18
Installation Guide
| Comfort Pack with 80% Gas Heat
NOTE: THIS ADJUSTMENT CAN ONLY BE DONE
AFTER THE HEATER IS IN OPERATION. IT IS
INCLUDED IN THE STARTUP PROCEDURES
VALVE OUTLET PRESSURE
SETTINGS BY ELEVATION
ALTITUDE
NATURAL GAS
(Inches w.c.)
PROPANE GAS
(Inches w.c.)
Feet
0-2000
3.5
10.0
2001-3000
2.8
7.7
3001-4000
2.5
7.1
4001-5000
2.3
6.4
5001-6000
2.1
5.8
6001-7000
1.9
5.2
7001-8000
1.7
4.6
8001-9000
1.5
4.1
2.
With the manual valve positioned to prevent flow to the main
burner, connect a manometer to the 1/8” pipe outlet pressure
tap in the valve. Use a water column manometer that is
readable to the nearest tenth of an inch.
3.
Remove the cap from the pressure adjusting screw
and adjust the valve outlet pressure to the pressure
setting selected from the table. Cycle the main burner once
or twice to properly seat the adjustment spring in the valve.
Re-check the pressure. If necessary, re-adjust the pressure.
When the pressure is correct, remove the manometer and
replace the cap. Check for leaks at the pressure tap fitting.
4.
With the heater operating determine that the inlet pressure
to the heater for natural gas is between 5 and 13.5 inches
w.c., and for propane between 10 and 13.5 inches w.c. Take
this reading as close as possible to the heater (heaters are
equipped with gas valves that have an inlet pressure tap.) If
the inlet is not within the specified range, the inlet pressure
must be corrected and Steps 3 and 4 repeated.
5.
Find the Valve Outlet Pressure Adjustment label in the plastic
bag that contained these instructions. Using a permanent
marker, fill in the pressure setting. Adhere the label on the
heater near the gas valve so that it is conspicuous to someone
serving the valve.
Instructions for Changing Pressure Switch
1.
Open the burner/control compartment access panel. Locate
the pressure switch.
2.
Mark and disconnect the two wires attached to the pressure
switch.
3.
Disconnect the flow sensing tubing from the pressure switch.
4.
Locate the two screws holding the switch mounting bracket.
Remove the screws (save screws) and the pressure switch.
5.
Install the high altitude pressure switch. Attach the sensing
tube and wires. Replace access panel.
SIZE
P/N
DESCRIPTION
ALL
14208325
Set to break on pressure in-
crease @ -0.5” w.c.
Derating by Valve Outlet Pressure
Adjustment for High Altitude Operation
Instructions
1
.
Determine the required valve outlet pressure for the elevation
where the heater will be operating. If unsure of the elevation,
contact the local gas supplier.
METER TIME IN MINUTES AND SECONDS FOR NORMAL
INPUT RATING OF FURNACES EQUIPPED FOR NATURAL OR LP GAS
INPUT
BTU/
HR
METER
SIZE
CU. FT.
HEATING VALUE OF GAS BTU PER CU. FT.
900
1000
1040
1100
2500
MIN. SEC. MIN. SEC. MIN. SEC. MIN. SEC. MIN. SEC.
50,000
ONE
TEN
1
10
5
50
1
12
12
00
1
12
15
30
1
13
18
12
3
30
20
00
75,000
ONE
TEN
0
7
44
12
0
8
48
0
0
8
50
19
0
8
53
48
2
20
0
0
100,000
ONE
TEN
0
5
33
24
0
6
36
0
0
6
38
15
0
6
40
36
1
15
30
0
125,000
ONE
TEN
0
4
26
19
0
4
29
48
0
5
30
0
0
5
32
17
1
12
12
0
150,000
ONE
TEN
0
3
31
36
0
4
24
0
0
4
25
10
0
4
26
20
1
10
0
0
Input BTU/HR
=
Heating Value of Gas (BTU/Ft
3
) x 3600 x correction factor
Time in Seconds (for 1 cu.ft.) of Gas
Summary of Contents for Comfort Pack U Series
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