I have a 2 yr old Trane furnace. Last night we noticed it was blowing out cold air. I checked the light on the furnace and read the code box that said "open limit device". I called the company we purchased it from and was told the limit switch needs to be replaced. The parts are covered but the service call & labor aren't. Don't have the extra money right now to get it fixed. Any suggestions? Can I buy this limit switch from a parts store and replace it myself or is it too complex? My buddy said I might not be able to buy the part since I'm not HVAC certified. Is this true?

Thanks!

Very simple to install,, many have a reset button,, check it out before you buy one, on the door should be a parts discription and diagram to tell you where to find,, the reset button is right in between where the 2 wires are connected