Air conditioner doesn't other cut on.? My central nouns unit will not other cut on when the room...

My central nouns unit will not other cut on when the room temperature rises above the heat set on the thermostat. If I turn the system off at the thermostat and hang about five to ten seconds and turn the system rear on, it will work properly for a period of time. At some point, I will own to repeat the above steps. Do you think my thermostat wishes to be replaced or is this a more serious problem? My system is about 10 - 15 years elderly and I have have it serviced twice in former times three weeks. Once, it lost its charge and needed freon. The other time the drain in the element became clogged and have to be cleaned out.
I own a electric wiring problem?
Answers:    You may have a unpromising thermostat. For a step by step troubleshooting guide, check out the air conditioner page at my source.
Frost surrounded by the INSIDE of the fanlight?
Take the cover stale of the thermostat and see if it has a mercury bulb within it.If it does the stat must be level.It could enjoy gotten loose over the years.But stats do wear out.