New Thermostat - No Heat???

Old 10-22-07, 09:28 AM
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Exclamation New Thermostat - No Heat???

Hello maybe you guys/gals can save me a service call. I have a Rheem Seer 10 Criterion II Heat Pump with gas assist. I replaced the old mercury thermostat with a Honeywell rth3100c. Everything was peachy this summer with the AC. Now its cooling off and the Heat Pump isnt doing its job(my fault im sure). Heres the run down:
Thermo says "Heat On" and the inside fan is running but the outside unit is not until you set it 2 or 3 degrees over inside temp. At that setting you get "Aux Heat On" and the gas assist kicks on and the outside unit still does not run. Heats like a SOB with the gas running but notta without it. I am hoping i have it wired wrong so here is how i have my Thermostat wired.
Tan/pink? - C
Blue - B
Red -R
Green -G
Yellow -Y
White -E
And a jumper from E to Aux

I have two slots open which are O (orange im guessing) and L(no idea) but no other wires.

Any help would be GREATLY appreciated!!

PS i manually turned on the outside unit while the heat pump was trying to heat without gas and it worked fine.

Old 10-22-07, 12:48 PM
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At a quick glance, I would say your thermostat is not setup or programmed for heat pump operation. If it were, it would send the 24 volt power to the yellow wire in both heat and cool modes. The yellow wire goes to the heat pump condenser (outside unit). Since the outside unit turned on in a/c mode we know the problem is likely at the stat. A meter or 24 volt test light would be helpful too.

Check the manual and make sure it is set up correctly.
Old 10-23-07, 12:11 PM
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That L there is for the malfunction light in the tstat. Like said should turn on with R - Y and B for Rheem heat. O is heat on the 4 way vale in other units . With that jumper from E to AUX. I think that 2 o drop there is what turned the heat on for you on AUX. Like Jim said check the paper on the tstat see if set for heatpump
Old 10-23-07, 01:09 PM
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Here are what the terminals are for if your interested and need to check your wiring.

{Terminal name}, {color}, {function}
(R), Red, hot side of transformer.
(C) Common side of transformer (See B)
(Y), Yellow, Compressor activity (cooling or cooling and heating on a heat pump).
(W), (W1), (W2) White, "Heat" (gas burner, oil burner , electric heat, (auxiliary heat on a heat pump including defrost output from the outdoor unit to activate electric heat and turn on the AUX. heat lamp). Note: some thermostats require a jumper from "W" to "Y" for heat pump operation.
(G), Green, furnace blower fan. (needed for air conditioning, heat pumps and some electric furnaces). NOTE: on most thermostats the "G" and "Y" are connected together at all times when the fan switch is in the "Auto" mode!
(O), Orange , Energize to cool (used for reversing valve on heat pumps)
(B), Blue or Orange, Energize to heat (used on some systems, Rheem/Ruud is notorious for this).
(B) or (X), Blue, brown or Black, common side of transformer. Needed on some electronic thermostats or if you have indicator lamps. Do not confuse with (B) Reversing valve (energize to heat) above. York and Trane like to use (B) as common.
(E), blue, pink, gray or tan, emergency heat relay on a heat pump. Active all the time when selected, usually not used.
(T), Tan or Gray, outdoor anticipator reset.
Used on GE/Trane/American Standard and some Carrier Products.
(W2), Pink or other color, second stage of heat (may be same as (W) on heat pump or fossil fuel system).
(Y2), Blue or Pink, second compressor stage.
(L), Blue, brown, tan or gray service indicator lamp.
Numbers, see manufacture's diagrams but can be stages of electric heat especially on York/Borg Warner/Coleman-Evcon, Frasier Johnson/ Air-pro.
(X2), Second stage of Electric Heat on GE/Trane/American Standard. See link above. Also used as indicator lamp or misc. contacts on other systems.

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