Raypak 302B, 902B manual Gas Supply Connection

Gas Supply

DANGER: Make sure the gas on which the heater will operate is the same type as specified on the heater’s rating plate.

Gas piping must have a sediment trap ahead of the heater gas controls, and a manual shut-off valve lo- cated outside the heater jacket. It is recommended that a union be installed in the gas supply piping adja- cent to the heater for servicing. A pounds-to-inches regulator must be installed to reduce the gas supply pressure to a maximum of 10.5 in. WC for natural gas and 13.0 in. WC for propane gas. The regulator should be placed a minimum distance of 10 times the pipe diameter up-stream of the heater gas controls. Refer to Table K for maximum pipe lengths.

Gas Supply Connection

CAUTION: The heater must be disconnected from the gas supply during any pressure testing of the gas supply system at test pressures in excess of 1/2 psi (3.45 kPa).

The heater must be isolated from the gas supply pip- ing system by closing the manual shut-off valve during any pressure testing of the gas supply piping system

Fig. 16: Gas Supply Connection

at test pressures equal to or less than 1/2 psi (3.45 kPa). Relieve test pressure in the gas supply line prior to 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 cov- ered 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 an open flame.

CAUTION: Do not use Teflon tape on gas line pipe thread. A pipe compound rated for use with natural and propane gases is recommended. Apply sparingly only on male pipe ends, leaving the two end threads bare.

CAUTION: Support gas supply piping with hangers, not by the heater or its accessories. Make sure the gas piping is protected from physical damage and freezing, where required.

Reversing Gas Supply Connection

Reversing the standard fuel connection from the left- hand to the right-hand side is a simple field operation.

1.Disconnect all electrical power from the heater (if applicable).

2.Disconnect the main gas pipe from the heater (if applicable).

3.Remove the left and right front panels from the heater.

4.Locate the main gas line that traverses across the heater above the manifold risers.

5.Remove the pipe cap from the right-hand end of the main gas line.

Model

No.

3/4"

1”

1-1/4”

1-1/2”

2”

2-1/2”

N

P

N

P

N

P

N

P

N

P

N

P

302B	15	25	35	85	150	380	360	--	--	--	--	--
402B	--	15	25	60	100	260	250	--	--	--	--	--
502B	--	--	--	--	65	150	130	360	500	--	--	--
652B	--	--	--	--	45	100	95	250	340	--	--	--
752B	--	--	--	--	35	80	75	180	260	600	--	--
902B	--	--	--	--	20	45	45	110	150	360	400	--

Natural gas – 1,000 BTU per ft3, .60 specific gravity at 0.5 in. WC pressure drop Propane gas – 2,500 BTU per ft3, 1.53 specific gravity at 0.6 in. WC pressure drop

Table K: Maximum Equivalent Pipe Length

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