A window heat pump lives a double life. In the summer, it gives you all the cold air you need while reducing interior humidity. In the winter, the whole system works in reverse to give you warm air instead of cold. How does it do that? Let’s find out.

What is a Window Heat Pump?

A window heat pump is a device that provides a dual source of heating and cooling. As the name suggests, it is mounted in a window frame. It allows the room or space to benefit from cold air in the summer and warm air in the winter.

How Does a Window Heat Pump Work?

A window heat pump operates in either air conditioning mode or heating mode. As an air conditioner, it removes warm air from your room and transfers it through a coil that contains refrigerant gas. This process extracts the heat and expels it outside, and then circulates chilled air back into the room. As a source of heat, the window heat pump works in reverse, drawing in air from the outside and passing it through the coil and refrigerant to warm it. This heated air is then transferred into your room.

Is a Window Heat Pump Energy-Efficient?

Cooling Efficiency

A typical window heat pump is measured for its air conditioning efficiency in two different ways: Combined Energy Efficiency Ratio (CEER) and Energy Efficiency Ratio (EER). The two are different because the EER gets measured against the air conditioner working while the room temperature is at a constant 95 degrees Fahrenheit. The CEER also factors in the power the unit uses when it is switched on but non-operational. For that reason, the CEER is slightly less than the EER. There is another rating called SEER (Seasonal Energy Efficiency Rating), and this is applied to split and central HVAC systems. The Department of Energy (DOE) introduced CEER in 2014 as the new standard, but many window heat pumps and air conditioning units still show the EER values.

Heating Efficiency

When in heat mode, window heat pump performance is measured by the Heating Seasonal Performance Factor (HSPF). The HSPF is calculated by dividing the seasonal BTU by the amount of energy used over an identical period. Heat pumps are required to have a minimum HSPF of 7.7, but some heat pumps have an HSPF of 13, making them very efficient. To qualify for the Environment Protection Agency (EPA) recognized Energy Star status, a rating of 8.2 is needed.

What Size Window Heat Pump Do I Need?

The capacity of your window heat pump depends on the number of BTUs, more commonly known as British Thermal Units. To calculate a BTU, or a unit of heat, you need to see the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. This tells you how capable your window heat pump is at removing or adding heat to the room. The Higher the BTUs, the more potent the heat pump. Once you’ve decided on the BTU capacity, you then need to factor in the climate where you live. Colder states like Alaska will require less focus on cooling and more on heating. The reverse is true of Florida.

Is A Window Heat Pump Loud?

Window heat pumps typically have an operating volume of about 65 dB. To give you a point of reference, normal conversation in an office or restaurant registers at roughly 60 dB. So, you will hear some noise, but it shouldn’t be unbearable. And after a while, you will hopefully get used to it. You may even find it a soothing source of white noise. Just as with window-mounted air conditioning units, window heat pumps have a fan and compressor situated inside the unit. These two elements make the most noise. Split and central systems have the compressor mounted outdoors.

Why Choose a Window Heat Pump?

There are many reasons why you might opt for a window-mounted heat pump. The first is that it is the cheapest option when compared to split and central HVAC options. Not everyone has the cash to burn, but everyone deserves to be cool in the summer and warm in the winter. Plus, if you live in a smaller space like a mobile home, a window-mounted heat pump might have all the capacity you need. Why pay for more significant and more thirsty systems when it is unnecessary? According to the most recent US Census, 36.6% of households live in rented accommodation. This figure is close to the 1965 high of 37%. So, if you are one of the 36.6% and you want a source of heating and cooler air, a window heat pump could be your best option. It is affordable, easy to install, and best of all, it causes no damage to the building. Plus, not everyone lives in a house, with approximately two in 10 Americans living in apartments or condos. According to the 2010 census, there were 194.3 million adults living in the US, between the ages of 18 to 64. So, if you do the math, that equates to over 38 million people living in apartments or condos. If they want to benefit from the heating and cooler air, the simplest option available to them is a window heat pump.

Window Heat Pump Cost

You should expect to pay about $500 for a basic model. For a more advanced window heat pump, the price can quickly jumps to over $1,000. The 9k BTU 9.9 EER Amana Heat Pump Window Unit is an excellent example of a window heat pump, and it starts at less than $850. If you want the top model in this range, it will cost you over $1,100. But you are getting cooling and heating in one. Window heat pumps cost more than window A/C units because they give you double the value.

What to Look for in a Window Heat Pump

Washable Air Filters - These filters are reusable, which means you don’t have to pay for expensive replacements, and they are better for the environment because nothing goes to the landfill. By having a washable filter, not only do you get more cooling air circulating inside your room, but you also get fresher air. Programmable Timer - This gives you the ability to set and forget. Once you have programmed your timer, the heat pump does the rest. So, there will be no more walking into a cold room when you get back from work. The heat pump can kick in while you are on your commute home. CFM - This stands for Cubic Feet per Minute, and it is a measure of the heat pump’s capacity to circulate air. The higher the CFM, the fresher and cooler the air is in the room. 50 CFM should be enough to handle rooms of 1,000 square feet, but the 9k BTU 9.9 EER Amana Heat Pump Window Unit has a CFM of over 500, so it is easily up to the task. Remote Control - Everything else is remote controlled these days, so why not your heat pump? You’ll never have to leave your armchair again. Well, maybe to go to the bathroom. WiFi Controls - There seems to be an app for absolutely everything, so why not for your window-mounted heat pump. Controlling your heat pump from a smart device is the ultimate in convenience. Fan Only Option - Some heat pumps allow you to just run the fan to circulate air in the room. This saves energy and money, a bit like an eco-mode. Ball Bearing Motors - They are quieter and more efficient.

Final Thoughts

Window heat pumps are a great all-rounder. They heat, cool, and filter the air in our rooms and spaces. Window-mounted heat pumps are easy to install and relatively inexpensive to buy when compared to central HVAC systems. They are ideal if you want to avoid the expense of retrofitting ducting and pipework, and if you live in a small space or apartment, they are the heat pump of choice. A window heat pump might be your next best purchase!