Figure 2
GAS SUPPLY
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.
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.
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 the appliance connected; control valve
will sustain damage!
Pressure Testing of the Gas Supply System
Attention!
Checking Manifold Pressure
1. To check the inlet pressure to the gas valve, a 1/8" (3 mm)
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).
If one of the above 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.
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 4.0" w.c.(.996kPa) at the
valve outlet with the inlet pressure to the valve from a
minimum of 5.0" w.c.(1.245kPa) for the purpose of input
adjustment to a maximum of 10.5" w.c.(2.61kPa). 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" (3mm) N.P.T. plugged tapping, accessible for test gauge
connection, is located on the outlet side of the gas control.
Locating Gas Supply
Recommended Gas Pipe Diameter
Note:
Note:
The gas line can enter the unit either through the floor or
outside wall. The gas line opening should be made at this time.
Location of the opening will be determined by the position of
floor joists and the valve and union used for servicing.
Never use plastic pipe. Check to confirm whether your
local codes allow copper tubing or galvanized.
Since some municipalities have additional local codes,
it is always best to consult your local authority and installation
code.
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.
Consult the current National Fuel Gas Code, ANSI Z223.1
CAN/CGA-B149 (.1 or .2) installation code.
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
installation or relocation.
Installing a New Main Gas Cock
Pipe Lenght
(Feet)
Schedule 40 Pipe
Inside Diameter
Tubing, Type L
Outside Diameter
Nat.
1/2”
1.3 cm
5/8”
1.6 cm
3/4”
1.9 cm
7/8”
2.2 cm
L.P.
3/8”
1.0 cm
1/2”
1.3 cm
1/2”
1.3 cm
3/4”
1.9 cm
0 - 10
10 - 40
40 - 100
100 - 150
Figure 1
3” (76 mm)
DRIP LEG
Alternate locations
for shut off valve
Gas supply inlet
NPT Niple
NPT Niple
Close Niple
Shut Off
Valve
NPT Gas
Supply
NPT Union
Flare Fitting
Flex
Tubbing
Flare Shut
Off Valve
Gas
Supply
Tee
Handle
Tee Handle
FLEXIBLE GAS LINE CONNECTION
RIGID GAS LINE CONNECTION
Page 6
L.P.
3/8”
1.0 cm
1/2”
1.3 cm
1/2”
1.3 cm
1/2”
1.3 cm
Nat.
1/2”
1.3 cm
1/2”
1.3 cm
1/2”
1.3 cm
3/4”
1.9 cm
MV1XX-1-0603
