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If you are dealing with a heat pump not turning on, then don’t worry. You are in the right place and very shortly we shall be looking at why your heat pump won’t turn on and the steps you can take to troubleshoot this issue.
Some of the reasons your heat pump is not turning on include thermostat issues, tripped circuit breakers, dead capacitor or relay starter, reverse valve issues and a few more others we’ll look at shortly in this article.
Troubleshooting a Heat Pump Not Turning On
When your heat pump is not turning on and you want to fix it, there are steps that you can take to troubleshoot this issue before calling in HVAC professionals. These tips could save you time and possibly some bucks. Let’s dive into these tips:
1. Thermostat Issues
Obviously the first thing you want to do when you are dealing with a heat pump that won’t turn on is check your thermostat. This is the easiest to check and fix. Make sure you look out for the following when you are troubleshooting your thermostat:
- Power connected to your thermostat. If your thermostat uses power by your home’s electricity supply, check if your thermostat is well connected and there are no loose wires. You also need to check if the C-wire is connected to the terminal. The C-wire handles supplying power to your thermostat and if its loosely connected, it could give your thermostat trouble running.
- If you are using a thermostat that relies on power from batteries, ensure that the batteries are not faulty or dying. Faulty batteries will prevent your thermostat from turning on your heat pump. On top of that, dying thermostat batteries will cause your heat pump system not to respond to cooling and heating changes
2. Tripped Circuit Breakers
After having checked with your thermostat and everything with it seems to be all good. The next thing you need to do is check for any tripped circuit breakers for both the indoor unit and the outdoor unit of your heat pump. It is also worth noting that:
- Heat pumps can at times trip the circuit breakers. If you notice any tripped switches, flip them back on.
- You need to check the power switches for all components of your heat pump. The power switch for the indoor unit is usually found near the air handler while the switch for the outdoor unit can be found close to where the refrigerant lines run inside. Make sure they are all on. Tripped circuit breakers could be the reason your heater is not working
3. Dead Capacitor Could Be the Reason Your Heat Pump Won’t Turn on
The capacitor gives the motors the electric charge they need to start working. If the capacitor is not working or is dead, it won’t do its job and your heat pump won’t turn on. You can tell when you have a bad capacitor if:
- You hear a clicking sound from your outdoor unit when your try turning on your heat pump. At this point, it is smart to call for HVAC repair services.
4. Reverse Valve Issues
The reverse valve switches the direction of the refrigerant so that your heat pump can work as a heater and as an air conditioner. Sometimes a reverse valve will become faulty and when this happens, it could be the reason for your heat not turning on.
A malfunctioning reverse valve can be replaced with a good one. However, for this job you will need to call in professionals.
Why is my Heat pump compressor not turning on?
When you are faced with a heat pump compressor not turning on problem, this could be caused by a few things that include:
Power is not getting through to your outdoor unit.
To resolve this issue, you need to check the heat pump power switch usually found on the exterior wall near the heat pump’s lines leading into your house. If you rule out the power switch problem, head over to check for any tripped circuits.
Malfunctioning Relay Starter and Capacitor
A problematic relay starter or a dead capacitor could prevent your heat pump compressor from turning on. The capacitor is there to start your compressor, and the relay starter transmits power from the capacitor. I won’t go into all details but if you are hearing a humming sound after you turn on your HVAC system, the compressor might just be trying to access capacitor that is not working. The relay starter and capacitor can be replaced easily. However, you can call HVAC professionals to come and take a look.
Typically, a certified HVAC professional should be able pinpoint the source of the problem. If the capacitor and the relay starter are in good working condition, your compressor could be one with the problem. It could be actually dead.
In this case, a replacement of the compressor will be needed to bring back your HVAC system on its feet. As a rule of thumb, if the cost of replacement is higher than half the cost buying a new HVAC system, its best to get a new one.
Why is My heat pump emergency heat not working?
Emergency heat is there to supplement your heat pump’s heating when temperatures drop to a level where your heat pump could not heat efficiently. Typically, your emergency heat can be a furnace or a boiler. Not all heating systems have emergency heat settings. I am assuming yours has.
If your heat pump emergency heat comes from an electric furnace, you can start troubleshooting by first checking the following:
- Furnace power switch: Your furnace power switch might have accidently been turned off. You need to check it its in the ‘on’ position.
- If your furnace power switch is on and emergency heat is not working, you need to check with your circuit breakers. If any breakers have tripped, flip them back on.
- Your emergency heat setting may not be working. In this case, you’ll need to contact an HVAC guy to come and examine your thermostat.
I hope this guide has been helpful for you in one way or another. After having tried these tips and you have the heat pump not turning on problem, perhaps try getting help from professional service. To prevent any other unforeseen issues with your heat pump, it is good practice to have maintenance tune up twice a year.
HVAC tech with over 30 years of experience. Retired and doing repair work on the side around Madison County, AL.