

Why Is My Heat Pump Not Heating My Home Effectively?

John Turpin is our resident home service repair expert here at Service Direct. He’s got the knowledge and experience to help homeowners like you make sense of most home repair issues. And with Service Direct, we connect you with top-tier service professionals to help with any repairs needed.
Don’t Panic When You Find Your Heat Pump Isn’t Working Properly
You’ve been wondering for days, “Why is my house not warming up?” There could be a number of reasons why a heat pump is not heating up home properly, from clogged air filters to thermostat issues. Understanding these possible causes will help you resolve the issue and restore your heat pump’s ability to keep your home comfortable.

What Is a Heat Pump?
Before we talk about how to fix your malfunctioning heat pump, let’s get to know the basics of how it works. All heat pumps work the same—they don’t burn fuel to create heat, but simply transfer it from one place to another instead.
Air-Source Heat Pumps
Air source heat pumps move heat from the air outside your home to the air inside. This type also comes in two different types—ductless and ducted air source heat pumps. Ductless heat pumps have a tiny hole that helps connect the indoor and outdoor units. On the other hand, the ducted heat pump has a central unit that cools or heats your home through ducts.
Ground-Source Heat Pumps
Instead of the air outside, ground source heat pumps move heat between the ground outside and the air within your home. It follows the same principle of transferring heat energy from one place (outside air) to another (inside air) in heating mode. Heat pumps work like AC in cooling mode, absorbing heat from the indoor unit to release through the outdoor unit.
Over time, the efficiency of heat pumps decreases. The problem is it can be difficult to diagnose the problems it may have for many reasons. As such, it’s a great idea to be familiar with the possible reasons why a heat pump is not heating the home, as discussed below.

Possible Reasons Why the Heat Pump Won’t Keep Your House Warm
Dirty or Clogged Filters
Air filters in the heat pump system help trap dust, dirt, and debris to maintain good indoor air quality. Over time, these filters can become clogged, restricting airflow and reducing the system’s efficiency. It should help to check and clean or replace the air filters every one to three months, depending on the manufacturer’s recommendations.
Lack of Maintenance
Regular maintenance is crucial for ensuring the optimal performance of your heat pump. Schedule annual maintenance with a professional HVAC technician to clean and inspect the system, identify potential issues, and optimize its efficiency. Regular maintenance helps extend the heat pump’s lifespan and ensures you won’t have to worry about the heat pump not heating up your home, along with other issues.
Outdoor Temperature Limitations
Heat pumps work by extracting heat from the outdoor air. However, as temperatures drop, the amount of available heat in the air decreases. In very cold climates, the heat pump’s efficiency may decline, and it may struggle to provide sufficient warmth. Some heat pumps have backup heating elements, known as “emergency heat” or “auxiliary heat,” which can supplement the heat pump’s output during extreme cold weather.
Incorrect Thermostat Settings
Double-check your thermostat settings to ensure that it is set to the correct heating mode. Some thermostats have multiple modes, such as “heat,” “cool,” “auto,” or “off.” Make sure the thermostat is set to “heat” and the desired temperature is selected.
Improper Sizing
The size of the heat pump is essential for efficient heating. An undersized heat pump may struggle to meet your home’s heating demands, leading to insufficient warmth. Conversely, an oversized heat pump can cause frequent cycling, leading to energy waste and reduced efficiency. Consult with an HVAC professional to ensure your heat pump is properly sized for your home’s heating needs.
Our resident home repair guru, John Turpin, has provided a list of common reasons heat pump may be struggling to heat your home, as well as some clever expert advise on what to do next.
Blocked Outdoor Unit
The outdoor unit of the heat pump houses the condenser coil and compressor. Obstructions or debris around the outdoor unit can restrict airflow, reducing the heat pump’s performance. Regular maintenance should prevent this, so check and clear the area around the outdoor unit to ensure proper airflow and efficient operation.
Refrigerant Issues
Refrigerant is a crucial component in the heat pump’s heat transfer process. Low refrigerant levels due to leaks or improper installation can hinder the heat pump’s ability to absorb and release heat effectively. If you suspect a refrigerant issue, contact a professional HVAC technician to inspect and address the problem safely.
Faulty Defrost Cycle
During cold weather, frost can accumulate on the outdoor unit’s coils, reducing the heat pump’s efficiency. To address this, heat pumps have a defrost cycle that periodically melts the frost. If the defrost cycle is malfunctioning, it can lead to a reduced heating capacity. Have a professional technician inspect and repair the defrost cycle if necessary.
Aging Heat Pump
“Why isn’t my house warming up?” It might be because you’ve been using your heat pump for years. As heat pumps age, their efficiency may decrease, and they may struggle to provide sufficient heating. If your heat pump is old and not heating effectively, it may be time to consider a replacement with a more energy-efficient model.
Ductwork Issues
Another possible reason for a “heat pump not heating up the home” is a leaky or poorly insulated ductwork. This can cause heat loss before the warm air reaches the rooms in your home. To resolve this, inspect and seal your ductwork. This way, you can prevent energy waste and improve heating efficiency.

What role does regular maintenance play in preventing heating issues with a heating pump?
Regular maintenance is crucial for optimal performance and to prevent heating issues. Annual maintenance by a qualified HVAC technician can help identify and address potential problems before they escalate. This includes cleaning or replacing air filters, inspecting and cleaning coils, checking refrigerator levels, and more.
Can extreme cold temperatures affect the heating performance of a heat pump?
Yes, extreme cold temperatures can impact the heating performance of a heat pump. As the outdoor temperature drops, the heat pump’s ability to extract heat from the outside air decreases. In extremely cold conditions, the heat pump may struggle to meet the heating demands of the space, resulting in less effective heating. It’s advisable to use supplemental heating options or activate the heat pump’s auxiliary heating feature in extremely cold weather.
Why does my heat pump switch to auxiliary heat frequently?
Heat pumps may activate the auxiliary or backup heating system, such as electric resistance heating or a gas furnace, to supplement heating in extremely cold weather. It also happens when the heat pump can’t meet the heating demand. Frequent activation of auxiliary heat could indicate that the heat pump is struggling to keep up with the heating requirements.
Can the size of my heat pump affect its heating performance?
Yes, the size of a heat pump can significantly impact its heating performance. An undersized heat pump may struggle to heat your home adequately, resulting in insufficient temperature control and discomfort. On the other hand, an oversized heat pump may frequently cycle on and off, leading to inefficient operation and potential temperature fluctuations.
Hire a Local HVAC Pro
Promptly addressing HVAC potential issues and ensuring proper maintenance can improve your heat pump’s efficiency and keep a comfortable and energy-efficient home throughout the heating season. If you encounter persistent issues, don’t hesitate to call a qualified HVAC technician using the phone number or form on this page.