It was my understanding that the aqua stat setting determined WHEN the fan blower would start heating the room and the thermostat determines when the fan motor shuts off once satisfying the set temperature.

I had an air handler replaced this summer. Immediately during the start of heating season I noticed just to bump the temp 1-2 degrees that the fan would run for 45 minutes or so. If I lowered the temperature setting to meet the current room temp, it would still run for 30 minutes or so. I can understand a few minutes, but 20-30 minutes ???

I called the company back and they said the aqua stat was set to 100 and that it should have been set to 120. OK. I agree from the stand point of having warmer air blow initially as opposed to cooler air. But it shouldn't affect the run time of the fan blower once the thermostat temperature is satisfied.

They came and said they adjusted the aqua stat to 120.

Now the unit is short cycling. It came on this am for about 2 minutes then shut down. 1 minute later it came on again. Then it ran for a while.

It's a variable speed Goodman. Variable via which terminal is wired in. It's controlled via a nest T stat.

Full disclosure. This is the identical set up with my previous Trane air handler which was a true variable speed. Never had an issue until after 19 years. The ECM was causing the blower motor to ramp up and down at times. Also the evap coil sprung a leak.

I have to call the company back. Any ideas so i don't go in blind ???