Compressor takes too long to come on
I have a problem with my G.E. 2HP window type air conditioner. It used to run fine around 6 months ago, but when I moved to another house, the unit was left unused in a corner of my garage until recently. The unit's relatively new (less than 18 months old to date) and wasn't used very often.
Now, when its turned on initially, the compressor comes online immediately as soon as I select any of the cooling settings. It runs normally for around 5 minutes or so then, the compressor cuts out like it would when it has reached the temp setting on the thermostat even if it isn't even anywhere near that setting, and regardless of whether the thermostat's turned all the way up, down, or anywhere in between. The blower fan runs normally all the time though.
After it cuts out, it takes much longer than it should before the compressor comes on again, resulting in wild temperature swings.
I'm in the Philippines, and at present, the normal ambient temperature here runs at about 92-102 deg F. I have the aircon's thermostat set to hold at around 85-88 degrees, give or take a couple. With the compressor acting up like I described above, the temperature in my room swings from a low of around 87 degrees to a high of almost a hundred.
There are no loose wiring connections, and the caps are fine. I suspected the thermostat to be the culprit but a simple continuity test with a multimeter showed it was working fine, or at least it had continuity. The switches are all fine too. The system has never been repaired, refilled with refrigerant, nor has any of the tubing been opened since it came out of the factory, so I guess that rules out contaminated refrigerant. The hot air that comes out the back when the compressor's running seems normal too. The cooling coils are clean, front and back. No rattling, humming, hissing or any unusual sound or vibration can be heard or felt. Voltage at the outlet where the unit's plugged in is also nominal.
Also, when the compressor's running, I noticed that there are around 6 (3 pairs, one pair at the top, one pair around the middle and the third pair near the bottom) of the pipes going to the cooling coils in front of the AC had a (very) thin layer of frost that went away as soon as the compressor cuts out. Does that layer of frost mean anything?
I hope someone can give me advice on what to check, or maybe his opinion on what could be wrong with this thing. Any advice, suggestion, opinion, theory, or even an educated guess would be very much appreciated...