I have a Trane 2 stage XL80 downdraft furnace. I had a new 2 stage motor and and fan installed by a certified Trane Dealer and after the installation the unit vibrates the whole house. The unit is only 8 yrs old and was installed in a new constructed house in 1997. The installer stated that its was the best he could do, that response is not acceptable me, because the unit wasn't doing it when it was new. I want to tell this installer to come and take the so-called new motor and fan out and give me my money and I'll start all over trying to located a better installer. Any help with this dilemma would be appreciated....