I just had technician check out my central A/C unit. He replaced a fuse and some wiring in the furnace and had the A/C working. He turned it off and on a few times to make sure it was working properly. After a couple tests the thermostat will no longer let the A/C stay on. It turns on and then turns off again after a second or two. He checked all the wiring and said that it is all connected properly. He suggested that I replace the thermostat with a better one from Honeywell or the like.

Gas, forced air heat and A/C. Lux 1500E thermostat. Green to G, White to W, Jumper between RH and RC, Red to RH, Yellow to Y, Common to C.