To keep your heat pump from freezing, maximize airflow by regularly replacing your indoor air filters and clearing snow, leaves, and ice from the outdoor unit. Prevent icicles from dripping onto the coils by keeping gutters clear, and use your thermostat's "Emergency Heat" during extreme cold snaps.
Yes, a light layer of frost on the heat pump during winter is normal, especially in freezing temperatures. The defrost cycle should activate periodically to melt the frost, allowing the system to function well. If the frost becomes too thick, though, it can impact your heat pump's performance.
Yes. If you need to remove ice from your heat pump, hot water is a simple, easy solution. To remove ice, switch the unit off and pour hot or warm water on the frozen heat pump.
Heat pumps don't necessarily "stop working" at specific temperatures, but their efficiency drops significantly as it gets colder.
In outdoor temperatures above 30 degrees, the heat pump should cycle off and on like a normal furnace. Somewhere between 20 and 30 degrees outdoor temperature, the heat pump will reach a “balance point” where the heat needed by the home is equal to the heat supplied by the heat pump. So now it will run all the time.
There are two entirely different HVAC concepts known as the "20-degree rule" for heat pumps. The first is a user guideline that suggests setting your thermostat no more than 20∘F above or below the outdoor temperature. The second is an equipment metric referring to the system's "temperature split" or output efficiency.
If you're not sure how long it takes, try turning the heating on about 30 minutes before you need it. You should turn it off 30 minutes before you'll stop needing it. You might need to turn on your heating earlier if your home takes longer to reach a comfortable temperature.
Most heat pumps will never get down to a COP below 1, even at those temps. Lots of cold climate heat pumps are still pushing a COP of 2 at those temps. There's no need to turn the heat pump off while it's still operating. It will protect itself if it needs to.
If your heat pump is unexpectedly expensive to run, the most common culprits are inefficient auxiliary/backup heat, high local electricity rates, or a system that isn't sized properly.
Is 72 a good temperature for heat in the winter? While slightly higher than the typical energy-saving range of 68°F–70°F, 72°F still offers a reasonable balance between comfort and efficiency.
Run the Heat Pump's Fan
If your heat pump isn't operating properly, even after you've given it 3-4 hours to automatically defrost itself, then you could try unfreezing the system by turning on the fan setting (provided yours has one). Running the fan can help you thaw the heating system within an hour.
Don't Keep Your Heat Pump Running When You Don't Need It. Many people leave their heat pump running even when they're not home, thinking it's more efficient than turning it off. But running your heat pump unnecessarily can waste energy and lead to higher utility bills.
Proven basics from earlier guides remain essential:
Most systems are programmed to check for frost every 30 to 90 minutes during heating mode. If the sensors detect significant buildup, the cycle initiates. If not, it skips it until needed. This intelligent control ensures your heat pump only defrosts when absolutely necessary, minimizing disruption to indoor comfort.
If you're going to be using the heat pump, it needs good clearance above it. You could check the manual, but it's usually around 3 feet or more. If you have a different source of heat that you will be using, then it's okay to cover it with a tarp temporarily.
When it's extremely cold outside, the temperature difference is large, which makes it harder for the heat pump to transfer heat effectively. As a result, the heat pump may have to work harder and use more energy to maintain a comfortable indoor temperature, which can reduce its overall efficiency.
Heat Pump Runtime: What to Expect
On average, a heat pump runs in cycles for about 2–3 hours per day. However, this can fluctuate based on the factors listed above. During extreme weather conditions, your system may run continuously to maintain a comfortable environment.
This is especially true if your house has a heat pump. Heat pumps are most efficient until temperatures fall below 30 degrees outside. Once the temps dip below that, heat pumps can't run as efficiently to keep up with the cold, and backup electricity often kicks on.
Your heating and cooling system is by far the biggest energy consumer in your home. Air conditioners, furnaces, and heat pump HVAC systems work hard to keep your home comfortable year-round, but they also account for almost half of your energy bill.
Most heat pumps should complete about two to three cycles per hour, with ten to twenty minutes of downtime between each cycle. If you notice your system cycling too frequently or not enough, it could indicate an underlying issue that needs attention.
Myth: “I should switch to emergency heat when temperatures drop below freezing.” Truth: Even in subzero temperatures, your heat pump can draw warmth from outside air and is still more efficient than electric resistance heat. Your system will automatically use backup emergency heat when necessary.
What are the disadvantages of a heat pump?
In most homes, Heating and Cooling (HVAC) systems drive the highest energy costs, accounting for nearly 40% to 50% of your total electricity bill. Following these, the appliances that run up your bill the most include water heaters, refrigerators, and laundry machines.
Known for his practical tips, Lewis introduced the '4pm rule' which involves using curtains strategically to retain heat. He suggests opening curtains when the sun rises at around 8:30am to let in natural warmth, and closing them by 4pm to keep the heat inside.
For most customers, we recommend turning on your furnace when the weather is consistently below 18° Celsius, which usually happens to be around the end of September, or early October. Some homeowners try to put off turning on their furnace as long as they can to save money, which is okay if you're healthy adults.