10 Common Questions about Heat Pumps

Think back to your last dinner party with your “cool” friends — were you embarrassed because you didn’t know enough about heat pumps? The answer depends on the type of crowd you hang around with!  We won’t judge...

But really, if you are researching heat pumps or rely on a heat pump for year-round home comfort, you may have some questions. Here are ten questions that often come up:

1. How do I know if I have a heat pump or an air conditioner?

Are you ready to do some simple detective work? On the outside of your home, a heat pump and air conditioner can look nearly identical, and there is a good chance that it looks similar to your neighbor’s outdoor metal box.  Although a heat pump provides both heating and cooling to your home, there is a simple way to determine if you have a heat pump by testing the unit in heating mode. 

From your thermostat or control system, turn the “heat” ON. Once you feel the heat coming from your return vent, head outside to observe that metal cabinet. If it is operating and you don’t pay a gas or propane bill, you most likely have a heat pump! Case closed!

2. When do I need to schedule maintenance for my heat pump? 

Since your heat pump is designed to heat and cool your home, it may be operating year-round.  Depending on your climate, it’s a good idea to schedule a cooling checkup in the spring and a heating maintenance service call in the fall. Many dealers offer pre-season specials on inspection packages during their typical slow times of the year. 
Seasonal preventive maintenance on your heating and cooling system may guard against many unexpected failures and could maximize the lifecycle of your heating or cooling unit.1  So, if you have determined that you have a heat pump (see #1), be sure to schedule  pre-season maintenance.

3. Is a heat pump better than an air conditioner?  

Both a heat pump and an air conditioner are designed to cool your home using the refrigeration cycle. To determine if one provides improved performance over another, you have to compare the particular size, cooling features and efficiency ratings. 
But if your home needs a heat source, a heat pump can pull double duty — cooling and heating your home year-round.  Your air conditioner is designed just to keep your home cool!

4. Why isn’t my heat pump keeping me comfortable?

When installed, heat pumps are sized for your home according to specific calculations. If a heat pump is  a wrong size, it may not keep you comfortable in your home. Oversized units may create bursts of warm or cold air, tricking thermostats or control systems into shutting off the system before the entire house reaches the desired temperature. An undersized heat pump may not be able to generate the cooling capacity required for your space. 

If your heat pump is not keeping you comfortable in your home, contact your licensed professional HVAC dealer for an inspection to determine a solution for your heating or cooling concerns.

5. What is the lifespan of a heat pump?

It’s tough to determine the actual lifespan of a heat pump because there are many factors that contribute to its overall performance — maintenance schedule, filters changes and proper installation are just a few. Location and operational hours may also impact the longevity of a heat pump. For example, if you live in an area with long, cold winters, a heat pump will run more than in temperate climates. The same goes for warmer climates. 

If you are looking for peace-of-mind, be sure your installation technician provides a limited warranty for their work  and is qualified, experienced and recommended by a trusted source.  Additionally, research the manufacturer’s available limited warranties, registration requirements and coverages for your specific heat pump. 

6. If the temperature falls below freezing, should I manually turn ON my thermostat’s emergency or auxiliary heat switch?

As long as you are comfortable in your home, there is no need to manually switch on your heat pump’s auxiliary or emergency heat switch on your thermostat or control system.  The auxiliary heat will kick on if the heat pump needs additional heating capacity to meet your set temperature.  If you find that you continually need additional warmth in your home, contact your local, licensed professional HVAC dealer for a consultation.   

7. Do I have to cover my heat pump in the winter?

No, do not cover your heat pump in winter! To function properly, a heat pump needs to pull in the outdoor air through the side vents and exhaust through the top of the unit. If you cover your heat pump, it may not operate as designed and may cause damage to the system.  

8. Is it normal for my heat pump to have frost on it? 

When it’s cold outside, the outside  of your heat pump may become develop a coating of frost or light ice. Don’t be alarmed! When this happens, the defrost control senses it and automatically starts a defrost cycle. During this period the auxiliary heat strips are automatically activated to warm the indoor air.

However, if you notice a heavy coating of ice, contact your licensed professional HVAC dealer as soon as possible. Heavy ice accumulation may indicate that your heat pump needs servicing. 

9. What’s the difference between SEER and HSPF on a heat pump?

SEER and HSPF are the efficiency ratings assigned to a heat pump.  The SEER (Seasonal Energy Efficiency Ratio) measures the efficiency of a heat pump in cooling mode.  HSPF (Heating Season Performance Factor) measures the efficiency of a heat pump in heating mode. The higher the SEER and HSPF number, the more efficient the unit is designed to be in heating and cooling mode.  

10. Why are some rooms colder or warmer than others?

Your HVAC dealer should have properly sized your heat pump for your specific home during installation.  If your heat pump is not sized correctly, it may not be able to generate the capacity required for your space or shut off before the entire house reaches the desired temperature. 

But if your heat pump is sized properly, your home may have a duct issue. A poorly designed duct system may results in poor airflow, leaving some rooms colder or warmer than others.  If your ducts aren’t sealed properly, or an air leak goes undetected, airflow may pass through your system unevenly. To properly determine the specific cause of a warm or cold room, contact your licensed professional HVAC dealer.



1 Maintaining your Air Conditioner. n.d. <http://energy.gov/energysaver/maintaining-your-air-conditioner>.