9
34-55 08/14
5
GAS SUPPLY AND PIPING
Verify that the type of gas specified on rating plate is supplied to the unit. This unit is orificed for operation up to 2000
feet altitude. Appliance btuh output derates 4% per 1000 feet elevation above sea level. Consult Factory for
installations above 2000 feet elevation.
5.1 Inlet Pressure:
Measured at the inlet pressure tap located at the main gas cock. The inlet pressure must remain
within the minimum and maximum values while the unit is at rest and while the unit is operating at maximum firing
rate.
5.2 Manifold Pressure:
Measure at the pressure tap on the downstream side of the manual shutoff valve closest to the
burner. The rated manifold pressure appears on the product data label located on the front of the appliance.
5.3 Gas Piping Size:
Use the values in “Convert Fittings To Equivalent Straight Pipe” to add the equivalent straight pipe
for each elbow or tee to obtain the total distance from the meter. Use this corrected total distance from the meter for
determining the suggested pipe size in the “Single Unit Installation Suggested Gas Pipe Size” table.
*Multiplier for Propane: 1.57
**Multiplier for alternate pressure drops: 0.3" W.C. 0.77; 1.0" W.C. 1.41; 2.0" W.C. 2.00; and 4.0" W.C. 2.82.
INLET PRESSURE
NAT. GAS
LP
Maximum Static Pressure (Inches-Water Column)
14"
13"
Minimum Flow Pressure (Inches-Water Column)
4.5"
11"
CONVERT FITTINGS TO EQUIVALENT STRAIGHT PIPE
Diameter Fitting (inches)
¾" 1" 1¼" 1½"
2"
3" 4" 5"
Equivalent Length of
Straight Pipe (feet)
2' 2' 3' 4' 5' 10' 14' 20'
Equivalent Feet From
Meter
SINGLE UNIT INSTALLATION SUGGESTED PIPE SIZE
Maximum Capacity for Natural Gas*
MBTU/HR Based on 0.5" W.C. Pressure Drop**
1-1/4" 1-1/2" 2"
2½"
3"
4"
25
860 1320 2475 3900 7000 -
40 660
990
1900
3000
5300
-
60 -
810
1520
2400
4300
-
80 -
690
1300
2050
3700
-
100
-
620 1150 1850 3250 6700
125
-
- 1020 1650 2950 6000
150 -
-
950
1500
2650
5500
175 -
-
850
1370
2450
5000
200 -
-
800
1280
2280
4600