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INSTALLATION
INSTRUCTION
HIGH ALTITUDE APPLICATION
CONVERSION INSTRUCTION
HIGH EFFICIENCY
DELUXE TWO STAGE
FURNACES
Supersedes: Nothing
650.78-N2.1V (998)
MODELS: P1XU / G9D UPFLOW
P1XD / G9D DOWNFLOW/HORIZONTAL
GENERAL
This instruction is intended for the conversion of new equip-
ment only, for operation at altitudes greater than 2,000 ft.
above sea level. Follow the basic unit installation instruction
for all other aspects of the installation.
All unit installations above 2,000 ft. must be field derated as
required by the National Fuel Gas Code, ANSI Z223.1 (latest
edition), or in Canada, CAN/CGA B149.1 or .2 and all other
applicable local codes and utility requirements.
This instruction provides the necessary information to select
and install both the proper pressure switch and orifice for your
specific application. Data is provided for both natural and
propane (LP) gases. This high altitude pressure switch and
accessory includes a special switch and other items as de-
tailed below.
WARNING: Improper installation, adjustment serv-
ice, or maintenance can cause injury or property
damage; therefore, only a qualified installer or quali-
fied service personnel should perform this conver-
sion.
PRESSURE SWITCH
All units require a pressure switch change to provide safe and
reliable operation at altitudes over 2,000 ft. Table 1 indicates
the correct pressure switch accessory for each unit model
applied at two different altitude groupings.
The high altitude pressure switch should be changed by follow-
ing this procedure.
CAUTION: The gas supply shall be shut off prior to
disconnecting the electrical power, before proceeding
with the conversion.
1. Remove the burner access door.
2. Note the location of the wires on the right hand pressure
control and then disconnect them. Remove the hose from
the pressure control.
035-14460-000
COMMON PARTS
Description
Part Number
Quantity
Conversion Label
035 - 11635 - 000
1
Install. Instruction.
035 - 14460 - 000
1
PRESSURE SWITCH
Accessory Kit
Switch Part Number
Pressure Setting
1PS0315
024-27680
.25 / .75 IWG
1PS0316
024-27681
.30 / .75 IWG
1PS0317
024-27682
.25 / .50 IWG
1PS0318
024-27683
.35 / .80 IWG
WARNING: Do not adjust the original pressure
switch to allow operation at high altitude. Unsafe
operation will result.
Input
(MBH)
Output
(MBH)
2,000 Ft
to 10,000 Ft.
> 2,000
To 10,000 Ft.
Upflow/Downflow Models
60 / 39
55 / 36
1PS0315
1PS0315
80 / 52
74 / 48
1PS0316
1PS0316
100 / 65
93 / 60
1PS0317
1PS0317
120 / 78
112 / 72
1PS0318
1PS0318
TABLE 1
- HIGH ALTITUDE PRESSURE SWITCH USAGE
WARNING: This conversion kit is to be installed by a qualified service agency in accordance with
the manufacturer’s instructions and all applicable codes and requirements of the authority having
jurisdiction. If the information in these instructions is not followed exactly, a fire, an explosion or
production of carbon monoxide may result causing property damage, personal injury or loss of
life. The qualified service agency is responsible for the proper installation of this kit. The
installation is not proper and complete until the operation of the converted appliance is checked
as specified in the manufacturer’s instructions supplied with the kit.
WARNING: The conversion of new certified central heating gas appliances must conform to
directions outlined in this instruction.
Installation must be made in accordance with American National Standard National Fuel Gas Code,
ANSI Z223.1-latest edition, unless superseded by local codes. For Canadian installations, the
conversion shall be carried out in accordance with the requirements of the Provincial authorities
having jurisdiction and in accordance with the CAN1-B149.1 and .2 installation codes.
The manufacturer accepts no responsibility for malfunctions due to improper conversions.