, clearances to combustible
materials are critical. Be sure all units have reflectors
installed along the entire length of the tube, and that they are
not mounted at an angle greater than 45° from the horizontal
plane. In locations used for storage of combustible materials,
signs, shall be clearly posted in the vicinity of the heater
where readily apparent to material handlers to specify the
maximum permissible stacking height to maintain required
clearances from the heater to the combustibles.

IMPORTANT

Approval requirements for infrared heaters specify that the
suspended type heaters shall be installed in accordance
with certain sections of the National Fire Codes published
by the National Fire Protection Association and various
ANSI standards. SOME of the requirements are listed
below.

Aircraft Hangars: Approval requirements are contained in
the current edition of ANSI/NFPA 409 (or in accordance with
the enforcing authority for Canada).

Public Garages: Approval requirements are contained in
the current edition of NFPA 88B (CAN/CGA B149 for
Canada).

Parking Structures: Approval requirements are contained
in the current edition of NFPA 88A.

General: All installations must be in accordance with the
current edition of ANSI Z-223.1 (NFPA 54) National Fuel
Gas Code and the current edition of the National Electric
Code, ANSI/NFPA 70. For Canada, installations must
conform with local building codes, or in the absence of local
codes, in accordance with the current edition of CAN/CGA
B149 and the Canadian Electric Code, C22.1.

3

UNIT LOCATION /AIR REQUIREMENTS

"B"

"C"

"A"

0° MOUNTING ANGLE

"B"

"C"

"C"

CHAIN LOCATION

45° MOUNTING ANGLE

(MAXIMUM)

"A"

Location Recommendations

1. When locating the heater, consider the general space and
heating requirements and availability of gas and electrical
supply.

2. Be sure the structural support and chain at the unit location is
adequate to support the weight of the unit.

3. Be sure that the minimum clearances to combustible
materials and are maintained. The minimum clearances to
combustibles are shown in Table 4.1, and Figures 4.1 and

4.2, as well as affixed to the burner Model Identification plate.

4. Maintain a recommended minimum of 18" clearance from the
access side of the burner box and also on the combustion air
inlet end of the burner box.

5. Mounting height (measured from the bottom of unit) at which
heaters are installed is important to maintain proper occupant
comfort levels. Please refer to mounting height information in
Table 21.1.

6. Do not locate units in areas where chlorinated, halogenated,
or acid vapors are present in the atmosphere.

7. Unit gas control can be field configured for right or left access,
depending on unit location. See general instructions for
"Rotation of Gas Control" on page 5.

Combustion Air Requirements

Units installed in tightly sealed buildings or confined spaces
must be provided with two permanent openings, one near the
top of the confined space and one near the bottom. Each
opening should have a free area of not less than one square
inch per 1,000 BTU per hour of the total input rating off all units
in the enclosure, freely communicating with interior areas
having, in turn adequate infiltration from the outside.

For further details on supplying combustion air to a confined
(tightly sealed) space or unconfined space, see the National
Fuel Gas Code ANSI Z223.1 of CAN/CGA B149.1 or .2
Installation Code, latest edition.

An accessory combustion air intake collar can be used to bring
outside combustion air to the unit using 4" pipe. Refer to the
venting section "Utilizing Outside Combustion Air" on page 14
for details on pipe length and location.

Clearance to Combustibles

Ensure that:

1. Clearances to combustibles (as shown on the Model
Identification plate and in Table 4.1) are maintained. These
Clearances also apply to vehicles parked below the heater.

2. Adequate clearances to sprinkler heads are maintained. As a
guideline, certified minimum distance to combustible material
is based on the combustible material surface not exceeding

90˚Faboveambient(160˚Ftypical).

3. The stated clearance to combustibles represents a surface
temperature of 90°F (50°C) above room temperature.
Building materials with a low heat tolerance (such as plastics,
vinyl siding, canvas, tri-ply, etc.) may be subject to
degradation at lower temperatures. It is the installer's
responsibility to assure that adjacent materials are protected
from degradation.

Storage of Combustible Materials

In locations used for storage of combustible materials, signs
shall be clearly posted in the vicinity of the heater where readily
apparent to material handlers to specify the maximum
permissible stacking height to maintain required clearances from

the heater to the combustibles. See Figure 4.3.

Table 4.1 - Combustible Material Clearances (inches) ➀

Combustible Material Clearances (inches)

Input MBH “A” ➀ “B” “C”

50/60 9 54 20

75/100/125 9 76 24

150/175/200 12 106 38

➀ Clearance to each end and above the U-Tube is 12 inches.

Refer to Figures 4.1 and 4.2.

Figure 4.1 - Combustible Material Clearances ­Straight Tube

CHAIN LOCATION

"A"

"C"

"B"

0° MOUNTING ANGLE

"A"

"C"

"C"

"B"

45° MOUNTING ANGLE

(MAXIMUM)

Figure 4.2 - Combustible Material Clearances -
U-Tube

CHAIN LOCATION

"A"

"C"

CHAIN LOCATION

"A"

"B"

"U" TUBE

0° MOUNTING ANGLE

"B"

"A"

"C"

"C"

"B"

"B"

"U" TUBE

45° MOUNTING ANGLE

(MAXIMUM)

12"

Figure 4.3 - Stacking Height

Minimum Clearance to
Combustible Materials

Unit Heater

Mounting

Height

Stacking

Height

4

9-511.4

INSTALLATION

Unit Mounting – Pre-Installation Notes

WARNING

1. To prevent risk of fire or improper unit operation, radiant
tube baffle must be properly selected from Table 10.1
according to fuel type, burner input, and tube system
length and it must also be properly assembled and installed.

2. To prevent tube sections from separating during unit
operation, tube clamps must be centered over the joints
of adjoining tube sections and tightened to 50 ft. - lb. and
the clamp fastened to the tubes using (2) self-tapping
screws. Failure to do so may result in separation of tube
sections which could fall and result in death or serious injury.

1. Be sure the method of unit suspension is adequate to support
the weight of the burner and tube system (see Tables 18.1
and 18.2 for system weights).

2. Combustible material and service clearances as specified in
Table 4.1 and Figures 4.1 through 4.3 must be strictly
maintained.

3. Maintain a recommended minimum of 18" clearance from the
access side of the burner box and also on the combustion air
inlet end of the burner box.

4. Before installing, review the components to be installed
against Figure 6.1 and Table 6.1 for straight tube systems or
Figure 7.1 and Table 7.1 for U-Tube systems. Ensure that all
parts are identified and available before proceeding with
installation of the unit.

5. It is recommended that the uninstalled system components
be arranged on the floor, where possible, to match the
intended layout. This can help ensure the layout matches the
intended design.

6. The standard gas control access is on the left side when
looking at the back end of the burner (combustion air inlet
end). If the intended installation requires access from the
opposite side, please follow the instructions in the section
titled "Rotation of Gas Control" prior to burner installation.

7. For proper operation, the burner and tube system must be
installed in a level horizontal position. Use a spirit level during
installation to ensure that the unit is suspended level.

8. Under no circumstances should the gas supply line or the
electrical supply line to the heater provide any assistance in
the suspension of the heater. Do not locate any gas or
electric service line directly above or below the heater.

Removal of Burner Side Access Panels

Each of the two side access panels are held in place by two (2)
screws, as shown in Figure 5.1. Once the screws are removed,
the panels slide down, where they can either hang on the
hooks shown in Figure 22.1 or be removed completely during
service or maintenance. The unit is designed to operate without
these panels in place so that adjustments of the controls can
be made. The panels must be returned to the unit once
installation is complete.

Figure 5.1 - Side Access Panels

Rotation of Gas Control

WARNING

1. All field gas piping must be pressure/leak tested prior to
operation. Never use an open flame. Use a soap solution
or equivalent for testing.

2. Gas pressure to appliance controls must never exceed

14" W.C. (1/2 psi).

This section is only required if opposite side gas control access
is required. The standard access is on the left side when looking
at the back of the burner box (combustion air inlet end).

In order to install the heater so that the gas valve's controls can
be accessed from the opposite side of the burner box, the valve
may be rotated 180° by following the procedure below.

1. Remove burner side access panels as described in the
previous section.

2. Unplug all wires from the valve.

3. Using two wrenches, loosen the factory-supplied union in
the burner box and remove the gas valve. Do not apply
the wrenches directly to either the gas valve or the
gas manifold.

4. Remove the plug from the factory-supplied "tee" fitting and
screw it into the opposite leg of the tee. Be sure to properly
seal the threads of this connection.

5. Seat the gas valve onto the factory-supplied union, so that
the valve faces the opposite side of the burner box.
Tighten the union using two wrenches, without applying
them directly to either the gas valve or the gas manifold.

6. Plug-in all wires removed from the valve in step 2.

7. The gas piping/fitting connections must be pressure/leak
tested as outlined in the section titled "Gas Connections"
on page 15.

8. Replace the burner side access panels.

Remove Screws (2)

Side Access
Panel

9-511.4

5

INSTALLATION

Figure 6.1 - Straight Tube System Components

Ref # Part Description

1 Burner
2 Burner Support Bracket (Qty. 4)
3 Tube Clamp

 4 Tube&ReectorHangerw/ReinforcingBar

5 Radiant Tube

 6 Tube&ReectorHanger

 7 Reector

 8 ReectorEndCap

 9 TurbulatorBafe

Table 6.1 - Straight Tube System Component List

Tube Single-Tube Single-Tube Stocking Kit
Length Available Burner 10' 10' Hangers with Hangers Tube Reector Turbulator Option Requires the

(ft.) Input MBH Tubes Reectors Reinforcing Bar (regular) Clamps End Cap Bafe Sections Following Tube Kits ➁:

20 50, 60, 75 2 2 2 1 3 2 4 A
30 50, 60, 75, 100 3 3 2 2 4 2 4 E
40 60, 75, 100, 125 4 4 2 3 5 ➀ 2 4 A + D
50 100, 125 5 5 2 4 6 ➀ 2 4 E + D

50

150, 175, 200 5 ➀ 5 2 4 6 ➀ 2 4 B + C
60 125 - 1-Stage Only 6 6 2 5 7 ➀ 2 4 A + D + D

60

60 150, 175, 200 6 ➀ 6 2 5 7 ➀ 2 4 B + D
70 175, 200 7 ➀ 7 2 6 8 ➀ 2 4 B + E

➀ Tube systems for input ratings of 150MBH and higher utilize a 409 Aluminized Stainless Steel First tube section with stainless steel tube clamps.
➁ Tube systems can be ordered as either Modular (complete system) or Stocking Kits (combination of kits to form complete system).

6

9-511.4

INSTALLATION

Figure 7.1 - U-Tube System Components

Ref # Part Description

1 Burner
2 Burner Support Bracket (Qty. 4)
3 Tube Clamp

 4 DoubleTube&ReectorHangerw/ReinforcingBar

5 Radiant Tube

 6 DoubleTube&ReectorHanger

7 U-Tube

 8 Reector

 9 ReectorEndCap

 10 TurbulatorBafe

Table 7.1 - U-Tube System Component List

Tube Double-Tube Double-Tube Turbulator Stocking Kit

Length Available Burner 5' 10' 10' Hangers with Hangers Tube Reector Bafe Option Requires the
(ft.) Input MBH Tubes Tubes Reectors Reinforcing Bar (regular) Clamps End Cap U-Tube Sections ➂ Following Tube Kits ➁

20 50, 60, 75 - 2 2 2 - 4 4 1 4 A + U-Tube
30 50, 60, 75, 100 2 2 4 2 1 6 4 1 4 N/A
40 60, 75, 100, 125 - 4 4 2 1 6 4 1 4 A + D + U-Tube
50 100, 125, 150, 175, 200 2 4 ➀ 6 2 2 8 ➀ 4 1 4 N/A
60 125 - 1-Stage Only - 6 6 2 2 8 4 1 4 A + D + D + U-Tube
60 150, 175, 200 - 6 ➀ 6 2 2 8 ➀ 4 1 4 B + D + U-Tube
70 175, 200 2 6 ➀ 8 2 3 10 ➀ 4 1 4 N/A

➀ Tube systems for input ratings of 150MBH and higher utilize a 409 Aluminized Stainless Steel First tube section with stainless steel tube clamps.
➁ Tube systems can be ordered as either Modular (complete system) or Stocking Kits (combination of kits to form complete system).
➂ Forinstallationswhere4bafesareneedonstraighttubesetups,U-tubeinstallationswillonlyrequire3bafes.

9-511.4

7

INSTALLATION

Unit Mounting – Tube System

WARNING

To prevent tube sections from separating during unit
operation, tube clamps must be centered over the joints of
adjoining tube sections and tightened to 50 ft. - lb. and the
clamp fastened to the tubes using (2) self-tapping screws.
Failure to do so may result in separation of tube sections
which could fall and result in death or serious injury.

For steps 1-8 of this section, please refer to Figures 8.1 and 9.1

1. Locate and install tube and reflector system hanging chains
(200 lb. minimum working load) as shown, following spacing
indicated in Table 8.1 or 9.1.

2. Fasten tube and reflector hangers to the hanging chains
installed in the previous step using ¼" diameter S-Hooks (70
lb. minimum working load). The hangers must be positioned
so that the tube system to be installed will be in the horizontal
plane and level. Refer to Figures 8.1 and 9.1 for chain
location on tube systems mounted at a 45° angle. Also note
that the first and last hangers are to be the type with
reinforcing bar. Do not close ends until the tube system
installed in subsequent steps is confirmed to be level.

3. Identify the first burner tube and first and second tube clamps
as follows:

Figure 8.1 - Straight Tube System Suspension

All chains to hang from
overhead structure designed
to support system weight.

• For units under 150,000 Btu/hr, all tubes and clamps
are the same.

• For units 150,000 Btu/hr and over, the first tube is
shinier than the other tubes and is stenciled with the
words “First Tube”. The first two tube clamps have a
shiny, mirror-like appearance.

4. Loosely slide the second tube clamp approximately 6" past

the swaged end (see Figure 8.2 for identification of tube ends).

5. Starting from the end of the tube system where the burner will

be installed (done in later steps), slide the first burner tube
through the first and second tube hangers. The non-swaged
end is to go through the first tube hanger and the swaged end
is to go through the second tube hanger. Position the tube so
the welded seam is directed toward the floor.

6. Loosely slide the next tube clamp over the swaged end of the

next tube and slide the non-swaged end over the swaged end
of the preceding tube, ensuring that the welded seam on the
tube is directed toward the floor. The other end is to be
inserted through the following tube hanger.

7. Center the tube clamp on the preceding tube over the joint of

the two tubes as shown in Figures 8.1 or 9.1 and tighten the
tube clamp bolts to 50 ft.-lb. Secure the tube clamp to both
tubes using (2) self-tapping sheet metal screws.

8. Repeat steps 6 and 7 until all tube sections are installed.

9. Verify that the tube system is level. If the tube is not level,

adjust the position of the hanger on the hanging chain. Once
level, crimp the ends of the S-hooks on the hangers closed.

Ref # Part Description
1 Burner (Installed In Later Steps)

 2 TurbulatorBafe

3 Chain & “S” Hooks
4 Radiant Tube

 5 Tube&ReectorHangerw/ReinforcingBar

6 Tube Clamp
7 Self-Tapping Sheet Metal Screws

 8 Tube&ReectorHanger

TUBE SYSTEM

LENGTH

Table 8.1 -
Straight Tube Chain Spacing

Tube System Number of Minimum "A" "B" "C"
Length (ft) Chains Chain Length ➀ ➁ ➂

20 3 18"

30 4 18"
40 5 18"
50 6 18"
60 7 24"

70 8 24"

➀"A"Dimensionisspacingfromthetubesystemendstotherstandlasthangers.
➁ "B" Dimension is spacing between hangers for tubes between "C" dimensions.
➂"C"Dimensionisspacingbetweenthersttwohangersandthelast2hangers.

Chain to Chain

Spacing Dimensions

N/A

6"

9' 8"

9' 4"

8

Figure 8.2 - Tube Ends (Dimensions in inches)

9-511.4

INSTALLATION

Figure 9.1 - U-Tube System Suspension

Ref # Part Description

1 Burner (installed In later steps)
2 Turbulator Baffle
3 Chain & “S” Hooks
4 Radiant Tube
5 DBL Tube & Reflector Hanger w/ Reinforcing Bar
6 Tube Clamp
7 Double Tube & Reflector Hanger
8 U-Tube
9 Self-Tapping Sheet Metal Screws

Table 9.1 - U-Tube Chain Spacing

Tube System

Length (ft)

20 4
30 6
40 6 4' 4"
50 8

60 8 4' 4"

70 10 4' 4"

➀ “A” Dimension is spacing from the tube system ends to the first hanger and from the U-tube ends to the last hanger.
➁ “B” Dimension is spacing between first and second hangers away from burner.
➂ “C” Dimension is spacing between hangers for tubes between “B” and “D” dimensions.
➃ “D” Dimension is spacing between first and second hangers away from U-tube.

Number of

Chains

Maximum

Chain

Length

18" 6"

"A"

Dimension ①

Espacement des chaînes

"B"

Dimension ②

N/A

9' 4"

"C"

Dimension ③

N/A

9' 8"

"D"

Dimension ④

Sans objet

4' 4"

4' 4"

9-511.4

9

INSTALLATION

Unit Mounting – Turbulator Baffle

WARNING

To prevent risk of fire or improper unit operation, radiant
tube baffle must be properly selected from Table 10.1
according to fuel type, burner input, and tube system length
and it must also be properly assembled and installed.

1. The last section of radiant tube is to include a turbulator baffle
assembly. Determine the quantity of baffle sections to be
installed based on the burner rating and tube system length,
per Table10.1. Discard any baffle sections that will not be
required for the assembly.

Table 10.1 - Turbulator Baffle Assembly Section Qty.
Determination

Bafe Quantity

Input MBH

20 30 40 50 60 70

NG 2 2 - - - -

50

60

75

100

125

150

175

200

* Max. tube length on 125MBH 2-Stage units is 50'
* Note - Tube lengths shown are for units installed at elevations of 0-2001'.
Allowable tube lengths may differ upon elevation changes.
* Note - Forinstallationswhere4bafesareneedon straighttubesetups, 
U-tubeinstallationswillonlyrequire3bafes.

2. Assemble the turbulator baffle assembly by mating the

LP 1 1 - - - -

NG 3 1 0 - - -

LP 3 1 0 - - -

NG 4 2 2 - - -

LP 4 2 - - - -

NG - 4 3 2 - -

LP - 4 3 - - -

NG - - 3 2 2 -

LP - - 4 3 1 -

NG - - - 3 2 -

LP - - - 3 2 -

NG - - - 3 2 2

LP - - - 3 2 0

NG - - - 4 2 0

LP - - - 4 2 0

sections determined in the previous step as shown in
Figure 10.1.

Tube Length (ft)

3. Insert the completed turbulator baffle assembly into the last
radiant tube, flush with the end as shown in Figure 10.2.

Figure 10.2 - Insertion of Turbulator Baffle Assembly

Reflector

Last Tube

Baffle

Unit Mounting – Burner

1. Install four burner support brackets as shown in Figure 10.3
with the bolts supplied.

Figure 10.3 - Burner Support Bracket Installation

2. The burner must be suspended with four chains (200 lb.
minimum working load) to allow for system expansion and
contraction during unit operation, as shown in Figure 10.4.
Note that for U-tube systems mounted at a 45° angle, the
exiting side of the tube system is 12" higher than the burner
(see Figure 4.2). Locate and mount burner to ensure that
Clearance to Combustibles are maintained (refer to
"Clearance to Combustibles" on page 4).

Figure 10.4 - Burner Suspension

Figure 10.1 - Assembly of Turbulator Baffle Assembly

Tabs

Slots

10

9-511.4

INSTALLATION

Unit Mounting – Radiant Reflector

CAUTION

As with all infrared equipment, clearances to combustible
materials are critical. Be sure all units have reflectors
installed along the entire length of the tube, and that they are
not mounted at an angle greater than 45° from the horizontal
plane. In locations used for storage of combustible materials,
signs, shall be clearly posted in the vicinity of the heater
where readily apparent to material handlers to specify the
maximum permissible stacking height to maintain required
clearances from the heater to the combustibles.

For steps 1-7, refer to Figure 11.1.

1. The entire radiant tube length must have radiant reflector
installed. The only exception is that on U-tube systems, a
reflector is not installed over the U-tube.

2. Remove any protective plastic covering the reflectors.

3. Starting from the burner, slide a reflector through the tube and
reflector hangers and position the reflector so that it is
centered over the tube. The end closest to the burner should
be 6" from the first tube and reflector hanger.

Figure 11.1 - Installation of the Radiant Reflectors

4. Slide the next reflector through the tube and reflector hangers
and center over the next tube. The reflector should overlap
the previous reflector by 4". Repeat until all reflectors are
installed (alternating top and bottom overlaps).

5. Starting from the burner end and working toward the vent end
of the tube system, overlapping reflector joints are to be either
secured or remain unsecured as follows:

• Every odd numbered reflector to even numbered

reflector joint (reflectors 1 to 2, 3 to 4, etc.) is to be
secured with self-tapping sheet metal screws.

• Every even numbered reflector to odd numbered

reflector joint (reflectors 2 to 3, 4 to 5, etc.) is to remain
unsecured to allow for expansion and contraction during
operation.

6. Reflector end caps are to be fastened to both ends of the
reflector system using sheet metal screws.

Additional Recommendations for Outdoor Installation

Complies with Canadian Standard CAN1-2.21

When utilized in an outdoor installation or in aircraft hangars, the
following is required:

1. A screened combustion air intake cap.

2. All electrical connections must be water tight and suitable for
outdoor use.

Ref # Part Description

1 Burner
2 Chain & “S” Hooks
3 Radiant Tube

 4 Tube&ReectorHanger

 5 Reector

9-511.4

11

INSTALLATION

Venting

WARNING

1. A built-in combustion air blower is provided – additional
external draft hoods (diverters) or power exhausters are
not required or permitted.

CAUTION

Installation must conform with local building codes or in the
absence of local codes, with Part 7, Venting of Equipment, or
the National Fuel Gas Code, ANSI Z223.1 (NFPA 54) – latest
edition. In Canada installation must be in accordance with
CAN/CGA-B149.1 for natural gas units, and CAN/
CGA-B149.2 for propane units.

General Venting Instructions

The vent pipe may be installed in either a vertical or horizontal
method. Certified vent pipe lengths are as follows:

Table 12.1 - Maximum Vent Length

Input MBH

50, 60, 75, 100

125 30' 30'

150, 175, 200 40' 30'

Min Vent

Lenght (ft.)

5'

Maximum Vent Length (ft.)

1-Stage 2-Stage

20' 20'

Figure 12.2 - Vertical Venting

2' Min.

Approved cap

1' Min.*

See Figure 12.2

Drip Leg

Downward slope 1/4" towards drip leg.

* Size according to expected snow depth.

Figure 12.3 - Construction through Combustible Roof

1. All systems are considered a Category III appliance and the
vent system must be approved for Category III application in
accordance with UL1738 or ULCS636.

2. Use either a certified Category III vent system with a
maximum flue temperature of up to 550°F, or single wall vent
pipe with all joints (fastened with 3 corrosion resistant sheet
metal screws) and seams sealed with a 550°F or greater
sealant. Follow the vent manufacturers instructions for
clearance to combustibles.

3. Refer to the National Fuel Gas Code for the minimum

material thickness and composition of the vent material.

4. If single wall vent systems are used, Type B vent can be used

to terminate the vent system. The Type B double wall vent
must be one continuous section. Under no circumstances
should two sections of double wall vent pipe be joined
together within one vent system due to the inability to verify
complete seal at inner pipes.

5. All seams and joints must be inspected to ensure gas
tightness after installation. Vent system (connections, joints,
and seems) must be leak checked using a soap solution

6. Models 50-75 use 3" venting. Models 100-200 use 4". For

models 50-75, a 4" to 3" reducer must be used to connect the
last tube section to the 3" vent pipe. It is recommended that
vent pipes be fitted with a tee with a drip leg and a clean out
cap to prevent any moisture in the vent pipe from entering the
unit. The drip leg should be inspected and cleaned out
periodically during the heating season See figure 13.1 & 13.3.

7. The National Fuel Gas Code requires a minimum clearance

of 6 inches from combustible materials for single wall vent
pipe. The minimum distance from combustible materials is
based on the combustible material surface not exceeding
160°F. Clearance from the vent pipe (or the top of the unit)
may be required to be greater than 6 inches if heat damage
other than fire (such as material distortion or discoloration)
could result.

8. Avoid venting through unheated space when possible. When
single wall pipe does pass through an unheated space, insulate
runs greater than 5' to minimize condensation. Inspect for
leakage prior to insulating and use insulation that is
noncombustible with a rating of not less than 550°F. Install a
tee fitting at the low point of the vent system and provide a drip
leg with a clean out cap as shown in Figure 12.2. The drip leg
should be cleaned annually.

9. Where the vent passes through a combustible wall or floor or
ceiling, a listed metal thimble 4" greater than the vent
diameter is necessary. If there are six feet or more of vertical
vent pipe in the open space between the unit heater and
where the vent pipe passes through the floor or roof, the
thimble need only be 2" greater than the diameter of the vent
pipe. If a thimble is not used, all combustible material must be
cut away to provide a 6 inch clearance. Any material used to
close an opening must be noncombustible. Vent pipes must
be adequately supported and sealed with a 550°F or greater
sealant.

10. The vent termial must be Modine part number:

- 5H0722850005 (item code 27865) 3" vent pipe

- 5H0722850001 (item code 27866) 4" vent pipe

11. Do NOT vent this appliance into a masonry chimney.

12. Do NOT use dampers or other devices in the vent pipes.

13. Do NOT use PVC pipe.

14. Precautions must be taken to prevent degradation of

building materials by flue products.

15. The top of the vertical stack should extend at least 2' above

any portion of a building within a horizontal distance of 2'.

16. For pitched roof vertical venting, refer to Figure 13.1 and

Table 13.1 for the vertical distance that the cap must extend
above the pitched roof.

17. Common venting is not allowed for Category III appliances.

12

9-511.4

INSTALLATION

A

Listed thimble
to maintain
clearances as
specified by
listed thimble
manufacturer

Vent Pipe

vent terminal

Figure 13.1 - Vertical Venting through Sloped Roof

pproved Cap

Roof Pitch

x

is x/12

H

Drip Leg

Downward slope 1/4" towards drip leg.

12"

See Figure 12.2

Table 13.1 - Minimum Height from Roof to Lowest
Discharge Opening

Rise X (inches) Roof Pitch

0-6 Flat to 6/12 1
6-7 6/12 to 7/12 1.25
7-8 7/12 to 8/12 1.50
8-9 8/12 to 9/12 2

9-10 9/12 to 10/12 2.50
10-11 10/12 to 11/12 3.25
11-12 11/12 to 12/12 4
12-14 12/12 to 14/12 5
14-16 14/12 to 16/12 6
16-18 16/12 to 18/12 7
18-20 18/12 to 20/12 7.50
20-21 20/12 to 21/12 8

* Size according to expected snow depth.

MIn. Height (ft)*

Additional Requirements for Horizontal Venting

1. All horizontal termial must be Modine part number:

- 5H0722850005 (item code 27865) 3" vent pipe

- 5H0722850001 (item code 27866) 4" vent pipe
In the United States, the vent cap must be 24" from wall,
while in Canada, a distance of 48" from the wall is required.

2. When horizontal vents pass through a combustible wall (up to
8 inches thick), use a thimble with 2" clearances to the vent
and insulate between thimble and vent. The vent passage
may also be constructed and insulated as shown in Figure

13.2. Where horizontal vents pass through a non-combustible
wall, no clearances to the wall are required.

3. The vent system shall terminate at least 3' above any forced
air inlet (except direct vent units) located within 10', and at
least 4' below, 4' horizontally from, or 1' above any door,
window or gravity air inlet into any building. The bottom of the
vent terminal shall be located above the snow line or at least
1' above grade; whichever is greater. When located adjacent
to public walkways the vent system shall terminate not less
than 7' above grade.

4. Vent must extend beyond any combustible overhang of the
building.

5. The vent system shall not terminate over public walkways,
building entrances, or where condensate or vapor could
cause a nuisance or hazard or could be detrimental to the
operation of regulators, relief openings, or other equipment.

6. Precautions must be taken to prevent degradation of building
materials by flue products.

7. When vented horizontally, maintain a 1/4" per foot rise away
from the heater. Place a drain tee and clean out near the vent
connector (see Figure 13.3). Where local authorities have
jurisdiction, a 1/4" downward slope is acceptable. Use a drain
tee with a clean out near the exit of the vent (see Figure 13.4)
or allow the condensate to drip out the end.

Figure 13.3 - Horizontal Venting with Upward Pitch

vent terminal

24" min.

(48" min.

in Canada)

Clean out/drip leg

1/4" Slope up towards termination

Listed thimble

Figure 13.4 = Horizontal Venting w/Downward Pitch
(with drip leg)

vent terminal

1/4" Slope down towards termination

24" min.

(48" min.

in Canada)

Tee with drip leg and cleanout cap at low
point of vent system

Listed Thimble

Figure 13.2 - Vent Construction through
Combustible Wall

9-511.4

13

INSTALLATION

Utilizing Outside Combustion Air (Optional)

1. An accessory combustion air intake collar is required for
connecting the combustion air piping to the burner box. For
outdoor installation, the air intake collar connects directly to
the accessory air intake cap.

2. All units may utilize a maximum of 20' of 4" O. D. fresh air
intake pipe with two (2) 90° elbows, 25' with one (1) elbow, or
30' with no elbows.

3. Modine recommends using 4" insulated (sealed) pipe or

Schedule 40 PVC pipe to provide fresh air and limit
condensation from forming on outer surface. A Modine­specified accessory screened combustion air intake cap is
required.

4. Insure that air intake cap is protected from snow blockage.

5. Keep intake opening at least 5 feet from any exhaust vent

opening.

6. Where practical, the outside combustion air intake is

recommended to be in the same pressure zone as the vent
termination.

Gas Connections

WARNING

1. All field gas piping must be pressure/leak tested prior to
operation. Never use an open flame. Use a soap solution
or equivalent for testing.

2. Gas pressure to the appliance controls must never exceed

14” W.C. (1/2 psi).

3. To reduce the opportunity for condensation, the minimum

sea level input to the appliance, as indicated on the serial
plate, must not be less than 5% below the rated input.

4. A certified flexible connector must be used (local codes
permitting) as the method of connecting the heaters to the
gas supply to avoid placing stress on the gas supply line
due to the expansion of the low intensity infrared tubes
during operation.

1. Installation of piping must conform with local building codes,
or in the absence of local codes, of the National Gas Fuel
Code, ANSI Z223.1 (NFPA 54) – Latest Edition. In Canada,
installation must be in accordance with CAN/CGA-B149.1 for
natural gas units and CAN/CGA-B149.2 for propane units.

2. Piping to units should conform with local and national
requirements for type and volume of gas handled, and
pressure drop allowed in the line. Refer to Table 19.1 to
determine the cubic feet per hour (cfh) for the type of gas and
size of unit to be installed. Using this cfh value and length of
pipe necessary, determine the pipe diameter from Table 19.1.
Where several units are served by the same main, the total
capacity, cfh, and length of main must be considered. Avoid
pipe sizes smaller than 1/2". Table 19.1 allows for a 0.3" W.C.
pressure drop in the supply pressure from the building main
to the unit. The inlet pressure to the unit must be 6" W.C. for
natural gas and 11-14" W.C. for propane gas. The gas supply
pressure must never exceed 14" W.C. If the pressure exceeds
14" W.C., a gas pressure regulator must be added upstream
of the combination gas valve. When sizing the inlet gas pipe
diameter, make sure that the unit supply pressure can be met
after the 0.3" W.C. has been subtracted. If the 0.3" W.C.
pressure drop is too high, refer to the Gas Engineer’s
Handbook for other gas pipe capacities.

CAUTION

1. Purging of air from gas supply line should be performed
as described in ANSI Z223.1 - latest edition “National Fuel
Gas Code”, or in Canada in CAN/CGA-B149 codes.

2. When leak testing the gas supply piping system, the
appliance and its combination gas control must be
isolated during any pressure testing in excess of 14" W.C.
(1/2 psi).

3. The unit should be isolated from the gas supply piping
system by closing its field installed manual shut-off
valve.This manual shut-off valve should be located within
6' of the heater.

4. Turn off all gas before installing appliance.

3. Install a ground joint union with brass seat and a manual
shutoff valve adjacent to the unit for emergency shut-off and
easy servicing of controls, including a 1/8" NPT plugged
tapping immediately upstream of the gas supply connection
to the heater, accessible for test gauge connection. See
Figure 15.1.

4. Provide a sediment trap before each unit and in the line
where low spots cannot be avoided. (See Figure 15.1).

5. A certified, metallic stainless steel connector (local codes
permitting) of at least ¾” minimum ID by 36” long, must be used
as the method of connecting the heater to the gas supply line.
The connector must be certified to ANSI Z21.24/CSA 6.10. A
flexible connector avoids placing stress on the gas supply line
due to the thermal expansion of the unit while operating

Canadian installation codes do not permit the use of flexible

metallic connectors. In Canada, Installation Code CAN/
CSA-B149.1-05 requires the use of a Type I hose connector
certified to CSA CAN/CGA-8.1. Use a hose that is of the same
diameter and length as noted above. The certified flexible
connectors must be installed as illustrated in Figure 15.2, in one
plane, without any sharp bends, kinks, or twists. The gas
take-off from the drop line must be parallel to the burner gas
inlet connection.

6. Under no circumstances should the gas supply line to the
heater provide any assistance in the suspension of the
heater. Do not locate any gas service line directly above or
below the heater.

14

9-511.4

INSTALLATION

7. When pressure/leak testing pressures above
14" W.C. (1/2 psi), close the field installed shut-off valve,
disconnect the unit, and its combination gas control from the
gas supply line, and plug the supply line before testing. When
testing pressures 14" W.C. (1/2 psi) or below, close the
manual shut-off valve on the unit before testing.

8. If the gas valve was rotated to change control access side,
leak test fittings

Figure 15.1 - Recommended Sediment Trap/
Manual Shut-Off Valve Installation

SUPPLY LINE

Table 15.1 -

GAS

SUPPLY LINE

MANUAL GAS

TRAP

SHUT-OFF VALVE

PLUGGED

1/8" NPT TEST

GAGE CONNECTION

GAS

3"

MIN.

SEDIMENT

3/4" x 36" Flexible GasConnector Pressure

GROUND

JOINT

UNION

W/ BRASS

SEAT

TO

CONTROLS

Drop ("W.C.)

Input MBH

Natural Propane

50 0.03 0.02

60 0.04 0.02

75 0.05 0.03
100 0.08 0.04
150 0.14 0.07
175 0.18 0.09
200 0.23 0.11

Gas Type

Figure 15.2 - Recommended Installation of Flexible
Gas Connector

Alternate Supply Locations
should be maintained on a
12" radius arc

Field Supplied Gas Piping
Note: The gas supply nipple
must be parallel to the

12"

2"

Burner Box

(End View)

Warning:Connectormustbeinstalledinaconguration.Use

only a 36" long connector of 3/4" nominal ID with this heater. This is

offeredasafactorysupplied,eldinstalledaccessory.

heater movement.

Burner Box
(Side View)

Table 15.2 - Gas Pipe Capacities

Gas Pipe Capacities (Up to 14" W.C. Gas Pressure through Schedule 40 Pipe)

Cubic Feet per Hour with Pressure Drop of 0.3" W.C.

Natural Gas - Specific Gravity - 0.60

Propane Gas - Specific Gravity - 1.50
Length Pipe Diameter
Of Pipe 1/2" 3/4" 1" 1-1/4" 1-1/2" 2"
(feet) Natural Propane Natural Propane Natural Propane Natural Propane Natural Propane Natural Propane

10 132 83 278 175 520 328 1050 662 1600 1008 3050 1922
20 92 58 190 120 350 221 730 460 1100 693 2100 1323
30 73 46 152 96 285 180 590 372 890 561 1650 1040
40 63 40 130 82 245 154 500 315 760 479 1450 914
50 56 35 115 72 215 135 440 277 670 422 1270 800
60 50 32 105 66 195 123 400 252 610 384 1150 725
70 46 29 96 60 180 113 370 233 560 353 1050 662
80 43 27 90 57 170 107 350 221 530 334 990 624
90 40 25 84 53 160 101 320 202 490 309 930 586
100 38 24 79 50 150 95 305 192 460 290 870 548
125 34 21 72 45 130 82 275 173 410 258 780 491

150 31 20 64 40 120 76 250 158 380 239 710 447

9-511.4

15

INSTALLATION - HIGH ALTITUDE ACCESSORY KIT

HIGH ALTITUDE ACCESSORY KIT

Modine’s gas-fired equipment standard input ratings are
certified by ETL. For elevations above 2,000', ANSI Z223.1
requires ratings be reduced 4 percent for each 1000' above sea
level. For units in Canada, CSA requires that ratings be reduced
10 percent at elevations above 2,000'. The high altitude
adjustment instructions and pressure switch kits listed in this
manual are for use with units that will be installed over 2,000'
These methods and kits comply with both ANSI Z223.1 and
CSA requirements.

If a unit is to be installed at higher elevations AND converted from
natural gas to propane gas operation, a propane conversion kit
must be used in conjunction with the pressure adjustment
methods and pressure switch kits listed herein. For the Selection
and Installation Instructions for propane conversion kits, please
see the latest revision of Modine Manual 75-538.

Selection of the Proper Pressure and Kit

To determine the proper manifold pressure at altitude and if
required, the proper combustion air pressure switch kit, the full
model number of the heater, the fuel to be used, and the
altitude the unit will be installed at must be known. Refer to the
unit serial plate or carton label to obtain the necessary
information about the unit.

After obtaining this information, refer to the gas pressure and
selection charts shown in Tables 16.1 through 17.1. The
pressure charts are differentiated by elevation, fuel type, and
country the product is being installed in. The selection charts
are differentiated by product type, altitude and fuel type.
Selection charts include the proper kit suffix, when required.

Manifold Pressure Adjustment

The inlet pressure to the unit must be confirmed to be within
acceptable limits (6-7" W.C. for natural gas and 11-14" W.C.
for propane gas) before opening the shutoff valve or the
combination gas valve may be damaged.

Heaters for use with natural gas, the manifold pressure must
be set at 3.5” W.C. for high fire and 2.5" W.C. for low fire.

Units for use with propane gas, the manifold pressure must be
set at 10.0" W.C. for high fire and 6.2" W.C. for low fire.

Installation above 2,000'. elevation requires adjustment of the
manifold pressure as described.

Derated BTU Content Gas and Manifold Pressure
Calculation

Some utility companies may derate the BTU content (heating
value) of the gas provided at altitude to a value other than 1,050
BTU/ft3 for natural gas or 2,500 BTU/ft3 for propane gas to allow
certain heating appliances to be used with no manifold pressure
adjustments. For this reason it is necessary that the supplying
utility be contacted for detailed information about the gas type
and BTU content (heating value) before operating any heater.
Tables 16.1 and 16.2 show the standard derated heating values
(4% per 1,000' of elevation in the USA and 10% between 2,001’
and 4,500' elevation in Canada) of natural and propane gases
at various altitudes. If the utility is supplying gas with heating
values as shown in Tables 16.1 and 16.2, the manifold pressure
should be set to 3.5" W.C for natural gas and 10.0" W.C. for
propane gas.

NOTE: Both the high fire and low fire gas pressure must be
adjusted for proper operation.

Table 16.1 - Natural Gas Heating Values at
Altitude 

Altitude (ft)

0-2,000 1,050 1,050

2,001-3,000 929

4,001-4,500 874
4,501-5,000 856 856
5,001-6,000 822 822
6,001-7,000 789 789
7,001-8,000 757 757
8,001-9,000 727 727

9,001-10,000 698 698

 Values shown are for 3.5" W.C. manifold pressure, for other BTU content values (available from local utility) use Equation 17.1 to calculate manifold pressure.
 Values shown are for 10.0" W.C. manifold pressure, for other BTU content values (available from local utility) use Equation 17.1 to calculate manifold pressure.
 When installed at altitudes above 2,000', a pressure switch may need to be changed. Refer to Table 17.1 to determine if a switch change is required.
 Gas heating values are derated 4% per 1,000' of elevation in the USA and 10% between 2,000' and 4,500' elevation in Canada in accordance with ANSI Z223.1

and CSA-B149, respectively.

Gas Heating Values at Altitude (BTU/ft3)

USA Canada

9453,001-4,000 892

Table 16.2 - Propane Gas Heating Values at
Altitude 

Altitude (ft)

0-2,000 2,500 2,500

2,001-3,000 2,212

4,001-4,500 2,080
4,501-5,000 2,038 2,038
5,001-6,000 1,957 1,957
6,001-7,000 1,879 1,879
7,001-8,000 1,803 1,803
8,001-9,000 1,731 1,731

9,001-10,000 1,662 1,662

Gas Heating Values at Altitude (BTU/ft3)

USA Canada

2,2503,001-4,000 2,123

16

9-511.4

INSTALLATION - HIGH ALTITUDE ACCESSORY KIT

Table 17.1 - High Altitude Kits for IPT

Conversion IPT - Natural Gas 50 60 75 100 125 150 175 200

0-2000 FT 77823 77824

2001-3500 FT

3501-4000 FT

4001-4500 FT

4501-5000 FT

5001-5500 FT

5501-6000 FT
6001-6500 FT

6501-7500 FT

Conversion IPT - LP 50 60 75 100 125 150 175 200

0-2000 FT

2001-3500 FT

3501-4000 FT

4001-4500 FT

4501-5000 FT

5001-5500 FT

5501-6000 FT

6001-6500 FT

6501-7500 FT

77831

77836

77839

77847

77850

77832

77825

77834

77838

77840 77841 77842

77851

77854 77855

77837

77852 77853

77826 77827 77828 77829 77830

77843 77844 77845

77846

If the heating value of the gas being supplied is different than
the values shown in Tables 16.1 and 16.2, use the following
equation to determine the appropriate manifold pressure for the
altitude and gas heating value being supplied.

Equation 17.1 - Manifold Pressure for Derated Gas

WHERE:

M P

BTU

BTU

MPSL = Manifold Pressure (in. W.C.), at Sea Level –

NOTE: High and Low fire manifold pressure must both be

adjusted using the calculation shown in 17.1.

= Manifold Pressure (in. W.C.) at Altitude –

ACT

Manifold pressure setting for the heater
being installed

= BTU/ft3 Content of Gas –

TBL

Obtained from Tables 16.1 or 16.2
(whichever is applicable)

= BTU/ft3 Content of Gas –

ACT

Obtained from the local utility company

Use 3.5" W.C. for natural gas and 10.0" W.C. for
propane gas

9-511.4

17