They said the A coil was leaking & replaced A coil (with an N coil). Freon was completely gone. He was having trouble getting it to work, so said the thermostat was also bad. Replaced that too. Right after he left I was going back to work & the outside temp was cool, so I turned the thermostat off, but the unit would not turn off. I had to flip the breaker & turn the switch on blower off to get it to shut off.
They came back out. Put another thermostat on (the first one they put on had setting for heat pump which I DO NOT have). Next day outside temp got down to 42 at night so in morning (it was 63 in house) I turned heat on. Furnace kept cycling off after about 2 min. of flames. Called them back out. As info, I had never had trouble with the furnace until they changed evap. coil. They have been out twice since then & can’t seem to figure it out. Even the owner has been out & says it is an air flow problem. It will run with filter out & front cover off of the furnace. I told him heat has never been a problem before and the only thing that has changed is the evaporator coil. Could it be because the A coil was replaced with an N coil?
The owner discussed with a Carrier rep and they said to replace the high limit switch. When he was out here he also mentioned how hot the flu was. Wouldn’t replacing high limit switch only make it run hotter? I am very worried they don’t know what they are doing and don’t want to have a fire. The owner & his service guys have been good about continuing to come out. Even though the service guy has made several mistakes. After filling with freon he left valve caps off & when they came back out after I couldn’t get it to shut off, the owner tested pressure & it had already leaked 2 lbs. freon from previous day because caps were left off. Even with the warranty, it cost me $500 for the new evap. coil. They have not charged anything since. But it has not worked correctly since they replaced the coil. Any advise?