My mother has an intertherm furnace in her mobile home. I am not sure of the model number but anywhere between 2 and 5 weeks the furnace has to be relit. It lights easily but will not continue to stay lit. We have replaced the termal couple 3 times in one season, had the gas valve replaced and the technicians that seem to be in and out tell me they have no Idea why. They say it is clean and every part that can be replaced has been replaced. It is costing a fortune and a lot of time. Is there anyone out there that can help me with this. Tired of not having a furnace I can depend on.