Product review (5 stars): Works on a Trane
My 9 year old unit died and the A/C company wanted $229 to install another one, which was a newer, more digital device, but it just did not fit the hole on the stack without a crummy patch job, so I told them NO! For $35 bucks I put my own replacement in and it was just 4 wires. Don't pay for 10 minutes of install time when you can do it yourself.