How do you test a millivolt gas valve?

Quote from the video:
Quote from Youtube video: Lower I would have to turn clockwise. And to adjust the flame higher I would have to turn it counterclockwise.

How do I know if my furnace gas valve is bad?





Here are some signs that indicate your furnace has a bad gas valve.

  1. A Gas Leak. This is a major indicator that something could be wrong with the gas valve in your furnace. …
  2. A Total Shutdown of the Furnace. …
  3. A Flooded Furnace. …
  4. Get Expert Services.


How do you test a gas furnace control valve?

Quote from the video:
Quote from Youtube video: Because it's two stays that means there are two valves in the gas valve. And. So you have to check the correct one okay the easiest way to do this checking is you don't get too.

How many millivolts do you need to open a gas valve?

A new 750 should put out 750 if pilot flame is proper. Under load 550 is good. Alot of valves require min. 350mv to open burner.

How do you test a gas valve with a multimeter?





Quote from the video:
Quote from Youtube video: Check your leads and place them from top to bottom pin. And across dolls you should read a measurable resistance stay on the top pin go to the next pin up again.

How does a millivolt gas valve work?

Millivolt Gas Valve



This type of valve makes use of a standing pilot that continuously burns to heat a device, either a thermocouple or thermopile, which then produces a small amount of electricity – less than a single volt, hence “milli”-volt.

What causes a furnace gas valve to fail?

The valve itself may have simply worn out or may be damaged due to basement seepage or submersion. Alternately, one of the electronic gas ignition components or a glitch in the safety circuit may be to blame. If your furnace has a standing pilot light, the thermocouple could be worn out.

How do you free up a stuck gas valve?

Heres how; First, turn off the gas in the house so you don’t blow yourself up or cause a disaster, loosen the bottom nut, tap the bottom of the plug upward to loosen the tapered plug, remove the tapered plug, lubricate with a special gas valve grease , and re-install the plug, job done.

How do you test a gas valve solenoid?



Quote from the video:
Quote from Youtube video: The coil should indicate a resistance between ohms. Now keeping the probe on the common terminal move the other probe to the third terminal.

How do you test a millivolt on a thermocouple?

Turn the appliance on and place a crocodile clip from the multimeter to the side of the thermocouple. Attach the other crocodile clip on the screw that extends out of the side of the adapter. The reading should be within 12 millivolts and 15 millivolts.

How many millivolts should a thermopile read?

A healthy thermopile in an open circuit test will read between 650 to 850 millivolts or somewhere in between. If the open-circuit test reads below 400 millivolts, then the thermopile likely requires service or replacement.

How do you test a millivolt thermopile?



Quote from the video:
Quote from Youtube video: You'll know the pilot is lit as the voltage will start to climb. Continue to hold down the gas controls thermostat knob until maximum voltage is reached.

How many ohms should a gas valve have?

Test the coils with an ohmmeter with the wires disconnected (you only need to disconnect one wire on each coil) and you should get around 40-60 Ohms resistance at the two leads of each coil. If the meter reads much lower or much higher then the coil is bad and needs to be replaced.

What does MV and PV stand for on gas valve?

Some valves have more than two wires controlling the valve. These are usually a PV (pilot valve), an MV (main valve), and a COMMON wire.

How do you wire a millivolt gas valve?

Quote from the video:
Quote from Youtube video: Actually wired into the gas valve and it's wired into the pilot solenoid valve. So we have our power coming into the tht p on the red wire right here and that gets connected to this wire.

How many millivolts should a thermocouple produce?



A single thermocouple (C Type) is used for a standing pilot system and generally produces around 30 millivolts. This voltage is used by the gas valve to keep the pilot valve solenoid internal to the main gas valve open.

How does furnace gas valve work?

The furnace gas valve operates by electromagnets. The primary valve — also known as the safety valve — supplies gas to the pilot light. The second valve — also known as the main valve — allows gas to flow to the burner trays. The thermocouple (or thermopile) generates the power holds the safety valve open.

What is a millivolt switch?

This light switch is specifically designed to control a gas log set that utilizes a millivolt pilot control. This pilot system has a small flame that generates power for the unit’s gas valve to operate. As a result, they do not require outside power to operate and can be used in the event of a power outage.

How do you clean a thermopile?

To quickly clean your thermopile, turn off the gas supply. With the help of a stainless steel brush and fine-grit sandpaper, you can scrub off as much piled up soot as possible.

How do you test a gas fireplace valve?



Quote from the video:
Quote from Youtube video: Completely light the pilot. Turn the gas knob to the on position. Turn the burner on in a high position check the pressure and record it shut the burner off.