Check all local codes for requirements, especially for the size and
type of gas supply line required.
Recommended Gas Pipe Diameter
Pipe Length
Schedule 40 Pipe
Inside Diameter
Tubing, Type L
Outside Diameter
Nat.
L.P.
Nat.
L.P.
0-10 feet
0-3 meters
1/2”
12.7 mm
3/8”
9.5 mm
1/2”
12.7 mm
3/8”
9.5 mm
10-40 feet
4-12 meters
1/2”
12.7 mm
1/2”
12.7 mm
5/8”
15.9 mm
1/2”
12.7 mm
40-100 feet
13-30 meters
1/2”
12.7 mm
1/2”
12.7 mm
3/4”
19 mm
1/2”
12.7 mm
100-150 feet
31-46 meters
3/4”
19 mm
1/2”
12.7 mm
7/8”
22.2 mm
3/4”
19 mm
Note:
Never use plastic pipe. Check to confirm whether your local
codes allow copper tubing or galvanized.
Note:
Since some municipalities have additional local codes, it is
always best to consult your local authority and installation code.
Check all local codes for requirements, especially for the size and
type of gas supply line required. On Natural gas lines less than 15'
(4.57m) long, use 1/2" pipe; on longer runs, use 3/4" iron pipe or
equal. On LP gas lines please consult LP gas supplier.
Installing a New Main Gas Cock
Each appliance should have its own manual gas cock.
A manual main gas cock should be located in the vicinity of the
unit. Where none exists, or where its size or location is not ad-
equate, contact your local authorized installer for installation or
relocation.
Compounds used on threaded joints of gas piping shall be resistant
to the action of liquefied petroleum gases. The gas lines must be
checked for leaks by the installer. This should be done with a soap
solution watching for bubbles on all exposed connections, and if
unexposed, a pressure test should be made.
Never use an exposed flame to check for leaks. Appliance must
be disconnected from piping at inlet of control valve and pipe
capped or plugged for pressure test. Never pressure test with
appliance connected; control valve will sustain damage!
A gas valve and ground joint union should be installed in the gas
line upstream of the gas control to aid in servicing. It is required
by the National Fuel Gas Code that a drip line be installed near
the gas inlet. This should consist of a vertical length of pipe tee
connected into the gas line that is capped on the bottom in which
condensation and foreign particles may collect.
Figure 5
The use of the following gas connectors is recommended:
— ANS Z21.24 Appliance Connectors of Corrugated Metal Tubing
and Fittings
— ANS Z21.45 Assembled Flexible Appliance Connectors of
Other Than All-Metal Construction
The above connectors may be used if acceptable by the authority
having jurisdiction. The state of Massachusetts requires that a flexible
appliance connector cannot exceed three feet in length.
Pressure Testing of the Gas Supply System
1. To check the inlet pressure to the gas valve, a 1/8" (3.175mm)
N.P.T. plugged tapping, accessible for test gauge connection,
must be placed immediately upstream of the gas supply
connection to the appliance.
2. The appliance and its individual shutoff valve must be
disconnected from the gas supply piping system during any
pressure testing of that system at test pressures in excess of 1/2
psig (3.5 kPa).
3. The appliance must be isolated from the gas supply piping
system by closing its individual manual shutoff valve during
any pressure testing of the gas supply piping system at test
pressures equal to or less than 1/2 psig (3.5 kPa).
Attention!
If one of the procedures results in pressures in excess
of 1/2 psig (14" w.c.) (3.5 kPa) on the appliance gas valve, it will
result in a hazardous condition.
Checking Manifold Pressure
Both Propane and Natural gas valves have a built-in pressure
regulator in the gas valve. Natural gas models will have a manifold
pressure of approximately 3.5" w.c. (.871kPa) at the valve outlet
with the inlet pressure to the valve from a minimum of 4.5" w.c.
(1.120kPa) for the purpose of input adjustment to a maximum of
10.5" w.c. (2.614kPa) Propane gas models will have a manifold
pressure approximately 10.0" w.c. (2.49kPa) at the valve outlet
with the inlet pressure to the valve from a minimum of 11.0" w.c.
(2.739kPa) for the purpose of input adjustment to a maximum of
13.0" w.c. (3.237kPa).
A 1/8" (3.175mm) N.P.T. plugged tapping, accessible for test gauge
GAS SUPPLY
23813-1-0807
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