Roberts Gorden UHA[X][S] 30 Gas Valve for Models UHAXS 60, Check Gas Rate, Pressure Switch

SECTION 10: OPERATION AND MAINTENANCE

Figure 18: Gas Valve for Models UHA[X][S] 60 - 125

END VIEW TOP VIEW

Regulator

½PSI C

IN

OFF

Gas Inlet

ON

Outlet

Pressure

Inlet Pressure

Description		Part Number
Gas Valve 60	- 125 NG	90032505
Gas Valve 60	- 125 LP	90032506

10.2.2Start-Up the Gas Valve (All Gases) 10.2.2.1 Check Burner Gas Pressure

1. Remove the plug in the outlet (burner) pressure test point and connect a pressure tap and a manometer.

2.With the burner firing, measure the pressure on the manometer. To adjust the burner pressure, remove the regulator cover from the valve and turn the regulator adjustment screw to set the required burner pressure as stated in the Technical Data Tables for the correct gas and model on Page 50, Section 15.3.

IMPORTANT: If the correct burner pressure cannot be reached, then check the inlet pressure to the valve with the burner firing. See Technical Data Tables on Page 50, Section 15.3 for inlet pressure requirement.

Do not continue to adjust the regulator if the pressure is not changing.

If the inlet pressure is too low to allow correct burner

pressure setting, then the gas inlet pressure must be corrected before completing the start-up.

Check Gas Rate

1.After burner pressure adjustment, allow the heater to operate for at least 15 minutes and then re-check settings. Adjust pressure setting if necessary.

2.Check gas flow rate at gas meter.

3.Turn off heater and electrical supply.

4.Remove the manometer and refit all covers to the valve and tighten the screw of the outlet pressure tap.

10.2.3 Pressure Switch

The pressure switch is factory pre-set for each model and is not adjustable.

10.2.4 Turning Off the Heater

Set the thermostat to the "OFF" position or lowest setting and the main burner will stop.

The fan will continue to run for 90 seconds.

Do not use a disconnect switch for control of heater. Disconnect switch will turn off the fan.

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