Author Topic: Changing gas valve on furnace  (Read 758 times)


  • Bristles
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  • Posts: 250
Changing gas valve on furnace
« on: December 22, 2017, 04:57:28 PM »
Hello all,

The HVAC guy told me that the gas valve in my old furnace no longer works and that I need to replace it.

He quoted me $560 to replace the gas valve. Is this a job I could do as a somewhat handy man or should I get the HVAC company to do it. Also is the $560 resonable, they are quoting around $360 for the part and $170 for labor.


  • Handlebar Stache
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  • Posts: 1826
Changing gas valve on furnace
« Reply #1 on: December 23, 2017, 07:36:46 AM »
If you are bored and want to blow up your house...go for it. Do you realize that licensed tradespersons have a license for a reason? They are experts and know what they are doing. If you have to ask if you can do this, you better NOT do it! Gas in nothing to play with. A house in my town blew to smithereens a few years back. It was gas related. One person killed and another hospitalized for a long time.

Jon Bon

  • Pencil Stache
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  • Posts: 593
  • Location: Midwest
Re: Changing gas valve on furnace
« Reply #2 on: December 23, 2017, 11:20:13 AM »
I guess to answer we probably need more information.

If the valve next to the furnace was bad, I would say 100% DIY.  In the furance I guess that depends on alot of factors juding by the bid it sounds like it mig require removal of other components/pipes?

A lot of the issue is going to be getting the correct part, there are lots of different brands and types and lots of different manufactures. So it might be worth to to use a professional just for that.

However in general you should not be afraid of working with gas, its really not nearly as scary as it sounds. First step is always use pipe dope or tape on all threaded connections (unless it says not too!) The second is to spray soapy water on all the joints and see if it bubbles. A simple repair like replacing a valve or adding additional pipage can be done by nearly anyone as long as your are diligent and check for leaks.

But back to your furnace, really I would like to know more about the type of part and where it is. I am not HVAC repairman, but what valve costs $360? IMO about $500 is when I start to think about replacing the unit. I have a good hvac guy and can get me a new unit for around $2,000 so YMMV.

I of course defer to paddedhat whenever he finishes his Christmas dinner he should probably be around......


  • 5 O'Clock Shadow
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  • Posts: 73
Re: Changing gas valve on furnace
« Reply #3 on: December 27, 2017, 02:31:37 PM »
Of course gas is dangerous and should be treated with caution.  That being said, the gas valve is a pretty simple swap and is threaded on both connections.  Gas rated teflon tape and or teflon dope will be necessary,  +1 to soap spraying all connections to ensure there are no leaks. The gas valve operates via electrical signal from the mother board, ours has two connections, reconnect those and use a manometer for setting correct manifold (gas) pressure- that's the complexity of the replacement. You can find a TON of info & videos on the topic.  If they sound doable, it is.  If it still seems scary, then defer.

For price checking the quote from the HVAC guy (or informing your decision to DIY), you can get the model/serial number of your current gas valve and see what the part only price is.

To the poster who made a big deal about licensed HVAC technicians: 1) this is the DIY discussion forum, 2) You're on a site that regularly advocates having the wherewithal to LEARN THINGS YOURSELF (or did you miss where MMM replaced his own furnace?!), 3) I've met some idiots who are "licensed" in their trade.  Licensing seems to be more about rent seeking from the govt than true knowledge assessment these days.