Why Is My Heat Pump Not Heating?

A heat pump not heating usually means you have a dirty air filter, low refrigerant levels, or a blocked outdoor unit.

● You should replace the air filter for your heat pump at least once every few months.

● The solution for most heat pump problems in Florida is to schedule preventative maintenance at least once a year.

Cold weather isn’t fun, especially if the cool air makes your body hurt or prevents you from feeling comfortable in your own home. If you constantly have to turn the thermostat up higher, you probably wonder, “Why is my heat not working?” This heat pump troubleshooting guide can help you discover the best fixes for a heat pump not heating.

Is Your Heat Pump Turned On?

Believe it or not, one of the most common causes of a heat pump not heating is that’s it’s turned off. If this is the problem, your heat pump won’t be running at all. Fixing this is so easy that it’s worth taking a few minutes to check it out.

One reason the heat pump may turn off is that a circuit breaker trips. Check your breaker box to see if any of the electrical switches are tripped. If so, turn them on again. Problem solved!

Another reason for a heat pump not blowing air is a faulty thermostat. Older thermostats sometimes read the wrong indoor temperature. When a defective thermostat thinks the inside temperature is already 75 degrees, it won’t tell the heat pump to turn on.

Is the Thermostat Set to Heat Mode?

The next-most-common problem is that the heat pump and thermostat actually work just fine, but someone at home accidentally flipped the switch from “heat” to “cool” or “fan.” If the thermostat is set to fan mode, the HVAC system will run normally, but instead of hot air, you’ll feel cool air blowing out of the vents.

Follow these three steps to fix the issue:

1. Change the thermostat setting to heat mode.
2. Turn the fan setting to auto mode.
3. Set the thermostat to the house temperature you want.

Accidents can happen, especially for families with little kids (or when grandkids come to visit). Checking the thermostat settings can help you catch any errors and get your home’s temperature back to normal again.

Is the Thermostat in Direct Sunlight?

Does your heat pump only misbehave during certain times of the day? In that case, it’s possible the sun is messing with your thermostat. If the thermostat is in direct sunlight, the sensor can heat up and cause false temperature readings. It can be a chilly 60 degrees inside, but your thermostat is so warm it thinks the home is already at 70–75 degrees.

The best solution is to move the thermostat to a spot that is protected from direct sunlight. Our technicians can help with this, and you can even take advantage of the opportunity to get a smart thermostat that lets you control the temperature from your smartphone instead.

Is Your Air Filter Dirty?

A common cause of tons of heating and cooling problems is a dirty air filter. Fortunately, it’s also one of the easiest to fix. Here’s what to do:

1. Find your system’s air filter: Check the air conditioner owner’s manual for a diagram showing you exactly where it is.
2. Get the right replacement filter: Again, the unit’s manual will tell you what size and type of air filter you need.
3. Turn off the heat pump: The easiest way to do this is to turn the thermostat switch to the “off” position.
4. Remove the old filter by sliding it out: You may have to remove a couple of screws to get at the air filter, but usually, you can just slide it right out.
5. Slide the new filter into place: Follow any “front” or “back” instructions to position the filter in the right direction. The arrows should always point to the inside of the unit.
6. Write down the date: This makes it really easy to know when it’s time to replace the filter again.

Why does a dirty air filter cause issues with the heat pump not heating? It’s because the filter starts to become clogged. This blocks air from flowing to the evaporator coil, the part of the HVAC system responsible for heating. The heat pump keeps running constantly, but it’s like there’s a wall preventing the warm air from making it inside.

It’s a good idea to replace the air filter at least every two or three months. If you have pets that leave behind a lot of fur or dander, you may want to change the filter once a month. A filter is pretty cheap, so replacing it regularly isn’t a big deal. If you need help with this, our friendly repair technicians are always happy to help, even if it’s just to tell you where the air filter is located on your unit.

Are the Unit’s Refrigerant Levels Too Low?

Both the heat pump and the air-conditioning system for your home’s HVAC need plenty of refrigerant to work correctly. During hot weather, the heat pump uses refrigerant to absorb heat from inside the home and transfer it outside. When temperatures drop, the opposite happens: The refrigerant pulls in warmth from outside and uses it to replace the cooler air inside the home.

If refrigerant levels get too low, the heat pump won’t be able to do this efficiently. You can often tell this is the case because it gets harder and harder to reach the right temperature in the home. You turn the thermostat way up but only get a little bit of heat. It’s important to call one of our HVAC professionals to fix this problem. Not only do we fill up the refrigerant again, but we also check for any leaks inside and outside the system.

Is the Heat Pump Covered?

This is the same problem as having a dirty air filter — warm air can’t get inside the home — but it’s caused by obstructions around the heat pump itself. In this case, the solution is simple: Remove whatever is blocking the heat pump, and the unit should start heating normally again.

Sometimes this happens in Florida when homeowners accidentally leave clutter around the outdoor unit. For example, maybe you were mowing your lawn and left a couple of bags of grass clippings sitting behind the HVAC unit. The truth is that after a while, even the tidiest homes in Florida can have a dirty heat pump. Dust, dirt, mud, twigs, leaves, and grass can build up on the outside.

Is It Time for a Maintenance Visit for Your Heat Pump?

At Tri County Air, we recommend a checkup for HVAC systems in Florida at least once a year. During our inspection and preventative maintenance, we look for all of these heat pump issues and check refrigerant levels automatically. That way you don’t have to worry about a thing. If it’s been more than a year since the last time your heat pump was cleaned, lubricated, and checked, schedule an appointment right away!