Common Winter Heat Pump Problems & Solutions | Troubleshooting Tips


Common Winter Heat Pump Problems & Solutions

First of all, what is a heat pump? Basically, instead of a furnace, which typically uses natural gas to create heat for the home, a heat pump works like an air conditioner in reverse, absorbing heat from the outdoor environment and transferring it into the home. If you are wondering how a heat pump extracts heat energy from the cold air outside, consider the 2nd Law of Thermodynamics, which states that heat flows from hotter to colder bodies. When the temperature of the refrigerant that flows through the outdoor condenser coils is lower than the temperature of the outside air, it is able to pick up heat and transfer it indoors.

Since Sacramento and the Bay Area experiences mostly mild temperatures throughout the year, heat pumps are an energy-efficient alternative to separate furnace and air conditioner units. While heat pumps can struggle to work efficiently when temperatures dip below freezing, since we mostly experience moderate weather, heat pumps are ideal for homeowners around the Bay Area. Heat pumps generally save homeowners money in areas that don’t experience extreme hot and cold temperatures.

A heat pump is one system that functions as both a heater and air conditioner, saving you space and energy. If you own a furnace and it is nearing the end of its lifespan, consider an energy-efficient heat pump. Since heat pumps are also central air units, they can work seamlessly with your existing ductwork. Keep in mind that there are also ductless mini-split heat pumps which don’t use air ducts. To find out if a heat pump is right for you, get in touch.

Winter Heat Pump Problems & Solutions

Not Enough Heat

If you are a new heat pump owner, you may be surprised that the heat generated by these systems isn’t as strong as the heat generated by furnaces. This is normal. While the heat may not be as intense, heat pumps generally distribute heat more evenly throughout the home.

They will run longer and at a more sustained level, meaning less turning on and off and no more cold/hot spots and strong gusts of air.

Due to the difficulty in extracting heat from very cold outdoor environments, some heat pump owners need a supplemental heating system to feel comfortable. Many people supplement heat pumps with space heaters or some sort of adapted furnace, boiler, or oil burner system. Speak with the heating professionals at Service Champions if you are not receiving enough heat from your heat pump.

Outdoor Unit is Iced Over

If your outdoor condensing unit is iced up, airflow will be severely restricted, resulting in a struggling unit that may end up causing severe damage. If there is light ice, it should go away soon, but if the ice remains for a significant period of time, it’s a problem you want to address quickly.

The most common solution to a frozen heat pump is running the defrost cycle. It normally turns on automatically at timed intervals or when the unit detects frost, however, some systems have a defrost option. The defrost cycle basically reverses the heat pump into air conditioning mode so that it can pump heat to the outdoor unit until it unfreezes. Don’t worry, the defrost cycle only runs for around 10-15 minutes.

Since you don’t want cold air blowing on the coldest of days, many heat pump owners opt for a supplemental heat system. This usually means electric resistance heat strips, which keep the air warm. After around 15 minutes, the heat strips will turn off and the heat pump will come back on.

If you are outside when the heat pump goes into defrost mode and reverses the refrigerant flow, it may sound as if something is wrong with your unit. Don’t worry, it’s just the defrost cycle.

If the defrost cycle isn’t thawing your iced overheat pump, try these steps:

  • Check the air filter and replace if needed. Clean air filters improve airflow as well as indoor air quality.
  • Make sure there is no large debris near the unit that may be preventing airflow. Always maintain a minimum 2-foot clearance around the entire unit. Periodically trim back encroaching plants and clean your outdoor heat pump unit.
  • If there is no air flowing from your vents, you may have a malfunctioning blower motor. Try setting the thermostat to “fan” to see if the blower motor or some related component is at fault.
  • If the indoor blower assembly is working, the outdoor condensing fan motor may be the culprit. Make sure your heat pump is on and then check the outdoor condenser unit—the fan should kick on.

The buildup of ice on your condenser unit is never a good sign. If the solutions above do not work, prevent any further damage to your unit by contacting a professional right away.

Constantly Running Heat Pump

It’s possible that too much cold air is getting in the house for the heat pump to keep up. When was the last time you winterized your home? It’s not too late.

Here are some tips for keeping the expensive heat in and cold air out:

  • Make sure your doors and windows are closed and well-insulated. Check for air leaks around the perimeter of your doors and windows. If there is air movement, replace the weatherstripping.
  • Inspect insulation levels, especially in the attic.
  • Double-paned storm windows are expensive, but can help retain heat. For a cheaper solution that also adds interior beauty, use energy-efficient thermal curtains to improve window insulation. You can also use cellular shades to allow light in while still getting the benefits of added window insulation.
  • Use draft snakes.
  • You may need to caulk around draft leak and improve basement joist and attic insulation.

Learn more insulation and air sealing solutions.

No Air or Cold Air

Make sure all of your vents are open to allow proper air movement. It’s never a good idea to close vents and registers in the home to try and keep the heat in one area of the home. This “manual zoning” solution may seem smart at the time, but it can create unwanted pressure within the system and cause duct leaks, system failure, and other problems. Your HVAC system, ductwork, and vents/registers have been specifically designed to match your home. Leave them all open, all the time.

If you are feeling cold air blowing from the vents, the heat pump could be in defrost mode (mentioned earlier). This is normal if you don’t have a supplemental heating system, such as heat strips. Defrost cycles normally last around 10-15 minutes and then the heat will kick back on. If you want supplemental heat strips or they aren’t working, don’t hesitate to contact us.

When to Call for Professional Heat Pump Service

  • The outdoor unit is not running at all.
  • The thermostat isn’t working properly.
  • There is a problem with refrigerant flow (you may have a leak).
  • Ice/frost remains on the unit for over half a day.
  • You haven’t scheduled annual heat pump maintenance. Remember, schedule professional heat pump maintenance at the beginning of every heating season, preferably in early autumn.

Schedule your heat pump tune-up today! If you have any questions about heat pumps, don’t hesitate to contact Service Champions.

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