On 12/7/2014, we had a system lockout. We were told it was a leak, later told the leak occurred as a result of a faulty outside fitting and possibly the wrong braze had been used in the installation. It was repaired, we were charged $697 for a freon recharge but not charged for labor or parts. On January 2, 2015, we had another system lockout. This was repaired 1/20; they replaced both inside and outside TVX (valves). We were told the outside value probably got sticky when the freon was dumped and the service manager likes to replace both valves at the same time. By the time the service manager got home on 1/20, we had another lockout, due to pressure. They came back the next day and the service manager installed a return and (?) another vent in the basement duct work to solve the pressure issue. Sorry I am not able to explain this better.
It seemed to be working fine but I noticed the last several days that the control panel reading of the outside temp was showing about 15-20 degrees lower than it actually was outside. This was especially apparent today when it read 20 degrees - it was really 40 degrees and we were running on resistance heat! Now I am especially sensitive to running on resistance heat since we received the biggest electric bill we ever had with all the service issues over the past month- over $1,000 - (and were keeping it cool knowing we were on resistance). At 40 degrees outside, we never used resistance heat as I recall.
I am wondering this: If the system is reading the temp outside as 15-20 degrees lower than it actually is, would that cause the resistance heat to kick on? We don't know enough about HVAC to know the answer to that very basic question. It feels colder with resistance heat - plus I hate wasting the money. Maybe this is a simple control panel programming issue?
I really thought we had a few years of no expense except two annual cleanings. So disappointing.