Last year I had a problem with my heater. When the thermostat was switched to "Heat" and the fan was switched to "Auto" the thermostat would click but not heated air ever started blowing out of the vents. However, when the fan was switched to "On" the system would blow out heated air. Obviously, when the area reached the selected temperature on the thermostat, the fan would continue to blow air out of the vents only it was unheated.
I called out an HVAC person who did something with the unit in the attic. They didn't replace anything and if I remember hearing them correctly, they did something with a sequencer, maybe reseated it.
So, I spent $150 for them to come out and do a very minimal job but it fixed the problem.....or so I thought.
The system started doing the same thing 2 days ago. The HVAC tech that came out last year stated it wouldn't hurt anything if I needed to run the fan in the "On" position to heat the area but I cannot help but think that it will hurt my electric bill hence my wallet and I don't really feel like calling him back out and blowing $150 or more to fix the the problem temporarily again.
Is this something I could fix via DIY or should I call another HVAC pro out to handle the situation.
Thanks for any and all advice.