Fan timeout delay for AC operation

[Garyl53]

Hi.
What is the recommeded fan timeout delay when running AC this time of year. Should it be set for zero?
Thanks,
Gary

[HVACJOEK]

3 to 5 minutes, I usally set it at 3 minutes. :cool:

[Garyl53]

Thanks, I finally found an older thread that discusses this in depth.
Gary

[jerrod6]

Hi.
What is the recommeded fan timeout delay when running AC this time of year. Should it be set for zero?
Thanks,
Gary

What is this timeout used for?

[Garyl53]

On most furnaces there is a set of switches allowing you to select how long the fan will run after the heating or cooling cycle ends. In heating mode the heat exchanger is still hot at the point that the cycle ends. The delay allows the system to circulate the heat still remaining for the selected amount of time. In cooling mode the A-coil is still cold at the point the cycle ends so the time delay allows the system to circulate the air until the coil starts to warm. In cooling mode there is a concern that if the coil warms and their is still a lot of condensation on it then it will start to increase the humidity in the home since it is blowing air across the wet coil. The delay is difficult to estimate since it depends on the humidity level in the home, the amount of condensation left on the coil, and how fast it is draining out of the A-coil condensation pan. I am in a dry climate so I think 2 or 3 minutes will be fine but if you are in a very humid climate then you may want to select a very low number of seconds or even zero seconds. I am not a pro at all so anyone please correct my explanation if incorrect.
G

[jerrod6]

On most furnaces there is a set of switches allowing you to select how long the fan will run after the heating or cooling cycle ends. In heating mode the heat exchanger is still hot at the point that the cycle ends. The delay allows the system to circulate the heat still remaining for the selected amount of time. In cooling mode the A-coil is still cold at the point the cycle ends so the time delay allows the system to circulate the air until the coil starts to warm. In cooling mode there is a concern that if the coil warms and their is still a lot of condensation on it then it will start to increase the humidity in the home since it is blowing air across the wet coil. The delay is difficult to estimate since it depends on the humidity level in the home, the amount of condensation left on the coil, and how fast it is draining out of the A-coil condensation pan. I am in a dry climate so I think 2 or 3 minutes will be fine but if you are in a very humid climate then you may want to select a very low number of seconds or even zero seconds. I am not a pro at all so anyone please correct my explanation if incorrect.
G


Got it. I just didn't think of it as a timeout