The blower on my gas furnace has been running without shutting off, even though I've lowered the temp on my thermostat, switched to off, checked to make sure fan is off.

I checked the thermostat, seemed to be connected correctly. Tried to install a new one, but problem persists.

Any suggestions on what else I might try would be appreciated. Thanks!!

 

The are a few different types of fan controls depending on model, age, and brand. One type has a temperature sensor and turns the fan on when it senses that the furnace is hot. They can stick when they get old. There is a type that is a time delay. It waits 30 or so seconds after the burner starts and then starts the fan, it waits 60 or more seconds after the flame stops to stop the fan. Those can fail in the on position too. It isn't an emergency repair but you don't need the fan running 24/7.

It is probably not the thermostat so don't spend too much time working on that. Unless you are pretty handy with electrical stuff, you will probably end up calling someone in to repair it.

 

Did you try and hit the furnace hard on its side with your hand. This works lots of times when a relay is stuck on or a fan control is stuck. Im like Ken I just dont know why people run out and get a new tstat and try and put it on. When the furnace or AC dont work. lets start and fine out what dont work are caused it not to work first. ED