Ran into a Lennox that has me pulling my hair out. 3 Ton package heat
pump. It is approx 10 years old with no more than routine maintenance
needed since installation ,until a couple of weeks ago. Condensing motor
keeps going out on thermal overload. First call, it seemed that it was a
bad defrost board. Replaced that, unit did o.k. for 3 days then, out again.
Voltage is 235VAC. The compressor and indoor blower continue to run after
cond. motor quits. To date I have replaced the board, the time delay,
the 1/3 Hp 1075 (original) motor and cap. and have thoroughly cleaned the
coils (twice). I baby sat it for over 3 hours. Unit will come on run between
20 minutes and almost an hour but when outdoor temp gets above 90 degrees
F. Motor will (Click) and opens on thermal again. This unit belongs to a friend
therefore no money has changed hands at my suggestion until it works.
According to Lennox, the original motor was not a high temperature motor so
what gives with this. After 15 years in the business, I have never run into
this problem in the past. Any suggestions would be greatly appreciated.