Unitary products group P HU Series User manual

Unitary Products Group
ACCESSORY KIT INSTALLATION INSTRUCTIONS
HIGH ALTITUDE APPLICATION CONVERSION
MID-EFFICIENCY SINGLE-STAGE INDUCED COMBUSTION FURNACES
MODELS: P*HU/G8T-UH/L8T-UH/FL8 UPFLOW / HORIZONTAL
P*DN/G8T-DN/L8T-DN DOWNFLOW
035-14446-000 Rev. B (1002)
GENERAL
This instruction is intended for the conversion of new equip-
ment only, for operation at altitudes greater than 4,500 ft.
above sea level. Follow the basic unit installation instruction
for all other aspects of the installation.
All units are equipped to operate up to 4,500 feet above sea
level without a high altitude kit. 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
detailed below.
.
* May be any numeral 0-9.
PRESSURE SWITCH
For installations below 4500 ft., refer to furnace installation
instructions to properly derate applications which do not
require a pressure switch change. For applications above
4,500 feet, a pressure switch change is required to provide
safe and reliable operation. Table 1 indicates the correct
pressure switch accessory for each unit model applied.
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, per-
sonal injury or loss of life. The qualified service agency is responsible for the proper installation of this kit. The installa-
tion 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.
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-lat-
est edition, unless superseded by local codes. For Canadian installations, the conversion shall be carried out in accor-
dance 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.
Improper installation, adjustment service, or mainte-
nance can cause injury or property damage; there-
fore, only a qualified installer or qualified service
personnel should perform this conversion.
COMMON PARTS
Description Part Number Quantity
Conversion Label 035-11635-000 1
Install. Instruction. 035-14446-000 1
PRESSURE SWITCH
Accessory Kit Switch Part Number Pressure Setting
1PS0301 024-27669-00* .35 IWG
1PS0302 024-27627-00* .42 IWG
1PS0311 024-27626-00* .40 IWG
1PS0312 024-27628-00* .45 IWG
Do not adjust the original pressure switch to allow
operation at high altitude. Unsafe operation will
result.
Table 1:
HIGH ALTITUDE PRESSURE SWITCH USAGE
INPUT
(MBH) OUTPUT (MBH) ACCESSORY PART NUMBER
Upflow / Horizontal & Downflow Models
40 32 1PS0301
57 46 1PS0301
80 64 1PS0301
100 80 1PS0311
115 92 1PS0311
130 104 1PS0311
160 130 1PS0301

035-14446-000 REV. A (0301)
2Unitary Products Group
The high altitude pressure switch should be changed by fol-
lowing this procedure.
1. Remove the burner access door.
2. Note the location of the wires on the pressure control
and then disconnect them. Remove the hose from the
pressure control.
3. Remove the screws securing the pressure control and
remove it from the unit. Check that the new pressure
control kit is correct for your application (Refer to “Pres-
sure Switch” Table on page 1). Install the new pressure
control.
4. Replace the hose and wiring as originally connected.
ORIFICE SIZE SELECTION
A number of factors determine the correct orifice usage for
your application. These factors include the original orifice siz-
ing, BTU content of the gas and the altitude.
For natural gas applications, contact your gas supplier for the
actual BTU content (heating value) of the fuel provided at
your altitude. Table 3 indicates various BTU content fuels.
The standard orifice used in the furnace is shown in Table 2.
Find your unit and determine the standard orifice provided.
Use the BTU heating value from Table 3 or 4 that is nearest
to your value. Read across the selected table from the stan-
dard orifice to the altitude for your application and note the
new orifice size.
EXAMPLE: If your unit has a #45 orifice as standard and a
heating gas value of 900 BTU/CU.FT., at an altitude of 7,000
feet a #47 orifice will provide the correct firing rate.
For propane (LP) applications, Use Table 4 to select the
proper high altitude orifice size.
After selecting the proper orifice size for your application, see
Table 5 for the listing that indicates the part number for your
required orifice number. The orifices may be obtained
through your local Source 1 Parts Distribution Center.
The high altitude orifices should be changed by the following
procedure:
1. Carefully remove the wires from the gas valve and note
their location so they may properly replaced. Remove
the four screws that hold the manifold to the manifold
support bracket and slide the manifold and orifices back
out of the burners.
2. Remove the main burner orifices from the manifold and
discard them.
3. Install the derate main burner orifices in the manifold and
tighten them.
4. Reinstall the manifold in the assembly by reversing the
removal process.
The gas supply shall be shut off prior to discon-
necting the electrical power, before proceeding
with the conversion.
The furnace must first be converted to use pro-
pane (LP) through the use of the standard propane
conversion kit accessory.
Table 2: STANDARD ORIFICE USAGE
INPUT
(MBH) OUTPUT (MBH) NATURAL ORIFICE SIZE PROPANE ORIFICE SIZE
Upflow/Horizontal & Downflow Models
40 32 #45 #55
57 46 #45 #56
80 64 #45 #55
100 80 #45 #55
115 92 #45 #55
120 96 #45 #56
130 105 #45 #56
160 130 #43 #54

035-14446-000 Rev. B (1002)
Unitary Products Group 3
5. Install the high altitude conversion labels as described in
the LABELS sections of this instruction on Page 4.
6. Refer to the unit installation instructions to complete the
installation before continuing with these procedures.
TESTS AND ADJUSTMENTS
The following tests must be performed at the time of conver-
sion following completion of the installation.
1. Connect a manometer to the pressure tap on both the
inlet and outlet side of the gas valve. Connect a power
supply and a gas supply to the unit, if not already con-
nected.
2. Turn on the gassupply and bleed air from the gas supply
lines at a point as close to the inlet or the gas valve as is
practical.
3. Turn the gas valve control knob to the ON position.
4. Make sure unit electrical disconnect switch is in the OFF
position.
5. Set the room thermostat to call for heat.
Table 3: ALTITUDE/NATURAL GAS HEATING VALUE ORIFICE SELECTION
NATURAL GAS
HEATING VALUE
(MANIFOLD
PRESSURE
3.5" W.C.)
ORIFICE
SHIPPED
WITH UNIT
RECOMMENDED ORIFICE
ALTITUDE (FT. ABOVE SEA LEVEL)
0 2,000 3,000 4,000 5,000 6,000 7,000 8,000 9,000 10,000
1200 BTU/CU Ft. 45 48 49 49 50 50 50 51 51 52 52
43 45 46 47 47 47 48 48 49 49 49
1100 BTU/CU.FT. 45 47 48 48 49 49 49 50 50 51 51
43 44 45 45 45 46 47 47 48 48 49
1000 BTU/CU.FT. 45 45 46 47 47 47 48 48 49 49 50
43 43 44 44 44 45 45 46 47 47 48
900 BTU/CU.FT. 45 44 45 45 45 46 47 47 48 48 49
43 42 42 43 43 43 44 44 45 46 47
800 BTU/CU.FT. 45 43 44 44 44 45 45 46 47 47 48
43 39 40 41 41 42 42 43 43 44 44
Table 4: ALTITUDE/PROPANE (LP) GAS HEATING VALUE ORIFICE SELECTION
PROPANE GAS HEATING
VALUE (MANIFOLD
PRESSURE 10.0” W.C.)
PROPANE
ORIFICE @
SEA LEVEL
RECOMMENDED ORIFICE
ALTITUDE (FT. ABOVE SEA LEVEL)
0 2,000 3,000 4,000 5,000 6,000 7,000 8,000 9,000 10,000
2516 BTU/CU FT. 54 54 54 55 55 55 55 55 56 56 56 55 55 55 55 55 56 56 56 56 56 57
56 56 56 56 57 57 57 58 59 59 60
Table 5: ORIFICE PART NUMBERS
BURNER ORIFICES
Size # Source 1 Part Number
Blank 029-20423-000
41 029-20423-041
42 029-20423-042
43 029-24243-043
44 029-20423-044
45 029-20423-045
46 029-20423-046
47 029-20423-047
48 029-20423-048
49 029-20423-049
50 029-20423-050
51 029-20423-051
52 029-20423-052
55 029-20423-055
56 029-20423-056
57 029-20423-057
58 029-20423-058
59 029-20423-059
60 029-20423-060
Make sure both gas and power supplies are shut
off before proceeding.
Make sure the space is free of gas before pro-
ceeding.

Subject to change without notice. Printed in U.S.A. 035-14446-000 Rev. B (1002)
Copyright © by York International Corp. 2002. All rights reserved. Supersedes: 035-14446-000 Rev. A (0301)
Unitary 5005 Norman
Product York OK
Group Drive 73069
6. Turn unit electrical disconnect switch to ON. The com-
bustion blower should start and the hot surface igniter
should start glowing.
7. After air has been purged from the gas supply line, igni-
tion should occur. Shortly after ignition, the manifold and
gas inlet pressures can be checked on the manometers.
Main burner ignition may be delayed on the first ignition
cycle due to air in the gas manifold.
8. Adjust manifold pressure to specifications shown in
Table 6. This setting will result in an input which is prop-
erly derated for your altitude. Supply gas must be within
the range shown in Table 6. If required, adjust the incom-
ing regulator spring so that the pressure falls within the
range.
9. Observe several ignition cycles. All main burners must
ignite without delayed ignition or burning at the orifices. If
delayed ignition is observed, verify that the igniter is
properly mounted (not loose or crooked on bracket, and
that bracket screws are not loose).
10. If burning at the orifices, excessive yellow tipping, or
excessive noise is observed during any phase of main
burner operation, correct unit operation.
11. With the main burners ignited, check for gas leaks,
especially in the following locations: gas valve inlet and
outlet connections, manifold union in the burner compart-
ment, and main burner orifices where they thread into
the manifold. Repair any leaks found and recheck.
12. Operate the furnace for 15 minutes and measure the
supply and return air temperatures. Verify that the tem-
perature rise (supply air - return air rise) is within the
allowable range. See the unit data plate for the minimum/
maximum allowable temperature rise. If the measured
rise is in excess of the maximum shown on the data
plate, a higher blower speed must be selected. See the
unit wiring diagram to make this change.
13. During unit operation, the main burner appearance and
igniter location should be as shown below:
14. With the main burners off, disconnect the manometers
and replace the plugs. Check for gas leakage at the
plugs.
15. Replace all access panels.
LABELS
1. Remove label 035-11635-000 from the shipping box.
Check the Normal to High Altitude.
NOTE: If the unit has been converted from natural gas to pro-
pane (LP), place the new label over the existing label and fill
in the appropriate information.
2. Under "Rating After Conversion", write in the following:
a. Orifice size, as stamped on the orifice
b. Maximum inlet pressure
c. Minimum inlet pressure
d. Manifold pressure for both low and high inputs
e. Input ratings, same as on the rating plate
f. Outlet ratings, same as on the rating plate
3. Under "Changes After Conversion", write in the follow-
ing:
a. Kit number, located on the outside of the box.
b. Unit model
c. Stamp or write in the name of the organization mak-
ing conversion, address, city, state, month and year.
4. Remove label backing and affix label adjacent to the Rat-
ing Plate.
5. On propane (LP) conversions, affix the corresponding
gas valve label (provided in the conversion kit) to the
valve.
Table 6: GAS PRESSURES
NATURAL GAS
Inlet Gas Pressure Must Be
at 4.5” - 13.9” WC at Furnace
Set Manifold Pressure at 3.5” WC
PROPANE (LP) GAS
Inlet Gas Pressure Must Be
at 11” - 13.9” WC at Furnace
Set Manifold Pressure at 10” WC
Do not use an open flame or any source of ignition
to check for leaks.
FIGURE 1: Proper Burner Flame Appearance
BLUE CONE PORTION OF
FLAME SHOULD ENTER
HEAT EXCHANGER TUBE