What shuts off gas valve when no pilot light is present?

If the pilot goes out, no gas will flow into the valve. The only difference between the pilot safety switch and the combination gas valve is that the pilot safety switch is shutting the gas off electrically, and the thermocouple in the gas valve is shutting the gas off mechanically.

How to fix pilot light on gas furnace that is not hot?

Turn off the gas flowing to the furnace using the shutoff valve. Let your furnace cool down for 30 minutes. This needs to be done so it is not hot and is safe to open. Open the cover that covers the pilot light and visually inspect inside. Step 2 – Visually Inspect The Thermocouple For Alignment And Bends:

How can I tell if my gas valve is working?

Write down where the wires connect to the valve so you can reattach them later. Turn the test control on the multimeter to “mV,” which stands for millivolt. Hold each tester wand on the multimeter to one of the terminals on the gas valve. A normal reading will be in the range of 145 to 195 millivolts.

What to do if your boiler gas valve is stuck?

Call a boiler repair company and turn off your appliance. The problem here, is the gas valve might still be stuck open. If you can smell gas, it’s wise to turn off your gas at the mains. The mains gas lever is usually located next to your gas meter (it’s most likely yellow).

How do you test a furnace gas valve?

Pull the wires off the gas valve terminals. Each wire is connected to a push-on clip that slides off the terminal. Write down where the wires connect to the valve so you can reattach them later. Turn the test control on the multimeter to “mV,” which stands for millivolt.

When to replace the pilot safety unit or combination gas valve?

When replacing a pilot safety unit or a combination gas valve, always replace the thermocouple. If you do not have a thermocouple tester or millivolt meter, replace the thermocouple; if the pilot still will not stay lit, replace the pilot safety unit or combination gas valve.

What to do if gas is present at the gas valve?

Remove the pilot tube at the gas valve and depress the button. If gas is present at the gas valve and not at the pilot, check the pilot tube and pilot assembly orifice for blockages; clean or replace as necessary. The pilot stays lit. Check the thermocouple for lint or pet hair; clean if necessary.

How is the maintenance of a pilot valve?

During the valve installation, it should be smoothly lifted into position by using the lift eyes. The gasket must be checked and the nuts and studs must be lubricated. The valve must be properly set on the nozzle and the flanges. The maintenance of this valve is not a problem because it won’t give much trouble.

Why is there no reverse flow in a pilot valve?

There won’t be any reverse flow because the fluid pressure will close the poppet. In order to allow the reverse flow, then pilot pressure must be provided to the pilot port. The pilot-operated relief valves are used for emergency relief functions like the overpressure.