This would be the last resort. The tech showed up smelled of BO went into my attic. Footprints all over the ceiling access to attic. Was in attic 15 minutes. Came down brought me estimate of $3310 said I had to replace the whole unit. Paid him his $25 got rid of him. He was new here from Chicago. My first red flag. The next day I had a reputable company come to inspect the heater. They took pictures of the damage this guy did. He cut wires pulled wire out of the unit cut and left electric fitting on attic floor. I am going to take the pictures to the state licensing division & the Consumer protection agency. The company that came inspected the unit & could not believe what this guy had done. It ended up being a circuit board. It cost me $600 to fix the damage. This company is a rip off pure & simple. I have been in the construction industry for 40 years & this is the worst situation I have seen. Blatant misrepresentation, arrogant & crooked! BEWARE