Air Source Heat Pump Outlet Temperature

A heat pump transfers heat from the outside air into your home, making it an efficient and cost-effective method of heating and cooling. However, the output of an air source heat pump will vary depending on the outdoor temperature and the setting of the thermostat.

So, how hot should the air from the heat pump be? In heating mode without auxiliary heating, the average temperature output of the heat pump is 85°F to 92°F. Typically, a heat pump in heating mode will create a temperature difference of 15-20°F above the current air temperature. The air temperature of a heat pump varies with the age and condition of the heat pump.

This article will further explore some of the questions you may have about heat pumps and their use. Read on to learn more about how to use a heat pump and save on your energy bills!

The average heat output can be 85-92°F; however, the temperature of the heat pump output depends on several factors, including the age and condition of the heat pump. New heat pumps with R410a refrigerant can extract more heat from the outside air, increasing output.

At what temperature should the AUX heating start?

Heat pumps use refrigerants and heat exchangers to extract heat from the outside air, even in cold weather. Below 30 degrees, however, they lose a lot of efficiency and need help keeping up with the thermostat.

So, how much temperature will the Aux heat turn on? When the outside air temperature drops below 30°F, the heat pump will automatically activate auxiliary heating. The heat pump will also use emergency auxiliary heating in heating mode if the thermostat raises the temperature by more than 2°F.

For example, if the outside temperature is 40°F and the indoor thermostat reads 67°F, setting the thermostat to 74°F will enable auxiliary heating to help reach the desired temperature of 74°F as quickly as possible. In heating mode, the heat pump will use emergency heating to help reach a comfortable temperature as quickly as possible.

Since heat pumps use outside air, they often need help heating your home when it's cold. Due to this feature, AUX heat comes into play at low temperatures. To understand the optimal temperature for AUX heating, you must first understand how it works.

What is AUX heating?

Heat pumps extract heat from the outside air to heat your house, which works well in the warmer months but can be difficult to do in colder weather. Unfortunately, when the air freezes, not enough heat is extracted from the outdoor air to heat your home without help. The heat pump brings in less air than the building loses heat. In this case, you need AUX heat to meet the demand.

Auxiliary heat (also known as an auxiliary, supplemental, or emergency heat source) can be a gas furnace or hot plate backup that turns on to help the heat pump heat the home when the temperature drops below 30°F.

Auxiliary heat helps the heat pump compress the heat to keep you warm in cold weather.

It must be understood that auxiliary heating is not used. In summer, you can spend months without AUX heat and relying on a heat pump.

Depending on where you live, auxiliary heating is usually used during the cold winter and late fall. Northerners will use their AUX heat more often, but if you live in the warmer South, you can usually avoid it.

Finally, auxiliary heat works with your heat pump to separate it from emergency heat.

Auxiliary, Standby and Emergency Heat: Is there a Difference?

Many people confuse auxiliary heat, backup heat, and emergency heat. There's no real difference between the three, it references the same components inside the heat pump. Auxiliary heating, backup heating and emergency heating use the same hot plate or gas furnace to supplement the heat pump to heat your home.

The difference between auxiliary heating and emergency heating is simple: the emergency heating setting on the thermostat allows you to bypass the heat pump and use only the hotplate. Aux heat combines heating strips and heat pumps to automatically heat your home without you having to do anything.

In addition, the auxiliary heating will automatically turn on at a certain temperature. If there is a problem with the heat pump, homeowners should manually turn on emergency heating. If emergency heating automatically turns on, your heat pump may be damaged or damaged.

Emergency heat explained

Emergency heating can be turned on when your heat pump is not working or damaged. This setting causes your thermostat and heating system to automatically draw heat from your secondary heat source, which could be a furnace or a hotplate. Heating strips are located inside the indoor air handler and heat the air before it enters the ductwork and is then distributed through the house.

When using emergency heating, your heat pump will not. In general, emergency heating is used to warm your home if there is a problem with your heat pump or if it cannot adequately heat your home.

At what temperature should AUX Heat be turned on?

Your auxiliary heating should turn on when the outside temperature is close to 30°F and below. This temperature is when your air source heat pump struggles to get enough heat from the outside air to warm your house. So when the temperature is below 30 degrees, AUX heat is needed to supplement your heat pump.

When this 30 degree temperature is reached, your AUX heating should automatically turn on - you don't need to do it manually. If your auxiliary heating is on when the weather is warm, you should contact a professional to help you find the problem.

What temperature should I set my heat pump to in winter?

When manipulating thermostat settings in winter, we encourage homeowners to set the heat to the lowest temperature they can handle. This will be different for everyone.

Ideally, the most energy-efficient setting for winter is to set the temperature to 68°F and keep the thermostat alone. If you need more warmth, increase the temperature by 1° until you find your ideal comfort setting.

Are you considering a dual fuel heat pump? See our article Are Dual Fuel Heat Pumps Worth It? What do you need to know.

As I discussed, air source heat pumps operate by taking energy from the surrounding environment and raising the temperature for heating or lowering the temperature for cooling. The greater the difference between outdoor and indoor air temperatures, the less efficient the heat pump system will be.

This inefficiency can cause your heating system to burn more energy and increase your energy bills. Fundamentally, the best way to reduce inefficiencies and avoid high energy bills is to close the gap between your outdoor air temperature and your thermostat.

Frequently setting your thermostat to high temperatures, especially in winter, can exacerbate energy losses in your home and increase your energy bills.

However, in the cold winter months, when you want to stay warm, setting the thermostat on low isn't an option. Fortunately, getting the heat pump at the right temperature can help reduce energy bills and maximize the efficiency of the heat pump.

For maximum comfort and efficiency, you should set your thermostat between 68 and 72 degrees Fahrenheit. This temperature is comfortable for most people and keeps everyone warm with typical clothing while minimizing heat loss.

When no one is home, setting your heat pump between 58 and 62 degrees Fahrenheit allows you to save on heating bills without worrying about making your family cold or uncomfortable.

There are a wide variety of heat pump thermostats on the market. A programmable thermostat will manage the temperature settings for you. A programmable thermostat is a digital thermostat that helps you pinpoint temperature readings with minimal guesswork.

In recent years, smart thermostats, such as Nest or ecobee, have used advanced artificial intelligence technology to manage indoor comfort. Smart thermostats can even learn based on the environment. These heat pump thermostats are great for maintaining a constant temperature in your home.

Should a heat pump run continuously in winter?

While heat pumps are less effective at freezing and sub-freezing temperatures, they can technically operate continuously in winter without the help of auxiliary heat. However, to save money and energy, you shouldn't run your heat pump continuously in the winter -- always turn it off when not in use.

For example, if you're going to be away overnight or throughout the day, you can turn off the heat pump and set a timer to turn it back on before you return. If you set the timer to turn about half an hour before you get home, it should be warm when you arrive.

Ultimately, turning off the heat pump as much as possible will maximize energy savings. If your main concern is saving money during the winter months, you can even set your timer so that your heat pump turns off for a few hours at night when you go to bed, then turns it back on before you wake up!

Will the heat pump work in defrost mode

Finally, if you see ice on your outdoor unit, your system may be in defrost mode. The heat pump may temporarily go into defrost mode to avoid freezing. If you see ice on the outdoor coil, defrost mode must melt the ice to prevent system failure.

In defrost mode, the emergency heating plate (or gas backup furnace) and heat pump can run simultaneously to maintain an even room temperature. The indoor unit senses that the air temperature is too low; emergency heat or furnace will replenish while the defrost cycle heats the outdoor coil.

The outdoor coil needs to be kept free of ice to prevent damage to the fan motor and compressor inside the outdoor unit.

In conclusion

Overall, the heat pump should be about 20 degrees warmer than the outside temperature in heating mode. When it's too cold outside and your heat pump can't keep up with your heating needs, auxiliary heat will supplement it to keep your home warm.

This is often necessary during winter months when the heat pump is less efficient and you should set the heat pump between 68 and 72 degrees Fahrenheit (20 and 22 degrees Celsius) to maximize energy efficiency.

Lastly, don't leave your heat pump running continuously in winter or your heating bills will be higher - try turning your heat pump off when not in use.