Lennox furnace repair / maintenance, condensation trap cracked ( sealed with caulking ) inducer motor starting to vibrant and make a small amount of noise , no other noise heard while testing , furnace was over heating I have change heating tabs from yellow to black to allow more air flow , ac evaporator coil is clean, furnace is still cycling off on high temp , blower motor amps are good , wheel is fairly clean , motor could be failing , customer only have two returns up stairs , I have recommended to possibly add one more return down stairs