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jimpowell1
Nov 8, 2008, 09:33 AM
I recently replace my 5 wire thermostat with another one. Color coded my wires and everything. Now I have heat but no a/c, unless I switch the RC and RH ( blue and red )wires, then I have no heat but a/c. is there another problem? Nothing worked, so I replaced the thermostat, and now have 1/2 but not all? I am handy, but not an electrician. This is how it is hooked up.

RH - red wire
RC - blue wire
W - whire wire
Y - yellow wire
G - green wire

There is also a red/white wire coming from my unit ( a/c compressor? ) outside.

The red wire is hooked up to RC
The white wire is hooked to the Y

Very frustrated

hvac1000
Nov 8, 2008, 09:48 AM
Brand and exact model of old thermostat.
Brand and exact model of new thermostat
Brand and exact model of furnace or equipment.

Is this a heat pump system?

jimpowell1
Nov 8, 2008, 10:00 AM
Thermoststs are thr same honeywell RTH110B, furnace is carrier 58sta110-22100 a/c unit is carrier 38brc060360.

hvac1000
Nov 8, 2008, 11:08 AM
You did not answer my question of ((Is this a heat pump system? ))

Why did you replace the thermostat? What was the original problem?

jimpowell1
Nov 9, 2008, 07:32 AM
It is not a heat pump. I replaced the thermostat because the units would not come on at all. Then I learned I had to have something to start the compressor outside. But when I replaced it I still had to switch the wires to get the ac to come on. It is like the red wire has power but the blue one doesn't. What ever you hook to the red wire to works. I have thought about unhooking the blue wire and installing a jumper from RH to RC, but all 5 wires were used on the old tstat. I think I have another problem, but don't know what it is.

jimpowell1
Nov 9, 2008, 07:33 AM
This is the unit I have
http://www.docs.hvacpartners.com/idc/groups/public/documents/techlit/om58-123.pdf

hvac1000
Nov 9, 2008, 09:03 AM
Stop switching wires. That does not cure the problem at all.

Remove blue wire and tape off.

Jump RH and RC and put the red wire on RH or RC since it will not matter since they are jumped. You only have one low volt transformer as far as I can tell.

White to W
Green to G
Yellow to Y

And remember Leave blue Unattached and taped off for now.

This is the standard universal wiring setup for most systems and should work if the wiring at the furnace uses the same color code and letter combo. I have no idea where the blue connects in the furnace since those connections were not addressed.

If this setup does not work it is time for you to call for On SITE professional HVAC service.

With the limited information provided this is the best that I can do.


Below is a electronic copy of your thermostat wiring diagram and instructions.

http://customer.honeywell.com/techlit/pdf/69-0000s/69-1799.pdf

Make sure the jumper J2 is set to HG

Make sure to set your configuration menu item 4 on page 3 to default or where it is set from the factory just in case you changed it for now.

Make sure the batterys are installed as per the instructions and they are fresh or known good.

RichSchmidt
Jan 16, 2011, 12:47 PM
I own a Rheem a/c unit and the (attic ) heater is natural gas powered. Right now I have five wires coming out the wall to the thermostat and it presently hooked up to a White-Rogers thermostat but the wires are not all going to the correct terminals(Y to yellow, blue to B, etc.) the heater seem to go on before the heat chamber has heated up the air (winter time) and we get cold air for a few minutes before it gets hot.I would like to change over to a Honeywell-non programmable but how do I factor the five wires in?