Checked the Lennox unit heater for the warehouse for no heat. Found a inline fuse in the 120 volt supply curcuit to the unit with a loose connection at the fuse holder. Removed the fuse from the curcuit. Started the unit and verified operation. The fuse is not needed as the unit is protcted by the breaker panel. Lba installed the unit 12/14/17. The unit has not been serviced since the install. Warranty.