Heating, Air Conditioning, Fridge, HVAC/Ruud 3 ton heat pump


QUESTION: I have a Ruud 15 seer heat pump using the new 410 gas installed back in the spring. It worked fine through the summer, but not so good so far this winter. Right now I am having trouble with the Aux heat strips not coming on when the unit gets behind. The air coming out of the closest vent is only about 80 degrees steady with the pump only running. Is there simplified wiring diagram for the unit / stat that I can use to double check my wiring and should the air temp from the vent be warmer than 80 degrees?

Sounds like the electric heat strips are not coming on?
Check the electric  circuit breakers, make sure they are on.
Sounds like everything is working except the strip heaters are not kicking in, could be everything from the thermostat to the strip heaters?  There should be wiring diagrams stuck on the inside unit some place.
The air temperature coming out of the supply  depends on what temp it is going in? 80 is about right for no heat strips working.

---------- FOLLOW-UP ----------

QUESTION: The strips do work when I swithch the stat to emergency heat, so they should have power. The indicator on the stat says it is telling them to turn on but the air temp coming out of the vents never changes. I have looked at the wiring diagram on the air handler and believe that it is hooled up correct, but it is a little confusing, so i could have it wrong. I am going to double check and I will get back to you.

Thanks You for the response.

It sounds like the trouble is in the thermostat, check the thermostat wiring from the thermostat to the air handler for loose or broken connection.
If the strips come on when you switch to emergency heat its doing manually what the stat should do automatically.
When emergency heat is on if the strips come on I'm sure the air temperature is above 80.

---------- FOLLOW-UP ----------

QUESTION: You are correct, when switched to emergency heat, the air temp at the vent is 87-90. I rechecked the wiring and here is what I have currently:

Air Hand.        -      Tstat      -   Condensing unit
(y1)Yellow       -     (Y)Yellow   -   (y)Yellow
(W2)WH/BL stripe -     (AUX)White  -   (D)Purple
(W1)WH/BK stripe -     Not used    -   not used
(G)Green         -     (G) Green   -   not used
(C)Brown         -     (C)notused  -   (C)Brown
(R) Red          -     (R)Red      -   (R)Red
         -     (B)Blue     -   (B)Blue
         -     (E)not used
         -     (O)not used
In this configuration the Emergency heat will not work when switched on at Tstat. And the Aux heat will still not come on when the Tstat calls for it. I can get the emergency heat to work if I move the white wire to (E) on the stat and switch it on manually.
The diagram on the air handler says to tie the (W1) and (W2) wires from the AIR Hand. together with the white wire for a 13KW Faster heat rise. I have not tried that yet.
Also I only have 1 white wire coming to the Tstat. I can either hook it to the (AUX) or the (E), Would a jumper wire between the two at the Tstat make both functions work?
The (B) Blue wire goes directly from the Tstat to the condensing unit to control the reversing valve

What do you suggest?

Again thank you for your help

Evidently everything is working as it should except the thermostat isn't doing it's job.
The red wire that ie connected to the R post on the thermostat is the hot power wire going into the thermostat, when you switch the thermostat so it calls for heat the R switches to the W, W is for heat.
You can take the R and W loose from the thermostat and twist them togeather, the heat should come on.

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Jim Barnhart


Fifty + years conditioning the air.


Answer questions about , residential and commercial. Answer questions about sheet metal fabrication. Fifty years plus experience. No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances, I don't specialize in one particular area of the HVAC area, I'm more of a General Practitioner, Limited in refrigeration/

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