I,ve had a tech to my house twice to service a balky dc induction motor on my 10 year old hi eff furnace. i,m very appreciative of the consideration for the potential replacement cost for that item; and the effort to boost the life expectancy of that grumpy motor. so far, so good. a little grumble during start up is tolerable. i,m the same way in the morning. I have been a happy amazing customer for well over ten years. good work!