Heat Pumps and Electric Heating - defrosting

The saga continues.....I was outside seeing my daughter off to the school bus when I heard the "whoosh nosie" went over to heat pump to observe..the fan blades stopped and it strated to run"hum"..it ran maybe 20 secs then stopped started again for 20 secs then stopped did in one more time then stopped...I also noticed the frosting on the coils was maybe odd three bands of frost..it 36 degrees when i type this..is my compressor short cycling....I also notice when I came back in the house...I heard the "click" from the t-stat..heard the pump come on...shortly thereafter heard a "whoosh"..it started in defrost mode?...:confused: :eek: Its a Copeland compressor on 2003 Armstrong Air(Allied) SHP10E24-A Heat Pump

Dear Sir, Damp and rainy weather at a temperature close to the freezing point will call for many small defrost even if little frost is present on the outside coil.Thats the way heat pump works.All the noise you hear is normal but annoying for some people.Good luck!

My heat pump is freezing over. It doesn't defrost like it is suppose to. It comes on and works but when the temperature is damp and cold it doesn't defrost itself. I don't hear the whoosh sound or see the steam that I used to hear when it defrost. It use to when it defrosts it would sit there and humm to defrost before it kicked in and started it would make a whoosh sound and start running. What is this? Could this be the defrost board outside? HELP.

dear desperate it probably needs a new defrost board. Be sure to run the test mode after you install the new board to check for any other problems.