Why Is My Heat Pump Blowing Hot Air In Cool Mode?

image of a homeowner keeping cool with fan due to heat pump blowing hot air in cooling mode

Heat pumps are very versatile. Unlike other types of HVAC systems, a single unit can cool or heat your home, per your preferred settings. Therefore, you receive comfort year-round. If it is too cold in the winter, use your heat pump to warm your home. On the other hand, when the temperatures rise in the summer, the same unit can cool your home. You can switch modes and change temperature settings easily. However, there might be times that you find your heat pump blowing hot air in cool mode. Read on to determine the reason behind this issue.

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Why Is My Heat Pump Blowing Hot Air in Cool Mode?

Heat pumps are made durable, but they are not invincible. A faulty heat pump’s common issue is blowing warm air during the cooling cycle. Therefore, it is recommended that homeowners familiarize themselves with the usual culprits. Learning more about why this heat pump problem happens will minimize the chances that this problem will happen again. They can conduct simple heat pump troubleshooting before calling in the experts to perform advanced solutions. Here are seven issues that might be causing this specific heat pump problem:

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A Broken Heat Pump Reversing Valve

heat pump operation

The main component behind the heat pump’s versatility is its reversing valve. The setting will dictate whether it will collect heat outdoors and bring it inside or gather the heat indoors and release it outside. The valve directs the refrigerant flow to reach the temperature settings. A broken reversing valve means that the heat pump won’t work as it should. This broken component needs to be replaced. Additional refrigerant should also be added to the system. Make sure to have a trained HVAC expert help you with this complex task.

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Heat Pump Thermostat Problem

modern programming thermostat for heat pump

The heat pump behaves like this in many situations because the thermostat was programmed incorrectly. The heat pump might have been set so that only the fan runs, causing it to blow warm air throughout the house. Check the thermostat settings to ensure that it is in cool mode. Someone might have accidentally changed the setting, so you need to tweak it. It could also be that the thermostat has low batteries, so replace them with new ones. You may also check the breakers if they tripped.

If the issue persists, you might have a malfunctioning thermostat. All you can do then is replace it. Old manual thermostats may need replacing anyway, so use this opportunity to do so. Purchase a basic model of a programmable thermostat. Keep in mind that greater features are available if you are willing to spend a little bit more money.

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Heat Pump Refrigerant Loss

Heat pumps don’t generate their own heat as furnaces do. Instead, they utilize a coolant to collect the heat from one place and let it out in another. A heat pump that has insufficient refrigerant will not do its job properly. The thermostat setting may be right, and the reversing valve works well, but low refrigerant levels mean the heat pump will still blow hot air even in cooling mode. This issue is likely caused by a leak. Hire a licensed technician to repair all leaks and top up the coolant right away.

Clogged Air Filter On Heat Pump

image of a dirty heat pump filter

Air filters trap dust and dirt. These settle on the filter’s surface while air passes freely. However, the dirt layer can get so thick that the air passage is blocked. The heat pump operation becomes strained when the airflow is restricted. This problem can be resolved when the air filter is cleaned. Replace the filter with a new one to get a fresh start. Read the manufacturer’s manual to determine the filter’s cleaning and replacement frequency. Remember that the environmental conditions where you live may require you to change the filters more frequently.

Heat Pump Duct Leak

Air ducts can break down as it ages like everything else. If you have old ducts, they may start to leak air. This prevents the proper distribution of conditioned air throughout the home. As a result, some homes feel warm, and others feel cold. It can be challenging to pinpoint the exact location of the leaks. Contact HVAC experts to help you resolve this problem. This way, there will be improved air distribution, reduced energy use, and lower monthly bills. Repair the ductwork immediately to achieve long-term comfort and savings.

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Dirty Heat Pump Coil

The heat pump’s outdoor unit will likely have dirt and debris. Consider the dust level in the environment, grass clippings, dried leaves, and pet hair, among others. These factors can certainly make the heat pump coil dirty after some time. This layer of dirt limits the heat pump’s ability to collect and release heat via the coils. Therefore, the outdoor unit should be regularly cleaned. Use a water hose at low to medium pressure to get rid of loose dirt. High water pressure can damage the unit, so be mindful of the settings. Use a light brush to scrub off stubborn spots.

Clean indoor coils as well. They are harder to access, so leave them in the capable hands of an HVAC technician. Heat pump maintenance services are affordable and yield excellent results.

Frosted Indoor Coil On Heat Pump

ice on coil cooler of dirty heat pump

Consider the possibility that a frosted indoor coil is a reason behind the heat pump malfunction. It may sound illogical that a frosted coil results in warm air in cool mode. However, it is perfectly logical if you know how a heat pump works. Freezing happens when the water in the air condenses around the indoor coils due to low temperatures. The ice prevents the coil from gathering heat, so the unit doesn’t work as it should. To repair this issue, the heat pump requires some downtime before setting it in fan mode. This way, warm air is pushed through the coils, and the defrosting process goes faster.


Do I Repair or Replace the Heat Pump?

Homeowners may be curious about when they should repair their heat pump or replace it entirely. Here are several factors to consider before making a final decision:

  • Heat Pump Warranty: Check the system’s warranty. If it is still under warranty, use it for free component replacements and labor fees. It makes sense that you keep using the unit at least until the warranty ends.
  • Heat Pump Age: Heat pumps can last for ten years or more. Unfortunately, there’s a higher chance that they succumb to wear and tear once they reach the 10-year mark. HVAC repairs will be needed more often, and many homeowners don’t want to deal with this hassle. If you want a dependable system, purchase a new heat pump.
  • Heat Pump Repair Vs. Heat Pump Replacement Cost: It is advisable that you compare the cost of repairs and the price of a replacement. Include the repair bills you spent in the last few years and an estimate of future repair costs. Buying a new heat pump may be cheaper than keeping your old one.
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Heat pumps make your home comfortable in any season. It can blow warm air when it’s cold and vice versa. However, you need to investigate if it blows hot air while in cool mode. The reason behind it is probably one of those included in this list. Contact an HVAC professional for immediate assistance.

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R.F. Ohl provides high-quality HVAC services in the Poconos and the Lehigh Valley, Pennsylvania. We hire only the best professionally certified and highly trained technicians who can conduct superior heating and cooling maintenance, installations, repairs, and replacements. Each of our friendly techs has the extensive knowledge and experience to service your HVAC system correctly.

Our company has the most affordable HVAC service rates in the area. Our tune-up services can increase your energy efficiency and enhance comfort while lowering your home’s energy costs. We can recommend the best budget-friendly solutions for your HVAC repair or replacement system needs. All our work is guaranteed. Book your next service appointment and call R.F. Ohl today. We offer free, in-home estimates.

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