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Man standing next to a heat pump in the cold weather of Vermont.

Managing Mitsubishi Heat Pumps In Very Cold Weather

With below-freezing temperatures in our area, homeowners are asking what they can do to make sure they are getting the most from their heat pumps to keep their homes warm.

Even cold air contains some heat and with Mitsubishi Electric’s renewable heat pump technology, this heat can be captured even when temperatures fall well below ZERO. For homeowners who have made substantial energy improvements to their homes and installed heat pumps in locations intended to cover the whole home’s heating needs, your heat pump can continue working to keep you cozy and warm.

As winter marches on, we want to take this time to remind you of a few tips to get you through these chilly days. Please keep in mind these tips are intended for people operating a zero energy home without supplemental heating options. If you have a supplemental heat source, you may want to use that.

Mitsubishi Heat Pump Tips

Tip #1: Turn the heat pump temperature up.

76 degrees F is not too warm! Remember, you are trying to heat the whole house from one location. You do have to overheat the room(s) with the heat pump in order to make enough heat for the rest of the house. The colder it is outside, the bigger the temperature difference will be between the core of the house (with the heat pump) and the other rooms (without the heat pumps).

Tip #2: Manually turn the fan speed to high.

Most likely, the heat pump will not kick into high fan speed on its own – it’s just the way the programming is set. To get the maximum heat out of the heat pump, move maximum air through the heat pump head. This will be noisier so you may wish to only turn the fan speed up when you leave the room.

Tip #3: Do not turn the temperature down in order to save energy.

You need the heat pump to give you everything it’s got, and that includes every minute of the day. At these temperatures, the heat pump capacity is noticeably lower. Don’t restrict your heating to just part of the day, because there won’t be enough hours in the day to deliver the heat your house needs. Keep the temperature at or above your comfort temperature all of the time.

Tip #4: No need for extra ventilation.

When it’s cold, you’re getting extra natural infiltration due to the difference in buoyancy between the inside air and outside air. Therefore, you probably don’t need to add extra ventilation for fresh air. If you typically leave a window cracked, close it. And if you have a ventilation system, put it on low speed or off for a day or two.

For customers with a heat pump water heater, we recommend you use the electric resistance mode. Remember, a heat pump water heater is an air conditioner in your basement. Usually, the house can handle that extra bit of cooling, but when it is extremely cold outside, you want every Btu of heat to be available for your comfort. The water heater can get its own heat from electric resistance without impacting the air temperature of the house. Keep it in resistance mode until it stops impacting your comfort. Just because the basement is cold doesn’t mean your comfort is impacted. However, if the water heater actually makes your living spaces uncomfortable, leave it in resistance mode. At the latest, turn it back to heat pump mode on April 1st. Some years you may never need to put it in resistance mode.

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Thinking of Going Solar?

Reduce your reliance on fossil fuels by adding a solar array to your home. Learn moreContact us today for a free site evaluation and quote.

Is Your Home Ready for the Upcoming Winter Heating Season? 

Start with an energy audit to learn how you can improve the comfort of your home with air sealing, insulation, and ventilation. Contact us to learn more.

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