I was told by a tech that my five year old Trane XL 90 needed a heat exchanger. The part is under warranty but the labour would be $1000.00 (does that sound right?). I have looked at my contract and it states that the warranty covers both parts and labour. If the warranty covers parts I figure it should also cover labour, correct??
Also does it make sense that a 5 yr old furnace should be needing a heat exchanger? This is the first time that I have had to change a heat exchanger and I have had furnaces well over 20 years old?
I would call the a/c contractor and discuss the warranty with them. If the tech quoted this, he might not have known about your warranty. If you are questioning the diagnosis, ask for a senior tech to come out. Have him check the static pressure of the duct system as well as the heat exchanger.