Furnace repair----Gas valve

[Adam]

My furnace is not working. The pilot light is lite, but the burner does not kick in when I turn up the thermostat. I believe that it is the gas valve. I have concluded this because I cannot hear it click when I make the call for heat from the thermostat. I also have ruled out a faulty thermostat by disconnecting it and connecting the W wire and the R wire and bypassing the thermostat.

If it is the gas valve, is it something I can repair my self? If not what is a reasonable price for getting it repaired. I have noticed that the part sells for around $100. Thanks for any help!

[Tony Hwang]

Hi, Do you have control volt(24 Volt AC) going to valve when thermostat calls for heat? Easiest way to check is to remove thermostat cover and moving the temp up/down, look at the mercury switch, do you see little sparks? Maybe the transformer for 24V AC is gone bad. Tony

[mwlogs]

If your furnace is old enough to have a true pilot light, then it will have a thermo-couple similar to that found in a hot water tank. This keeps the main gas valve from opening if the pilot is out. Since it is constantly in the heat of the pilot flame, it will eventually burn up. When this happens, even if the pilot is lit it doesn't register and the burner won't ignite.

Look for this, if could be one that connects directly to the value, as in a hot water tank, or one that has an electric contact the breaks the circuit to the thermostat. Probably not difficult to replace.

[TURTLE]

This is Turtle.

Adam your thinking maybe good here but it is flawed with a bunch of things that still does not say it is a gas valve. You need to remove the two wires going to it and hold them away from anything that will short out to and put your volt meter on the two wires and see if you get 24 to 28 volts AC coming to it. If so it's your gas valve maybe. If not it is not the gas valve.

Pricing . Hey it can range a great deal from one part of the country to the other. A gas valve replacement depending on service rate and parts pricing in your area. It could run between $185.00 to $500.00. I get for regular customer to change the gas valves between $185.00 to $245.00 [ not a rare type ] really depending on the type gas valve they have. Pricing without knowing the area or the gas valve type is very hard to do for I have paid Wholesale for a Carrier auto ignition type gas valve $251.00 and is suppose to sell it at a 30% mark up to warrenty it for 1 year. This would put the gas valve over $300.00 price to you and no labor yet.

Another point here. The price of gas valves is like what is the price of a new car but then they say what kind of car do you want. All gas valve are not the same and prices vary vastly.

TURTLE

[rednelb]

I had the same problem, I changed the thermocouple and that didn't help, checked everything and it seemed ok. Turned out to be a pressure switch that was *stuck* or something.

[Joe Fabeitz]

Huh? The TURTLE has struck...again.

[Stormin Mormon]

Sounds like a good moment to call a repair guy. The risk is great -- if you hook something up wrong, it could be a mess. Besides, it sounds like you're not sure it's the gas valve. Could be the power supply or the circuit board or.... why change a valve and find it's something else?