Jann's condo has a Bryant Furnace with Carrier central air conditioning.
I replaced her first thermostat, an old Honeywell that was corroding away with a Ritetemp (which I later discovered comes from Home Depot) programmable a co-worker gave her. When A/C season came she couldn't get cold air. She was about to call for service when I decided to crack open the thermostat. I see a sticker inside that says "FIRST push the reset button." The reset button is a pinhole that you need to put a paper clip in. I pushed it and suddenly we had A/C.
Life is good until a few weeks later we have no cooling again and we're boiling in the middle of the night. I groggily go over and push the reset button. It works again.
So we decide to replace the piece o' crap thermostat.
I got a Honeywell 5-2 which I put in this morning. I notice on the way that the Rh-Rc jumper wire in the old stat was loose even though I had tightened down all of the screws when we had trouble. *sigh* That could have been it.
I carefully note wire locations and installed the new one. It works fine and looks to be much easier to program for Jann.
But it doesn't seem to be getting cool. It's warm. The fan is running full tme. The air coming out doesn't seem to be cold and blowing much.
I double, triple, quadruple checked the wiring.
The temperature at the stat gets to 77 degrees and stays there.
I opened up the furnace and spent over an hour making sense of how the furnace side was wired and whether the thermostat side as I understood it made sense. It did. I even checked the wiring diagram inside the cover of the furnace which mostly showed the internal wiring, not the external.
I found a web site that explained how things should be wired. http://xtronics.com/reference/thermostat_wires.html It turned out that my understanding was exactly correct. The colors of the wires in the cable don't match but what they are and where they go does.
Finally, knowing that if I short Rc/Rh to G and Y; I should be calling for full cool. I do that. The A/C works the same as it did when the thermostat was connected.
I vaguely recall that we had the same problem the first time I replaced the stat and when the reset was needed. It seems like when the A/C is cooking the fan motor runs at a faster speed and the heavy cooled air noticibly pours out.
I noticed that the furnace has a multispeed fan. I can't imagine how it decides to change the fan speed. Would it make it faster for cooling vs. heating? It could know that based on the G wire which AFAIK isn't used for heating.
We finally gave up and I shut it down with the power switch. As I remember the last time, after we let it rest for several hours it came to life. Could it be that the compressor gets air in the lines due to the excessive power cycles while I'm messing around?
Anybody have any ideas?
We're about to call in the $$$ troops. Worse case they can charge the refrigerant (I hope).
I replaced her first thermostat, an old Honeywell that was corroding away with a Ritetemp (which I later discovered comes from Home Depot) programmable a co-worker gave her. When A/C season came she couldn't get cold air. She was about to call for service when I decided to crack open the thermostat. I see a sticker inside that says "FIRST push the reset button." The reset button is a pinhole that you need to put a paper clip in. I pushed it and suddenly we had A/C.
Life is good until a few weeks later we have no cooling again and we're boiling in the middle of the night. I groggily go over and push the reset button. It works again.
So we decide to replace the piece o' crap thermostat.
I got a Honeywell 5-2 which I put in this morning. I notice on the way that the Rh-Rc jumper wire in the old stat was loose even though I had tightened down all of the screws when we had trouble. *sigh* That could have been it.
I carefully note wire locations and installed the new one. It works fine and looks to be much easier to program for Jann.
But it doesn't seem to be getting cool. It's warm. The fan is running full tme. The air coming out doesn't seem to be cold and blowing much.
I double, triple, quadruple checked the wiring.
The temperature at the stat gets to 77 degrees and stays there.
I opened up the furnace and spent over an hour making sense of how the furnace side was wired and whether the thermostat side as I understood it made sense. It did. I even checked the wiring diagram inside the cover of the furnace which mostly showed the internal wiring, not the external.
I found a web site that explained how things should be wired. http://xtronics.com/reference/thermostat_wires.html It turned out that my understanding was exactly correct. The colors of the wires in the cable don't match but what they are and where they go does.
Finally, knowing that if I short Rc/Rh to G and Y; I should be calling for full cool. I do that. The A/C works the same as it did when the thermostat was connected.
I vaguely recall that we had the same problem the first time I replaced the stat and when the reset was needed. It seems like when the A/C is cooking the fan motor runs at a faster speed and the heavy cooled air noticibly pours out.
I noticed that the furnace has a multispeed fan. I can't imagine how it decides to change the fan speed. Would it make it faster for cooling vs. heating? It could know that based on the G wire which AFAIK isn't used for heating.
We finally gave up and I shut it down with the power switch. As I remember the last time, after we let it rest for several hours it came to life. Could it be that the compressor gets air in the lines due to the excessive power cycles while I'm messing around?
Anybody have any ideas?
We're about to call in the $$$ troops. Worse case they can charge the refrigerant (I hope).
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