Normal or Not? AC cycle with Heat

[Andyba20]

I’ve read Mike’s comments on the AC compressor cycling, and tend to agree that it shouldn’t cycle if performing correctly. However, I’ve noticed mine will cycle with the heat on (defrost). Is this a normal function? 

[Mopar1973Man]

1 hour ago, Andyba20 said:

I’ve read Mike’s comments on the AC compressor cycling, and tend to agree that it shouldn’t cycle if performing correctly. However, I’ve noticed mine will cycle with the heat on (defrost). Is this a normal function? 

 

Might be... Depends on the air temperature in the evaporator. As the intake air cools the lo side pressure will fall and cause the lo side switch to cycle in and out. If the outside air is near 35*F it will cycle. Below this typically is will not even start at all because now the lo side pressure will fall so far that prevents the A/C from starting. 

 

I would check the pressure just to be safe on a warm day. 

[Doubletrouble]

 I though most vehicle a/c cycled intermittently while in defrost mode to help remove moisture from inside the vehicle? Helps to keep the inside of the glass fog free on wet days.

[Andyba20]

Heck I don’t know...but it was definitely above 35 degrees outside. More like 50.  

[Mopar1973Man]

Should be pretty solid. Might cycle if super humid. Thats when the evaporator gets covered in ice.