Raypak 122, Installation & Operating Instructions Manual

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18
Fig. 12: Sediment Trap Orientation
SUPPLIED
BY OTHERS
EXTENTS OF
UNIT ENCLOSURE
GAS
FLOW
TO BURNERS
SEDIMENT TRAP
MANUAL
SHUT OFF
VALVE
SUPPLIED
BY OTHERS
EXTENTS OF
UNIT ENCLOSURE
GAS
FLOW
TO BURNERS
UNION
SEDIMENT
TRAP
MANUAL
SHUT OFF
VALVE
Gas Supply Connection Gas Supply Pressure
A minimum of 7 in. WC and a maximum of 10.5 in. WC
upstream gas pressure is required under load and no
load conditions for natural gas. A minimum of 11 in.
WC and a maximum of 13 in. WC is required for
propane gas. The gas pressure regulator supplied on
the heater is for low pressure service. If upstream
pressure exceeds 14 in. WC, an intermediate gas
pressure regulator, of the lockup type, must be
installed.
When connecting additional gas utilization equipment
to the gas piping system, the existing piping must be
checked to determine if it has adequate capacity.
Gas Pressure Regulator
The gas valve pressure regulator(s) on the heater are
nominally preset at 3.5 in. WC for natural gas, and
10.5 in. WC for propane gas manifold pressure. The
pressure at the gas valve outlet tap, measured with a
manometer,while in operation should be 3.5 ± 0.1 in.
WC for natural gas and 10.5 in. ± 0.1 in. WC for
propane gas. If an adjustment is needed, turn the
adjustment screw clockwise to increase pressure or
counter-clockwise to decrease pressure.
CAUTION: The heater and its manual shutoff valve
must be disconnected from the gas supply during
any pressure testing of the gas supply system at test
pressures in excess of 1/2 PSIG (3.45 kPa). The
heater must be isolated from the gas supply piping
system by closing the manual shutoff valve during
any pressure testing of the gas supply piping system
at test pressures equal to or less than 1/2 PSIG.
Relieve test pressure in the gas supply line before
reconnecting the heater and its manual shut off valve
to the gas supply line. FAILURE TO FOLLOW THIS
PROCEDURE MAY DAMAGE THE GAS VALVES.
Over pressurized gas valves are not covered by
warranty. The heater and its gas connections shall
be leak tested before placing the appliance in
operation. Use soapy water for leak test: DO NOT
use open flame.
CAUTION: Do not use Teflon tape on gas line pipe
thread. A pipe compound rated for use with gas
systems is recommended. Apply sparingly only on
male pipe ends.
CAUTION: Support gas supply piping with
hangers, not by the heater or its accessories. Ensure
the gas piping is protected from physical damage
and freezing where required.