Performed diagnostic on heat pump, upon arrival customer stated tenant stated heat stopped working, checked both tststs, cycled to heat mode , nothing came on, went to attic to inspect unit, found no lights on zone board, checked voltage no voltage to unit, getting 120v to each leg but not 240, upon checking disconnect found melted, recommended replacing disconnect to get voltage to unit, customer approved, replaced failed disconnect with new disconnect, tightened all screws , after replacing disconnect unit started up, checked heat strips amp draw, checked ok, checked pressure, temp split, everything working properly at time, still recommend TE flood protection wet switch as well as uv protection, sent estimates over to homeowner