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14015-1-0903
GAS SUPPLY
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
Tubing, Type L
(Feet)
Inside Diameter
Outside Diameter
Nat.
L.P.
Nat.
L.P.
0-10
1/2"
3/8"
1/2"
3/8"
1.3 cm
1.0 cm
1.3 cm
1.0 cm
10-40
1/2"
1/2"
5/8"
1/2"
1.3 cm
1.3 cm
1.6 cm
1.3 cm
40-100
1/2"
1/2"
3/4"
1/2"
1.3 cm
1.3 cm
1.9 cm
1.3 cm
100-150
3/4"
1/2"
7/8"
3/4"
1.9 cm
1.3 cm
2.2 cm
1.9 cm
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.
Installing a New Main Gas Cock
Each appliance should have its own manual gas cock.
In the state of Massachusetts the gas cock must be a T handle
type.
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
adequate, contact your local authorized installer for installa-
tion 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 pres-
sure test with appliance connected; control valve will sus-
tain 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.
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.
Figure 4
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
VSR
Natural gas models will have a manifold pressure of
approximately 3.5" w.c. (.871kPa) at the pressure regulator outlet
with the inlet pressure to the pressure regulator from a minimum
of 4.5" w.c. (1.120kPa) for the purpose of input adjustment to a
maximum of 10.5" w.c. (2.615kPa).
VSM
Natural gas models
will have a manifold pressure of approximately 4.5" w.c. (1.12kPa)
at the pressure regulator outlet with the inlet pressure to the
pressure regulator from a minimum of 7.0" w.c. (1.74kPa) for the
purpose of input adjustment to a maximum of 10.5" w.c.
(2.615kPa).
VSR and VSM
Propane gas models will have a
manifold pressure approximately 10.0" w.c. (2.49kPa) at the
pressure regulator outlet with the inlet pressure to the pressure
regulator 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).
VSM
Note:
A test gage connection is located downstream of the gas
appliance pressure regulator for measuring gas pressure. The
connection is a 1/8 inch 3mm) N.P.T. plugged tapping.
VSR
Note:
The gas control is equipped with a captured screw type
pressure test point, therefore it is not necessary to provide a 1/8"
test point up stream of the control.
