Cambridge Air Solutions M Series, Техническое руководство

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Cambridge Air Solutions. 28 M-Series Technical Manual
IMPORTANT
Refer to the heater rating plate for determining
the minimum gas supply pressure for obtaining
the maximum gas capacity for which this heater
is specified. Any field installed components,
including, but not limited to meters, regulators,
pipe elbows , pipe nipples and strainers must
be installed such that the minimum operating
supply pressure for obtaining the maximum
gas capacity is provided.
1. Check with the local utility or gas supplier for the
facility gas supply pressure.

CAUTION:
If the gas supply pressure is in excess of the
maximum standing pressure indicated on the
heater nameplate, a separate positive shut-off
high pressure regulator must be added upstream
of the heater’s individual manual shut-off valve.
This regulator must be vented to the outside of the
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 the 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.

WARNING:
For roof mounting, the gas and electrical
connections must not penetrate the unit base
or mounting curb. Cambridge Air Solutions
recommends using pitch pockets or roof boots to
seal the penetrations.
2. Properly size the gas supply piping for the rated
capacity, per local codes, and/or the National Fuel
Gas Code, NFPA 54, ANSI Standard Z223.1 or the
CAN/CGA 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 access door from fully opening.
5. Install gas piping to the make-up air heater in
accordance with local codes or, in their absence, in
accordance with the National Fuel Gas Code, NFPA
54, ANSI Standard Z223.1, or the CAN/CGA B149
Installation Codes.
IMPORTANT
A 1/8" NPT tap is supplied with the heater for
measuring the gas supply pressure. The tap
is shipped with the low gas pressure shut-off
valve. The valve assembly is shipped loose
and tie wrapped to the gas train, to be field
installed. If the gas supply pressure exceeds
that indicated on the nameplate, the installer
must install a 1/8" NPT tap and high pressure
manual shut-off valve upstream of the high gas
pressure regulator.
IMPORTANT
An adequate sediment trap must be installed
prior to all gas controls for the heater and as
close to the gas inlet connection of the heater
as practical.
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. Check for leaks in the supply piping system. Use
liquid gas leak detector. Do NOT use flame.

CAUTION:
If the test pressure is in excess of 1/2 PSIG (3.5
KPA), the heater and its manual shut-off valve must
be disconnected from the gas supply system during
pressure testing. Failure to comply will void the
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 shut-off valve
during pressure testing.
 CAUTION:
Do not attempt to start the
make-up air heater at this time.
Premature start-up can result in damage to the
equipment and components.
INSTALLATION INSTRUCTIONS
GAS PIPING