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Heat Pump Thermostat Wiring Chart Diagram - HVAC - The following graphics are meant as a guide only. Always follow the manufacturer’s instructions for both the thermostat and the HVAC system. Additional articles on this site concerning thermostats and wiring can help you solve your problem or correctly wire a new thermostat.
Heat Pump Thermostat Wiring Chart Diagram
Some HVAC manufacturers use other colors for additional control points and it is why we advise you to read the manufacturer’s instructions. These charts and diagrams only represent the basic system. It is possible your system is equipped with additional HVAC components such as a humidifier or electronic air cleaner. Depending on the manufacturer and the designer of the components will depend on how the additional components are wired or integrated into your system or thermostat.
Heat Pump Thermostat Wiring Chart Diagram
The Basic heat pump wiring for a heat pump thermostat is illustrated here. It corresponds to the chart below to explain the thermostat terminal functions. Before uninstalling the old thermostat take a picture of the wiring with your cell phone before removing the wires. This way you have a reference. At the minimum draw a picture of it referencing the wires, wire color, and what terminal the wire is attached to what terminal. The photo and the drawing reference can be used later to make sure you wire the new thermostat properly.
Heat Pump Thermostat Wiring Chart Diagram
Single-Stage Heat Pump Wiring Diagram
Heat Pump Thermostat Wiring Chart
That is for use for heat pumps. You should 100% make sure that you have a heat pump system and not an air conditioner with electric heating strips as it is a common mistake for people to misidentify their HVAC systems. Make sure you do not make these same mistakes others make. Air conditioners are different because the reversing valve and defrost controls are unnecessary.
Heat Pump Thermostat Wiring Chart Diagram
Additionally, remember the RC/RH jumper is only for a heat pump system that has one transformer. Does your system have two transformers? It is rare but still possible. If you have a conventional split system air conditioner or heat pump and there is a jumper from RC to RH, then you have a single transformer and do not have to worry about two transformers in your system.
If you are having problems getting it to work it is crucial to make sure you have the same connections from the air handler to the thermostat to the condensing unit. Additionally, use our other resources here (other articles) for thermostat troubleshooting.
Heat Pump Thermostat Wiring Tips
- The above chart will help if you have a question of what color wire goes where? Wiring a thermostat has been designed to be easy. The colors such as Red are for hot and goes to the R terminal. Same with the other colors and terminals. However, depending on who wired the thermostat last, they may not have followed the wiring color code. Therefore, before removing any of the old wires, take a picture of the wires and where they are terminated on the sub-base of the old thermostat. Use your cell phone to take the photo for later reference.
- Always make sure you turn the power off before doing any wiring. Forgetting to do this may cause you to blow the transformer or trip a low-voltage breaker. Or blow a low-voltage fuse.
- You can find a comprehensive list for colors, what they, and where they go here –Â heat pump thermostat wiring colors
- Your heat may be different than the one described here. The heat pump wiring diagram above covers approximately 90% of the heat pump thermostats.
Heat Pump Thermostat Wiring Chart Diagram
See our other helpful HVAC calculators placed throughout the site:
i had my air handler replaced recently for my zoned a/c, heat pump system and i have a tstat upstairs and one down stairs. My problem is now when i turn my cooling system on the outside compressor starts to run then kick off and then back on. it does this until i completely turn the system off. can any one give me a clue as to what the hell is going on please.
Sounds like something was wired incorrectly or something recently went wrong. I would call the company that installed the air handler to rechecked everything to ensure it was wired properly. They should give you a one year warranty on all work. You should only have to p[ay if they find something outside of what they worked on is bad.
Mine is a two stage now what, it runs but blows cool air in heat mode
Cool is relative. Take the temperature at the return (where the filter is) and then take the temperature at one of the supply vents. There should be a marked increase in temperature from where it goes in to where it comes out. If there is little or no differential then you need to call a pro and have them check it out. You likely have a problem in that situation.
We’ve got an old 1992 Mobile Home (Serial #: CLA031915TN). The Insider Heat Pump in the mobile home is about to go out. The Model # on it is: CDHP35A150B; the Serial # is: 92020120. Address Box A, Olive Hill Kentucky 41164. Is it comparable to a Honeywell RTH3100C Heat Pump.
Paid a friend to replace my 2 air handler and heat pumps. These were the same units, one upstairs and one downstairs. I replaced them with identical new units from Rheem. They installed in the early spring and the ac worked great. Now that I have switched to heat the fan for the air handler never shuts off. It blows 24/7. The light indicating heat turns off once it reaches temp but the fan still blows and never shuts off….when the temp starts to drop again the light turns on and heats up the house again and light turns off….but fan still continues to blow. I noticed from the installation instructions my heat pump has 5 wires coming off of it to connect to air handler and thermostat but they used the existing wiring which only has 4 wires. So I’m assuming that’s where the problem is. The fan shuts off normally when using the ac in the summer.
You could be right about your assumption with the way it is wired. Run new thermostat wire and wire it the way it is supposed to be wired according to the Rheem diagram. You should only have to run wire from the thermostat to the air handler to resolve the problem. There are connections from the thermostat to the heat pump condenser so make sure you take that into account. For heat pumps I run 18-8 thermostat wire which is available here. It would not hurt to trace all the wires from the air handler to the heat pump to make sure that is also wired properly.
Did that work because i have the same problem with my rheem heat pump system.
I have all of my 5 thermostat wires hooked up in the right spot and my indoor fan continues to run in the heat mode. i have not replaced my T-stat wire yet or my T-Stat it was a brand new T-stat that came with the unit.
check to make sure the bare part of the green wire is not touching the bare part of the red wire. If so fix that, if not then replace the wire or call a pro to check it out. It could be a bad relay.
Thank you for these photos and info. Solved my heating issue because of you. “Repairman” disconnected my O/B wire when they replaced my air handler in the summer. Seems intentional but at this point, I don’t care. I have heat!
Glad we could help!!!
hi i have oil heat with a heat pump .I have installed a outside boiler and i am having to put another thermostat for the boiler .I have a new honeywell thermostat what two wires do i need to use yellow green red or what
Stand alone boiler the colors would be red and white but if you are trying to integrate all three appliances together that would be something a professional technician would have to look at as it would require either special wiring or a special thermostat that will stage up the heat pump, the oil furnace, and the boiler. There are several factors to be considered such as what is the desired primary heat source that you want and what is the most economical way to control everything among a few other factors. The answer is not cut and dry but it can be a complex set up for what you want to do.
Hi, nice job but I have seven (7) wires on the old one. Now what? Thank you.
Sorry but it is not enough information for me to give you a good answer.
well the good thing is that you have enough wires its plain and simple!!!!! just follow the schematic that was sent with your new thermostat but first verify that its a heat pump stat.that would be a start next some knowledge is required to to identify the way the old versus new stat. normally its a given yellow or blue for cooling,orange for o/b terminal g for green fan w/b for heat and r for red brown common
It is all here…………….https://highperformancehvac.com/thermostat-wiring-colors-code/
Great,that would help me out to wiring my heat pumps . but a have a question,how can I wiring my condenser if I got reversing valve out side and heating kit in my air closet unit?
Please see the following article here at High Performance HVAC – Converting and Air Conditioner to a Heat Pump
I cant seem to get a whole diagram anywhere from heatpump to airhandler/furnace to thermostat. If u can send a email i would appreciate it 🙂
I like the posting of the chart and the control panel connections. It helped me eliminate some things. My problem is still undetermined. Thanks for this information.