People do not need to turn their heat pumps off. Residents should make sure their supplemental home
In general, heat pumps can run continuously in winter without wasting energy. They can maintain a consistent indoor temperature efficiently.
Heat pumps do not operate as efficiently when temperatures drop to between 25 and 40 degrees Fahrenheit for most systems. A heat pump works best when the temperature is above 40. Once outdoor temperatures drop to 40 degrees, heat pumps start losing efficiency, and they consume more energy to do their jobs.
Most standard heat pumps will function at 100% efficiency until the outside temperature reaches about 40° F. However, when the temperature dips below this, most heat pumps are not able to maintain efficiency. They become much less effective at temperatures between 20° F to 30° F.
This heating method works incredibly efficiently until the outdoor temperature reaches about 35 degrees. At this point, the heat pump has difficulty extracting enough heat from outside to keep up with the thermostat setting. This is when many people assume it's time for switching their heat pump to emergency heat.
As long as your house is properly air-sealed and insulated, an air-source heat pump can perform well beyond temperatures of -13 degrees Fahrenheit!
Your auxiliary heat, or secondary heat source, should come on when your heat pump is struggling to heat your home effectively. The thermostat will trigger auxiliary heat when: The outside temperature is below 40 degrees or a set aux heat trigger temperature. The heat pump is in defrost mode.
Lockout controls minimize use of strip heat, maximizing energy savings. Incorrect lockout settings result in the majority of inspection failures. PTCS Spec: Set auxiliary heat lockout to 35°F or lower.
According to the Department of Energy, 68°F is the sweet spot that balances comfort and energy efficiency during the fall and winter months. When your home is occupied and when family members are awake, a heat pump setting of 68°F keeps the living areas reasonably warm.
If freezing has already occurred, shut off the unit (keeping it on could damage the unit) and pour water over the unit to melt the ice (do NOT attempt breaking up ice with heavy tools!). In addition, check to make sure no damage has been done to the copper coolant lines, this might be a job for a professional plumber!
When temperatures dip below 40 degrees, the heat pump is designed to run almost constantly to keep your home comfortable. So, if the weather outside is particularly cold and your system is running constantly, don't worry. It may mean it's working as it's supposed to.
Don't turn your mini-split systems off during cold weather. Cold Climate Heat Pumps are meant to run almost continuously and many systems work below zero degrees. While it may seem like they cost more because they run more, it's actually the opposite!
Rebate-eligible heat pumps can reach over 400% efficiency in mild temperatures and can maintain well over 200% efficiency even into negative temperatures. This is why turning off a heat pump in frigid temperatures and opting to use a fossil fuel boiler or furnace instead is a mistake.
If possible, keep a 2-foot space around the unit clear. Install a cover: Look for a heat pump cover that's durable, weather-resistant, and breathable. This will help protect your unit from snow, ice, dirt, debris, and animals. This cover also provides shade in summer, thereby increasing energy efficiency.
Gas furnaces produce air that is 130-140°F range. So 85-92°F feels cold to new heat pump owners. Your body temperature is around 98.6°F (everyone's body temperature is slightly different, but that's the average). Since heat pumps produce air that's below that, it can feel cold to you.
The break-even point is usually around 15 degrees. Your heat pump will still work below freezing and below 15 degrees. It will continue to perform below 0 degrees or colder. It just won't be as efficient over those very coldest days of winter as using a gas-fired furnace.
This is where emergency heat comes in. Typically, this setting on your thermostat kicks on when the temperature is anywhere between 30 to 35 degrees Fahrenheit. How your emergency uses this air differs from the normal way that your heat pump usually functions.
For this reason, heat pumps start to lose efficiency at around 40 degrees F and become less efficient than furnaces at around 25 degrees F. Heat pumps continue to be effective at cooling the indoors, even at high temperatures. In the South, it rarely gets below 25 degrees.
This can cause concern, as auxiliary heat typically is not supposed to run all the time. While it's normal for auxiliary heat to kick in during exceedingly cold temperatures, running it too long may indicate an issue with the heat pump.
The auxiliary heat setting on an HVAC unit usually turns on when you need heat fast. If this secondary heating system is constantly running, it may mean that the weather outside is very cold or that the thermostat is set higher than normal. It's also possible that a part of the heat pump is malfunctioning.
“Auxiliary Heat On” is just your thermostat's way of saying, “I'm working extra hard to keep your home warm because it's really cold outside.” It's a team effort between your heat pump and the auxiliary heat, and they're both there to make sure you stay comfy during those chilly days.
Heat pumps operate most efficiently when holding a steady temperature. Turning heat pumps down when you're away or asleep may actually use more energy than leaving them on. The reason is that they have to work harder to come back to the desired temperature than they do to maintain it.
Tip #1: Turn the heat pump temperature up.
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).
Auxiliary Heat – This is the secondary heat source that turns on automatically. Emergency Heat – This is when you turn on the secondary heat source.