Goodman Furnace Gas Valve Not Opening

[Cameron]

replying to Old retired sparky local#176, Cameron wrote: Hi, I really need some help! Having the same problem as described in the thread. The furnace ignites but the burners will not work. Had the gas valve replaced and it worked for a month. Then same issue. Replaced the gas valve again and good for a month. Now again same issue. Tried to squeeze the black hoses manually and no issues. I've had 2 very good techs come and they only fixed temporarily. Please if anyone can help, I'd be very very thankful. This is painfully frustrating!

Ps. It's a Goodman 95% gmh950703baxf.

[Cameron]

replying to Old retired sparky local#176, Cameron wrote: Hi, I really need some help! Having the same problem as described in the thread. The furnace ignites but the burners will not work. Had the gas valve replaced and it worked for a month. Then same issue. Replaced the gas valve again and good for a month. Now again same issue. Tried to squeeze the black hoses manually and no issues. I've had 2 very good techs come and they only fixed temporarily. Please if anyone can help, I'd be very very thankful. This is painfully frustrating!

Ps. It's a Goodman 95% gmh950703baxf.

[trader_4]

Put a meter on the gas valve and verify that it has ~24V AC on it when it's supposed to open. It it does and gas doesn't flow, then it's either the valve or a problem with the gas supply. If there isn't 24V there, then it's a problem with the control board, a sensor or wiring and connection. Most likely not a sensor, because AFAIK furnaces won't light up the igniter if a sensor is saying no-go. If the valve is kaput again, has anyone investigated the failed ones to figure out why they failed? Any chance there is debris in the gas lines? Does it have a sediment trap near where it enters the furnace? A sediment trap is a short piece of pipe with a capped end that goes down off a tee at the appliance. It's there to catch any crap instead of it going into the appliance.

[trader_4]

IDK how that type works, it's a good question. I would not call that a two stage valve though. Two stage furnaces have a high and low heat output capability and by calling it two stages it can confuse it with that. What you're talking about is a type of intermittent pilot light, where it lights a pilot light, then turns on the gas. Mine I don't think does that, it has a hot surface igniter and I think it just gets that hot, then turns on the burner gas.

Perhaps the OP has a failure of the full voltage being

[agvanry]

I had the same issue but the air hose coming out of the ducting in my furnace was clogged after blowing in it a few times the chunk finally came out, thanks to this post, was looking for hours thanks

[Richard Y]

Thank you to Bubba for this solution! Even the heating company tech couldn't solve the problem... Still solving the issue in 2020!!