Installation and Service Manual
14
6-563.9
INSTALLATION - GAS CONNECTIONS
GAS CONNECTIONS
1. Installation of piping must conform with local building codes,
or in the absence of local codes, with the National Fuel Gas
Code, ANSI Z223.1 (NFPA 54) - latest Edition. In Canada,
installation must be in accordance with CSA-B149.1.
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 14.1 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 the
length of pipe necessary, determine the pipe diameter from
Table 14.2. 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 14.2
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 6-7" W.C. for natural gas and 11-14" W.C. for
propane gas. 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.
3. Install a ground joint union with brass seat and a manual
shut-off valve adjacent to the unit for emergency shut-off and
easy servicing of controls, including a 1/8" NPT plugged
tapping accessible for test gauge connection (see Figure 14.1).
4. Use 2 wrenches when connecting field piping to units.
5. Provide a sediment trap before each unit in the line where
low spots cannot be avoided. (see Figure 14.1).
6. When pressure/leak testing, pressures above 11" W.C.
(1/2 psi), close the field installed shut-off valve, disconnect
the appliance 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 appliance before testing.
Figure 14.1 - Recommended Sediment Trap/Manual
Shut-off Valve Installation - Side or Bottom Gas
Connection j
GAS
SUPPLY LINE
GAS
SUPPLY LINE
GROUND
JOINT
UNION
MANUAL
SHUT-OFF
VALVE
3"
MIN.
SEDIMENT
TRAP
PLUGGED
1/8" NPT TEST
GAUGE CONNECTION
TO
CONTROLS
jManual shut-off valve is in
the “OFF” position when
handle is perpendicular
Pipe
Length (ft.)
Natural Gas
1/2" 3/4" 1" 1-1/4" 1-1/2" 2"
10 132 278 520 1050 1600 3050
20 92 190 350 730 1100 2100
30 73 152 285 590 890 1650
40 63 130 245 500 760 1450
50 56 115 215 440 670 1270
60 50 105 195 400 610 1150
70 46 96 180 370 560 1050
80 43 90 170 350 530 930
100 38 79 150 305 460 870
125 34 72 130 275 410 780
150 31 64 120 250 380 710
Table 14.2 - Gas Pipe Capacities - Natural Gas jk
jCapacities in cubic feet per hour through Schedule 40 pipe with maximum
0.3" W.C. pressure drop with up to 14" W.C. gas pressure. Specific gravity is 0.60
for natural gas and 1.50 for propane gas.
k For pipe capacity with propane gas, divide natural gas capacity by 1.6. Example:
What is the propane gas pipe capacity for 60 feet of 1-1/4" pipe? The natural gas
capacity is 400 CFH. Divide by 1.6 to get 250 CFH for propane gas.
Table 14.1 - Sea Level Manifold Pressure &
Gas Consumption
WARNING
1. Installation must conform with local building codes or in
the absence of local codes, with the National Fuel Gas
Code, ANSI Z223.1 (NFPA 54) - latest edition. In Canada
installation must be in accordance with CSA B149.1.
2. 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.
3. Gas pressure to appliance controls must never exceed
14" W.C. (1/2 psi).
4. 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, or
5% below the minimum rated input of dual rated units.
CAUTION
1. Purging of air from gas lines should be performed as
described in the National Fuel Gas Code, ANSI Z223.1
(NFPA 54) - latest edition, or in Canada CSA-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.
IMPORTANT
To prevent premature heat exchanger failure, the input to
the appliance, as indicated on the serial plate, must not
exceed the rated input by more than 5%.
Natural Propane
Model
Size
Manifold Pressure
("W.C.):
3.5 10
# of
Orifices
55
CFH 54.0 22.1
4
Gal/Hr. Propane n/a 0.61
Orifice Drill Size 50 1.10 mm
65
CFH 65.6 26.3
5
Gal/Hr. Propane n/a 0.73
Orifice Drill Size 1.75 mm 57
85
CFH 81.0 34.0
5Gal/Hr. Propane n/a 0.9
Orifice Drill Size 47 1.25 mm
110
CFH 105.0 44.0
5Gal/Hr. Propane n/a 1.2
Orifice Drill Size 43 54
135
CFH 128.6 54.0
6Gal/Hr. Propane n/a 1.5
Orifice Drill Size 43 54
156
CFH 147.6 62.0
6Gal/Hr. Propane n/a 1.7
Orifice Drill Size 41 1.50 mm
180
CFH 171.4 72.0
7Gal/Hr. Propane n/a 2.0
Orifice Drill Size 41 53
215
CFH 204.8 86.0
9Gal/Hr. Propane n/a 2.4
Orifice Drill Size 42 54
260
CFH 247.6 104.0
9Gal/Hr. Propane n/a 2.9
Orifice Drill Size 38 52
310
CFH 295.2 124.0
12
Gal/Hr. Propane n/a 3.4
Orifice Drill Size 41 53