Brand new heat pump just installed all wiring is correct high voltage and low voltage but while its in cooling mode the back up heat is running. Why is the back up heat coil coming on while the heat pump is in cooling mode?
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Re: Ruud achiever heat pump
If back-up heat comes on when a/c is turned on and then the back up heat turns off shortly after the a/c turns off, then the low voltage wiring is NOT correct. Your "R" terminal is basically your "hot" and your "C" terminal is basically your "neutral" to simplify explanation. The Furnace supplies the "R" power to the thermostat and then depending on what wire the thermostat sends the power back on determines what the system does. The thermostat terminals are as follows "G" is fan, "W" or "aux" is elect heat, "Y" tells the outdoor unit to run, "O" or "B" tells the outdoor unit whether it is heating or cooling, and "E" is emergency heat. "G" should connect from the t-stat directly to the furnace and go no further. "W" or "aux" AND "E" should both connect to your "W" or "W1" terminal in the furnace, there should also be a "W" connection to the heat pump ( this allows the H/P to turn on the elect heat when the unit defrosts) "Y" and "O" or "B" may or may not connect to a terminal in the furnace, usually they just pass through the furnace from the t-stat to the H/P and get wire nutted in the furnace. Now, here is the key. As I mentioned previously "O" or "B", a system will only use one or the other. The entire industry (except for Rheem and Ruud) uses the "O" terminial which has 24v on it when you are cooling and no power when you are heating. Rheem and Ruud use the "B" terminal which is just backwards, 24v in heating and no power in cooling. this could also be your problem if the t-stat thinks it is telling the H/P to cool but the H/P is actuall interpreting the signal to heat. Check your amp draw on the furnace, if you have anything drawing 15 amps+ then it is most likely the actual elect heat running, if not then check the "B" terminal. Most universal t-stats come set from the factory to use the "O" terminal which is more common. Usually this can be changed in the installer setup menu on the stat or sometimes the stat will have separate "O" and "B" terminals
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I think that you have the right idea. The wiring is probably wrong. If you can trace the low voltage wires to the air handler. make sure that the Y1 wire on the t-stat is going to Y1 on the hair handler and then to the condenser. The Y2 wire should be going to Y2 on the air handler and probably does not continue out to the condenser. The Y2 should be going to the contacor that brings on your backup heat. It seems like Y1 and Y2 are reversed somewhere.
Definately get this checked out. Some thing has shorted just enough to let voltage "Feed back" and keep the fan running. Could be capacitor, wires rubbed through each other, etc. A reset is a safety that is used when there is an overcurrent or over pressure situation. No reset set for this situation.
There is always an outside chance that if you touch the unit while standing on wet ground, you may get shocked. I firmly believe that something is allowing power to the fan in a feedback condition so don't let this go as it may cause damage to other parts.
Good Luck and let me know how you make out on this.
Do you have gas or electric heat. If you have gas then you do not have a heat pump. You should in most cases have a red,yellow, white, and green wires coming to the thermostat. R should go to rc/rh G should go to green Y should go to Y and w should go to W. Also the switches on back should be switched to non heat pump and gas rather than electric. Hope this helps.
Did you just install this heat pump? If so it sounds like you replace a regular a/c with a heat pump, which will require more wires for the reversing valve. First check to make sure you have 24v going to the condenser. Make sure you have a heat pump t-stat. You should have a orange t-stat wire for your reversing valve. At the t-stat you will have terminals R, Y, G, O, X or C or B, W1, and W2. R is half of your 24v circuit and is a red wire, Y is for cooling mode, G is the Fan green wire, O is for the reversing valve, orange wire, X or C or B is the other half of control circuit blue wire, W1 and W2 is the heat strips in the furnace tan and black wires. These are standard color code but remember electricity does not know colors and an installer may have used different colors. If all of this is correct possibly bad contactor.
Start with the simplest first it,s not fun but it's necessary EVERY TIME. Clean your evaporator and condenser coil, change your air filter. Getting to the evap. coil is often a real headache and a result doesn't get done often. When its clogged as you probably know the refrigerant can't absorb heat at the coil so it tries to absorb heat on the way to the compressor freezing the hot gas line the safety circuits that protect the heat pump compressor from getting liquid refrigerant back to the compressor almost immediately will take the compressor of line (looking somewhat like a defrost cycle). I hope this helps it's a tough repair GL!