An AC system can fast cycle for a number of reasons. The most common is low refrigerant but it can also be too much refrigerant, a restriction in the system or a faulty switch.
My suggestion is that you have the system completely and have it recharged with the proper amount of refrigerant. If the refrigerant is low, then you will need to get it leak checked or it's going to happen again.
Thursday, September 2nd, 2010 AT 11:53 AM