I am tired of paying for service calls and a seems like a simple fix. I fix everything else but am not familiar with HVAC. Here is the problem again... in FL. when I turn the heat or air on, the fan kicks on and blows very strong, but the heat ot cold air coming out of the vents is minimal. is there some kind of relay that needs to be replaced? or what could be the problem.

thanks

Ron,

I'm not a HVAC guy, but I'm the kind of guy who tries to fix everything and this is one of those things that I'd try. I agree that it does sound like some basic component failure.

It seems that the thermostat is working because the fan starts up. I'm assuming there is only one set of wires leadin out to the heater and another set to the AC. More wires implies that the fan is controlled independently from the AC & heat and thus the thermostat could still be at the root of the problem.

The fact that you get no heat and no cool suggest some more basic control problem.

Before you go too deep, start with the basics, make sure the filter is clean and that the air intakes are not blocked.

Sorry I don't have any more info for you.