Weil-McLain LGB-4 V Verification testing, Manual test firing valve, Leak test automatic gas valve

LGB-4 & 5 • Control Supplement • UCS • Nat. Gas

V Verification testing

Manual test firing valve

Verify boiler control sequence

Leak test automatic gas valve

Before starting boiler for the first time and at least annually (during annual inspection and start-up), follow the procedures below to verify boiler controls are operating correctly and that automatic gas valve properly shuts off gas flow. Failure to verify boiler operation could result in severe personal injury, death or substantial property damage.

This boiler is equipped with a manual test firing valve — the manual gas valve piped between the gas manifold and the automatic gas valve. Closing the manual test firing valve allows verification of proper boiler operation without allowing gas flow to the manifold and allows leak testing of the automatic gas valve. Follow the procedures below.

1.Follow the Operating Instructions in this Supplement to start the boiler, but do not open the manual test firing valve. Open all other manual gas valves as instructed. Leave the manual test firing valve closed.

2.The automatic pilot burner should light.

3.After the pilot lights, the boiler controls should activate the automatic gas valve. Use a voltmeter to verify voltage to automatic valve.

4.With no gas flow to the manifold, the boiler ignition controls should turn off the automatic gas valve after main flame ignition trial. Use a voltmeter to verify voltage to automatic valve is turned off.

1.Close manual test firing valve.

2.Open the service valve. Press down and turn automatic gas valve knob (or lever) to ON.

3.Install a hose barb into a pressure tap downstream of the automatic gas valve. Allow any accumulated gas in the line to vent off. Then connect a U-tube manometer. If the valve seals properly, there should be no gas pressure present. Remove manometer and hose barb and replace pipe plug in pressure tap.

4.Remove the manometer and plug any open pressure taps.

5.Follow Operating Instructions to place boiler in service.

Replace any defective components. Do not attempt to operate boiler or leave boiler in operation if any component is found to be defective or to operate incorrectly. Failure to comply could result in severe personal injury, death, or substantial property damage.

Part Number 550-141-918/0304 7