Hello,

My AC unit will not run on. I have power a the stat i.e. when I turn it to cool the furnace fan motor comes on. When I walk out to the unit and depress the contactor the unit fires up and the compressor comes on. If I let go the unit goes off. I don not hasve a vole meter to check if I have 24v go to the contactor any ideas?

That's some good basic diagnosis, but unfortunately you need a voltmeter from here on in to see what's not getting power.

Is this a ac only or a heatpump?