Hi - I'm seeing some odd behavior with my Evolution thermostat. Because my relationship with my contractor is a bit estranged (see my other
posts), I wanted to see if anyone here could help my understand my problems better before I go out and try to get help. I have an Evolution A/C system in my attic (no heat) with it's own stat in the living area. No zones. I'm noticing two things that concern me:
1) I keep the default fan setting at Medium. This improves air-filtering (we have allergies) and provides a little white-noise at night. However, what I've observed is this: If I OVERRIDE the pre-programmed temp and the stat calls for cooling, it forgets the preset fan setting and operates as if the fan is set to AUTO. Cancelling the override does notchange this behavior. Only if I turn the stat OFF and turn it back on, does it then again respect the user-selected FAN setting. Honestly, this sounds like a firmware bug, and I'm not sure replacing the stat (or a circuit board on the air-handler) would make any difference, so I'm not sure what to do.
2) There is an external thermometer on the compressor and an external temperature display on the thermostat. This reading is usually right-on.
However, sometimes, usually in the morning, it reads as much as 11 DegF too high. I even witnessed the stat display change by 3 degrees at once this morning. (unfortunately, the outdoor unit is in the West corner of the house, so I can't attibute this to direct sunlight). I'm not sure how important it is for the stat to always have the exactly correct temperature. I'm also not sure if it's the sensor or the stat.
I know that one response to this post is "go get a d--n professional to look at it", but I'm curious if anyone here is familiar enough with the system to suggest what could be wrong, or what I could do to debug it further. If #1 is really s firmware bug I may be out of luck, and I don't really have the luxury of dragging a contractor into this unless I'm going to get some benefit from it.