I have a 7 year old 3 ton Trane XR12 heat pump unit (2-stage heat, 1 cool)
servicing a 1500 sq ft single story house in North Texas. The outside
compressor is located in a western alley where it gets direct sun about
2:00 pm for a couple hours but is otherwise shaded by my/my neighbors
I like my AC cold, and have run this unit at 70 F for the past 7 years
without a hitch. The one air filter is changed monthly, anf the outside
coils are clean. Sight glass shows everything clear. The unit has performed
flawlessly, like a champ.
Recently, though, corresponding with some record high temperatures
beginning about the time the sun hits the outside unit/and/or the outside
temp hits 101-102 the unit stops produding cold air. Up until that point,
works perfectly, hits set point 70 with no problem. Just updated thermostat
to Honeywell 7-day, same behavior, that is, later in the evening, about
8:pm or so, when the outside temp drops down below 100, the cold air starts
up again and the house cools down as set on the thermostat. Ice cold, so
freon seems good. Rinse and repeat with each 102-3+ F day so far.
Is the unit, which outside of these extremes seems to work flawlessly/no
differently than last 7 years, protecting itself somehow with some type of
automatic limiting switch? Or is this indicative of some breakdown that
would require technician service?
Thanks for any insights. In the meantime, I'm warm now, I'll be cool
tonight and tomorrow morning, and mid afternoon forward tomorrow I'll be
warm again, unless something changes.