Honeywell RTH8500D Tstat

I hope that someone out there can help me. I have just purchased a new house and I wanted to make sure and swap out the cheap thermostats that came with it. I have installed the thermostat in both my upstairs unit and my downstairs unit. My downstairs works like a charm, but my upstairs is having serious issues. The major issue, is that the freon pipe freezes up all the way to the outside unit and even when I set it to 76 or 78. I am in atlanta and it has been in the mid-upper 80's which the A/C unit should handle.... It seems once that pipe freezes the air get less cool, but it should freeze so much. It freezes every day regardless of what temp it is set to. The 2nd issue and this is what leads me to belive there is something wrong, is that whether it is on heat or cool, I only get cool air? Any suggestions? I don't know a great deal about hvac, but I believe it is a single stage heat pump with no aux. I have my 170 set to 2 and my 190 set to 0. If I set 190 to 1 then I just get room temperature air. Please help me. I have spent so many hours trying to get this thing right. The most troubling issue is that the unit downstairs has the same settings, but no problems. Thanks in advance...
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On 11 Aug 2005 23:03:17 -0700, snipped-for-privacy@gmail.com wrote:

You need to call for service. a Freezing coil can be one of many things such as, low air flow, Low refrigerant charge, etc.. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ spam protection measure, Please remove the 33 to send e-mail
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The control wiring is wrong. Make a note of the letter designations and cable colours in the outside Unit and note the letter designations they are connected to in the thermostat. Compare these with the control wiring of the downstairs unit and thermostat.

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Yeahm I know, but it is too late for that... What do I do?
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The control wiring termination at the new thermostat is wrong. When you took off the old thermostat you connected the terminals of the outside unit to the wrong terminals at the thermostat. Look at the cable terminations on the downstairs outside unit and note the cable colours. Then note the cable terminarions in the thermostat. This tells you for example that w on the outside unit should be connected to a certain terminal at the thermostat. Then look at the cable terminations of the upstairs outside unit and note the cable colours. Then note the cable terminations in the thermostat. Compare these connections with the downstairs unit and swop the appropriate wires so the upstairs unit is correctly terminated at the thermostat.

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Thanks so much.. I noticed that the upstairs uses a blue wire and the downstairs uses brown wire... Thanks to all and I will try it first thing tomorrow morning...
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I checked the differences at the air changer and I found that downstair the yellow wires are connected to each other, but in the attic the yellow wires are each connected to a black wire that goes into what looks like a drain inside the unit.. Should I connect yellow to yellow and see if that fixes the issue? Any addtional help would be greatly appreciated... I can post pictures of wiring if anyone thinks it will help...
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The exact make and model of the Air conditioning unit would do it.

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