Goodman GMV95

[salvemi7]

I aquired this furnace used and had it installed this year. Ther fan only runs for about 20 second and then shuts down. The fan limit control is showing that the tempeture drops very fast. I have had a man from my propane company look at it and he said it's drawing too much cold air but there is no ducting outdoor or in the crawlspace so I do not understand where the cold air is coming from. I was thinking that possibly it would be alright this way until now that the very cold weather has come(below 10 degrees). Yesterday I came home to a 50 degree house after about 8 hour of the furnace alone without woodstove.

I notice in an instruction manual I read online that this unit may need a two stage thermost, I think mine is single stage. Could that be a problem?

[Tech23]

Welcome, I see you have already started a thread on this topic in general area...so I will just say hello and glad to have you join us.

[oregonhvac]

Hello and welcome! Your furnace will only work with a single stage thermostat for heat mode. It's time to call for help! Your furnace needs to be set up properly to work right and be safe. You should call your local heating contractor for a service call.
Good luck!

[smstooge]

not always some of the goodman furnaces will run on first stage for a while and then after a time delay switch to second stage depending on a the model. Is that furnace set up that way u will have to check the manual to see. If it tells you that that model needs a second stage thermostat then that could be part of your problem. But fot the fan to shut off that early it doesnt seem right next time your down there put a thermometer in the return air coming back to the furnace it should only be 10-15 degrees difference at the most from your indoor temp. Normally its only something like 5-10 but if it is extreme then you have air leaking into you duct somewhere were the air is not tempered.

[salvemi7]

I was wrong on the model it is a GU050-2--The professionals are on the way. You guys were a great help but I know when to walk away and let the pro's do it. Thanks for all the help on theis thread and the other. You are awsome.