Gas Supply - Re-Verber-Ray ST Series Operation, Installation, Maintenance And Parts Manual

2 INSTALLATION

2.11 Gas Supply

CORRECT INLET PRESSURES ARE VITAL FOR
EFFICIENT OPERATION OF HEATERS. REFER
TO CSA RATING PLATE AND, IF NECESSARY,
CONSULT GAS COMPANY.
If all or a portion of the gas supply line consists of
used pipe, it must be cleaned and then inspected to
determine its equivalency to new pipe. Test all main
supply lines according to local codes. (Isolate heater
gas valve and gas cock during test.)
Excessive torque on manifold may misalign orifice.
Always use two wrenches when tightening mating
pipe connections.
Never use a match or any other flame to test
for gas leaks. Use soap-and-water solution to
check for leaks.
If any portion of the gas supply line is located in an
area that could cause an abnormal amount of
condensate to occur in the pipe, a sediment trap
should be installed.
WARNING
NOTE: For high-pressure gas above 14 in. W.C.
(Water column), a high-pressure regulator and gas
cock must be use. If compressed air is used to detect
leaks in the gas supply line, disconnect and cap at
shutoff cock to avoid damage to regulator and gas
valve.
A typical gas supply line connection is illustrated in
Figure 2.11.1. The method shown will decrease the
possibility of any loose scale or dirt in the supply line
entering the heater's control system and causing a
malfunction. The gas supply line must be of
sufficient size to provide the required capacity and
inlet pressure to the heater (consult gas company) as
follows:
NOTE: Manifold and inlet pressures should be
checked at the tap on the gas valve. Readings will be
above atmospheric pressure.
* Natural Gas
To obtain the required manifold pressure of 3.5 in.
W.C., a minimum inlet pressure of 5.0 in. W.C. is
necessary for purposes of input adjustment. A
maximum inlet pressure of 14.0 in. W.C. is
allowed for all units.
* Propane Gas
To obtain the required manifold pressure of 10.0 in.
W.C., a minimum of 11.0 in. W.C. for purposes
of input adjustment to a maximum of 14.0 in. W.C.
must be provided ahead of the control system on
each heater. Do not exceed a manifold operating
pressure of 10 in. W.C.
Use only a pipe-joint compound that is resistant to
liquified petroleum gases.
* Pressure Equivalents
1 in. W.C. equals 0.58 oz./sq. in.
19