9.Install a coupling, nipple, union and sediment trap onto the right-hand end of the main gas line and then install the gas line, making sure that a manu- al shut-off valve has been installed within 10 ft of the heater.

10.Replace the left and right front panels on the heater.

Gas Supply Pressure

A minimum of 5.0 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 11.0 in. WC and a maximum of 13.0 in. WC is required for propane gas. The gas pressure regulator(s) supplied on the heater is for low-pressure service. If upstream pressure exceeds 14.0 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 for the combined load.

The gas valve pressure regulator(s) on the heater are nominally preset at 3.5 in. WC for natural gas, and

10.5in. WC for propane gas. 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 adjust- ment is needed, remove the adjustment screw cover and turn the adjustment screw clockwise to increase pressure or counter-clockwise to lower pressure.

Electrical Power Connections

Installations must follow these codes:

National Electrical Code and any other national, state, provincial or local codes or regulations hav- ing jurisdiction.

Safety wiring must be NEC Class 1.

Heater must be electrically grounded as required by the NEC.

In Canada, CSA C22. 1 C.E.C. Part 1.

The heater is wired for 120 VAC, <12 amps. The volt- age is indicated on the tie-in leads. Consult the wiring diagram shipped with the heater in the instruction packet. The remote tank control stat, thermostat, or electronic heater control (as applicable) may be con- nected to the stage selector terminal (See wiring diagram). 24 VAC is supplied to this connection through the heater transformer. DO NOT attach any voltage to the stage selector terminals. Before starting the heater check to ensure proper voltage to the heater and pump.

Install a separate disconnect means for each load. Use appropriately sized wire as defined by NEC, CSA and/or local code. All primary wiring should be 125% of minimum rating.

If any of the original wire as supplied with the heater must be replaced, it must be replaced with 105°C wire or its equivalent.

Field-Connected Controllers

It is strongly recommended that all individually-pow- ered control modules and the heater should be supplied from the same power source.

NOTE: Field-supplied isolation relays should be installed when field-connected controllers are mounted more than 50 equivalent feet (18 Ga) from heater.

Check the Power Source

WARNING: Using a multi-meter, check the following voltages at the terminal block inside the unit. Make sure proper polarity is followed and house ground is proven. (See Fig. 18.)

Fig. 17: Gas Valves

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Raypak 992B-1262B Electrical Power Connections, Gas Supply Pressure, Field-Connected Controllers, Check the Power Source