Air Source Heat Pumps: The Pros and Cons

What are air source heat pumps?

Air source heat pumps (ASHPs) are a low-carbon technology that provides efficient heating solutions for homes and businesses. There are two types of ASHPs distinguished by how they distribute their heat: through air or water.

How do air source heat pumps work?

Both types of ASHP draw in outside air over a network of tubes filled with very low-temperature refrigerant, which reacts to the warmer air. This gas then passes through a compressor at pressure, forming into a hot liquid. The hot liquid then passes through a heat exchanger, which draws out the heat for your hot water and heating circuits.

An air-to-air heat pump transfers the outside air directly into your premises via a fan system to heat the space. In contrast, an air-to-water heat pump transfers the outside air via your central heating systems to heat radiators, underfloor heating, and provide hot water.

A heat pump system can provide all the heat your premises needs while running at much lower temperatures than a gas boiler, thereby reducing your energy bills. This is assuming you have adequate insulation in your property and that the ASHP has been sized correctly.

So, what are the pros and cons?

Advantages of air source heat pumps

Low carbon energy solution

The main advantage of air source heat pumps is how they are more environmentally friendly than fossil fuel boilers running on gas or oil. While they use electricity, they are a much more carbon-friendly solution and the installation of solar PV panels can offset the running costs.

Low maintenance

Any type of heating system requires maintenance to keep them running as efficiently as possible. Air source heat pumps are no different, but it really is a low-maintenance solution and generally needs the occasional cleaning. Typically, this includes wiping down the coils, replacing the filters, removing dirt from the internal blade fans, and cleaning the registers. Because the unit is installed outside, it’s also important to ensure nothing obstructs the heat pump.

Grants

At the time of writing, there is an upfront cost of around £15,000 for an average-sized air source heat pump for an average house. The good news is that small businesses (and homeowners) in England and Wales may be eligible to receive £5,000 off the cost of a new pump, thanks to the government’s Boiler Upgrade Scheme. As detailed on the government’s website, you’re eligible for a grant if all the following are true. You must:

own the property you’re applying for (including if it’s a business, a second home, or a property you rent out to tenants)
have installed (or plan to install) your new heating system on or after 1 April 2022
be replacing fossil fuel heating systems (such as oil, gas, or electric)

In addition, your property must have a valid Energy Performance Certificate (EPC) with no outstanding recommendations for loft or cavity wall insulation.

Longevity

As with any heating solution, it is only as good as how well it is maintained. Typically, a well-installed air source heat pump system can last for around 20 years. If you regularly maintain it, though, it could last even longer, making it a worthwhile investment.

Disadvantages of air source heat pumps

Upfront costs

As we’ve already discussed, air source heat pumps carry a nett upfront cost of around £10,000, and so that cost needs to be factored in, especially if your business is not eligible for a grant. It’s likely that the upfront cost will decrease over the course of the decade, but the grants may not exist then!

Running costs (don’t forget about offsetting with PV)

Heat pumps run on electricity, which is roughly three times the price of gas, but the average heat pump is at least three times more efficient than a gas boiler. That means that ASHPs do cost a little more to run, but because of their efficiency, it’s not as high as you’d think. It’s important to get advice from a certified provider, such as Practical Energy Solutions, before you make any firm decisions. Make sure the ASHP is sized correctly.

It’s not carbon-neutral

Because ASHPs rely on electricity, they aren’t always green, and they’re certainly not carbon-neutral. That said, they are much more sustainable than oil, coal, and gas heating systems.

Property suitability

In order to get the most out of air source heat pumps, the property has to be suitable:

Large radiators: to get the same heat output as a fossil fuel system, radiators for ASHPs need to be twice the size of normal ones
Hot water cylinder: there needs to be space for a large hot water cylinder inside the premises. The size needed will be determined by the size of the premises
Insulation: the premises must meet standard requirements

Summary

There are many advantages as well as some disadvantages to air source heat pumps. If you’re looking for a solution which is sustainable and efficient, heat pumps are ideal. If the cost will be an issue, it’s probably worthwhile looking at an alternative, such as solar panels or biomass.

Ready to harness the power of air?

If you’re considering investing in an air source heat pump solution for your business, we can help. From initial consultation to design, installation, and ongoing maintenance, our team of expert energy technicians can support you at every step of the process, ensuring a seamless transition to sustainable energy solutions that align with your business goals and values.