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Blower in Attic not running

I have a blower / heating unit in my attic with the compressor units outside.  Recently, both fan units in the attic went out.  The circuit breaker is live, and the electrical outlets in the attic servicing both units are hot.  My problem is this:  When I turn on the thermostat to the AC, the outside compressor unit runs.  However, the blower unit in the attic does not.  It does not matter whether I set the thermostat to heating or cooling, the blower unit in the attic does not run.
Any suggestions?
Thanks in advance

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Re: Blower in Attic not running

Inside unit has fan control relay , either on control board or can be separate ,except for the 24 volt transformer and the t-stat the units operate separately concentrate totally on the inside unit this is where the problem lies

Posted on Nov 08, 2008

Re: Blower in Attic not running

It sounds like you may have a gas furnace in your attic. Solutions sound of 3. Bad thermostat not calling for fan, bad circuit board in furnace or bad capacitor and or motor in furnace.

Posted on Oct 25, 2007

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Re: Blower in Attic not running

Check the access panel for proper fit. Occasionally the panel could shift causing the blower door safety switch to open causing the attic unit not run.
While you are up there, inspect and clean/replace the air filter.
Make sure there is power going to the control in the attic unit by using an inexpensive voltage pencil. This is a simple tool that you can use to test outlets with also, so all is not lost if you purchase one. All it is, is a probe you hold next to wires and hold down a button. If voltage is present, it will glow or buzz. They cost less than $15 at a hardware store.
Hold the probe close to the wires inside the attic unit and tape the door closed. If you have power, it will sense it. If not, call a technician.

Posted on Oct 24, 2007

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