Heat is not constant. Why won't fan turn on? - Heating & Cooling

Sounds like a bad motor module.

at the thermostat you should have a setting for fan "ON" that should do it

OverheatingWhen the CPU overheats then it will shut down (i.e. thermaloverload) and won't boot up again until it has cooled down. If this is theproblem is not fixed then the CPU will eventually fail.
A faulty fan causes the problem or the fan and heat sink assembly are cloggedwith dust.
Check the CPU fan to see if it spins freely, if not replace the fan.
If the fan and heat sink is clogged with dust the remove the dust and make surethe vents are clear and dust free. Use a small brush and can of compressed airto do this.

Could be starting capacitor on fan motor. If equipped. Trained electrician should be consulted in this case.

When the CPU overheats then it will shutdown (i.e. thermal overload) and won't boot up again until it has cooled down.If this is the problem is not fixed then the CPU will eventually fail.
A faulty fan causes this problem or the fan and heat sink assembly are cloggedwith dust.
Check the CPU fan to see if it spins freely, if not replace the fan. If the fan and heat sink is clogged withdust the remove the dust and make sure the vents are clear and dust free. Use acan of compressed air to do this.

Mine has two switches one says cool - off - heat, the other says fan on - fan auto. For heat I set the first to heat and the second to auto. This puts everything in to heat mode and the fan runs from the furnace control now not constantly. Hope this helps you out.

As long as you have the cells in the correct direction, the air flow direction you should be O.K. If you have a way of turning on a constant fan that will help dry them. I would shut the power button off to the electric air cleaner and run a constant fan for 24 hours. After that, turn the power on and the constant fan off. Turn up the heat and see if it works.

suggest starting with thermostat replacement only because it sounds as if the fan/heating control has constant power.
good luck

Dave

I suspect you could have a heat sink fan not working remove side of case and when you turn computer on check fans heat sink and video card are working
With computer OFF
remove heat sink fan and check that the heat sink is not clogged up with fluff and dirt.
I regularly clean both fan and heat sink every 2 months also check the fan in power unit and blow it out