In 1990, when I started as a service technician, I had the privilege of working on literally thousands of these Lennox Gas Furnaces. If you are a technician this is a must see video on where these Lennox curved heat exchangers fail.
Remember to always check the following when and if you find a failed heat exchanger on a Lennox furnace or any other furnace with a cracked heat exchanger.
- Static Duct Pressure
- Filter size
- Evaporator coil
- Number of supplies and returns
- Gas Pressure
- Delta T
- Perform a combustion analysis
- Check for gas leaks