A friend of the family (widower) call me to say her pellet stove (CB1200) was not working. I checked fuses & both snap disc,s on the left side, both were good. I saw from the paper work that the unit was in warranty until March 2013 & suggested that she call the dealer. I let the tech in & stayed with him while he was in the house. First thing he says, "He changed the stat & the unit might not be under warranty." I said that the stat is merely a switch & where in the warranty does it say about a certain stat. He could not figure out what was causing the problem. He stated that he would have to get a hold of Quadra-Fire Tech to find out they would say. The next day he came back & stated that he would have to take the unit to the shop. The following week he brought the unit back & said that he blew out the unit with a compressed air hose, changed the resetable snap disc ( yellow wires). I told him that I checked that snap with a multi meter (contunity) & it was good. The unit has been working for the last three days & the bill $192.00. They still do not know what was cause that the unit not working. My point is, they complained about the stat, that ash was blocking the exhaust, they were fishing to void the warranty. Told her to request a written report on the cause of failure.