Raypak 2600401 Water Connections & System Piping, Gas Pressure Specifications, Type of, Inches WC

Gas Pressure Specifications

Type of	Inches WC		Regulator
Gas	Min.	Max.*	Setting
Natural	7.0	10.5	4.0
Propane	12.0	13.0	11.0

*Do not exceed maximum inlet gas pressure. The minimum value shown is for input adjustment.

Table H: Gas Pressure Specifications

Gas Pressure Regulator

The gas valve is provided with pressure taps to meas- ure gas pressure upstream of the gas valve and downstream which is the same as the manifold pres- sure.

The gas pressure regulator is preset and sealed at 4 in. WC for natural gas, and 11 in. WC for propane gas. Between the gas valve and the burners is a 1/8 in. pipe plug. The pressure at this point, taken with a manome- ter, should be about 3.7 in. WC natural gas and 10.5 in. WC propane gas. Lo NOx models should be 3.9 in. WC natural gas only. If an adjustment is needed, remove seal and turn adjustment screw clockwise to increase pressure or counter-clockwise to decrease pressure.

Water Connections & System Piping

The pipe size and fittings between the heater and the tank should be at least 1-1/2" for all models. The tank should be located as close to the heater as possible, as shown in Fig. 13 below.

Fig. 13: Heater with Storage Tank

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