Cambridge Air Solutions
12
SA-Series Technical Manual
INSTALLATION INSTRUCTIONS
GAS PIPING
IMPORTANT
Refer to the heater nameplate for determining the
minimum gas supply pressure for obtaining the
maximum gas capacity for which this heater is specified.
1. Check with the local utility or gas supplier to
determine the gas supply pressure.
CAUTION:
If the gas supply pressure is in excess of the maximum
pressure indicated (14" WC) on the heater nameplate,
a separate positive shutoff high pressure regulator must
be added upstream of the heater’s individual manual
shutoff valve. This regulator must be vented to outside
of building at least 10 feet from any intake opening.
The vent pipe should be designed to prevent the entry
of water, snow, insects or other foreign material that
could cause blockage. There must be no reduction in
size of the vent piping. Depending on the length and
the configuration of the vent piping the pipe size may
need to be increased. Refer to the applicable codes
for proper sizing.
2. Properly size the gas supply piping for the rated
input capacity, per local codes, and/or the National
Fuel Gas Code, ANSI Standard Z223.1 or the
CAN/CSA B149 Installation Codes.
3. Make sure the supply piping is free of foreign
matter and purged.
4. Verify that the gas piping, when installed, will not
restrict or block the unit access door from fully
opening.
5. Install the gas piping to the unit in accordance
with local codes or, in their absence, in accordance
with the National Fuel Gas Code, ANSI Standard
Z223.1 or the CAN/CSA B149 Installation Codes.
IMPORTANT
A 1/8" NPT tap is supplied with the heater for measuring
the gas supply pressure. If the gas supply pressure
exceeds that indicated on the nameplate, the installer
must install a 1/8" NPT tap and high pressure manual
shutoff valve upstream of the high gas pressure regulator.
CAUTION:
An adequate sediment trap must be installed
upstream of all gas controls for the heater and as
close to the gas inlet connection of the heater as
practical.
IMPORTANT
Many gas train components are equipped with Listed
Vent Limiters as atmospheric bleeds, however, local
codes may require that these vents and bleeds be
vented to the outdoors. If so, the vent piping should be
designed to prevent the entry of water, snow, insects or
other foreign materials that could cause blockage.
6. Apply test pressure to the supply piping system
and check for leaks. Use liquid gas detector. Do
not use flame.
CAUTION:
If the test pressure is in excess of 1/2 PSIG
(3.45 KPA), the heater and its manual shutoff valve
must be disconnected from the gas supply system
during pressure testing. Failure to comply will void
warranty.
If the test pressure is less than or equal to 1/2 PSIG
(3.5 KPA), the heater must be isolated from the gas
supply piping by closing its manual shutoff valve
during pressure testing.
WARNING:
Do not attempt to start unit at this time. Premature
start-up can result in damage to equipment and
components.
