There are 2 different ways an air source heat pump can provide heat in your home: by heating the air in the rooms or by heating the water in the central heating system, but which option is best for your home? We've compared these different heat pumps, to help you find out.
Air-to-water heat pumps
As the name suggests, air-to-water heat pumps use the ambient air outside of a property to heat the water in the central heating system. They are the more frequently seen air source heat pumps on the market, and come with several benefits and disadvantages.
Benefits of an air-to-water heat pump
Air-to-water heat pumps come with several benefits when compared to air-to-air heat pumps.
Compatible with traditional central heating systems
According to the English Housing Survey 2019-2020, 90% of households in the UK have central heating with radiators as their main heat source. That means, unless you're among the select few, you are going to want an air source heat pump that's compatible with your existing central heating system. Air-to-water heat pumps are designed with this very purpose in mind. Air-to-air heat pumps are not compatible.
Easier to install
As the air-to-water heat pumps will generally connect directly to the central heating system they are usually a lot easier to install than air-to-air heat pumps. Installing an air-to-water heat pump in a property with existing central heating is similar to replacing a boiler, whereas installing an air-to-air heat pump would require the installation of air ducts throughout the property.
Not just for heating
Although air source heat pumps are mainly considered for heating properties, that isn't the only thing they do. Air-to-water heat pumps will heat the water in your property for your central heating, but can also be combined with a hot water storage tank to provide hot running water too.
Disadvantages of an air-to-water heat pump
Air-to-water heat pumps don't just come with benefits, there are some disadvantages too.
More expensive
Air-to-water heat pumps are not cheap. Depending on the size of the unit you need and which manufacturer you pick, you could end up paying more than £10,000 for an air-to-water heat pump, excluding the cost of installation.
In comparison, you can get some air-to-air heat pumps for less than £1,000. Even if the cost of installation is high, you could still spend less on getting an air-to-air heat pump installed than you would on just buying the parts for an air-to-water heat pump.
Requires more space
In addition to the space a hot water storage tank would take up to allow for hot running water, due to radiators being required, air-to-water heat pumps still take up more room in the property than air-to-air heat pumps do. This isn't much of a problem if you already have radiators installed, but to maximize space in a new property air to air heat pumps are the better option.
Air-to-air heat pumps
In what sounds like a much simpler process, air-to-air heat pumps extract heat from the ambient air outside of a property and transfer it to the air inside of a property. If you'd like more detail on how air source heat pumps work, have a look at the following article: What is an air source heat pump?
Benefits of an air-to-air heat pump
There are several benefits to having an air-to-air heat pump rather than an air-to-water heat pump.
Heat and cool
As the air to air heat pumps is essentially air conditioning units that are capable of heating a property, they can also be used to cool a property when the weather is hot. Many manufacturers refer to them as climate control solutions because they aren't just for heating a property, they can cool it too.
Save space
Air-to-air heat pumps may require the installation of air ducts throughout the property, but once they have been installed, each room will feel more spacious. This is because there is no need for radiators which take up wall room and floor space. For newer, less spacious properties, air-to-air heat pumps could help you make the most of your space.
Less expensive
As mentioned earlier, air-to-air heat pump units are considerably cheaper than their air-to-water counterparts. Some air-to-water units can be 10 times more expensive than an air-to-air unit, which is something to think about.
Disadvantages of an air-to-air heat pump
Air-to-air heat pumps don't just come with benefits when compared to air-to-water heat pumps, there are some disadvantages too.
Not compatible with traditional central heating systems
If you have an existing central heating system and want to replace a gas boiler with an air-source heat pump, air-to-air heat pumps are not for you. As they only heat the air in a property, they cannot be connected to the central heating system and are completely incompatible.
Higher installation costs
Although like-for-like installation costs for both types of heat pump are generally quite similar, unless you have a property with existing air conditioning ducting, the cost of installing an air-to-air heat pump is likely to be higher as there will be more work to do.
No hot water
Air-to-air heat pumps do not heat the water in a property. This means you will need a secondary source of heat to provide hot running water throughout your home. While this is possible through solar power and other water heating solutions, it is still a separate cost that is avoided when installing an air-to-water heat pump.
Which heat pump is best?
Having learned the advantages and disadvantages of these air source heat pumps, you should now be able to make a decision on which would be best suited to your circumstances. However, as there is a lot to consider when getting an air source heat pump installed, we would recommend seeking the advice of a local heating engineer. They can ensure you get the right solution for your home's unique circumstances. Fortunately, we can help you find qualified engineers in your area, who will provide you with free, no-obligation quotes.
