James Mackreides shares her insights after installing a heat pump in her house six months ago, covering everything from the noise level and size of the unit to its operating costs
We welcomed a new member into our home six months ago, along with my spouse. That is, to our garden specifically. A small brick outhouse is close by, housing a Daikin air source heat pump and its accompanying hot water cylinder, which are now situated beneath the kitchen window.
It's a significant addition because it replaces an old boiler that heated and supplied hot water to our Edwardian terraced house in north London.
Approximately 6,000 was the net cost of the heat pump, which was paid for in interest-free monthly installments because we were eligible for a 7,500 government grant under the Boiler Upgrade Scheme (BUS).
For us, installing the heat pump was the most stressful aspect of the large renovation, but many others found it to be the most fascinating feature.
What are the dimensions, appearance, and sound characteristics of a heat pump? Will it actually lower your energy costs and keep you warm during the winter? These were only a few of the inquiries from loved ones. In all honesty, our builders and architect were also intrigued.
Heat pumps are still an underappreciated garden feature, even though electric cars are now frequently seen on UK roads. Just 1% of UK homes had a heat pump in 2023.
As more and more homeowners apply for the BUS grant, the number keeps growing each month. According to the Department for Energy Security and Net Zero, 4,028 applications were received in March 2025, an increase of 88% over the same month the previous year.
Although they are even less common than air source heat pumps, the BUS also includes 7,500 grants for ground source heat pumps and 5,000 grants for biomass boilers.
According to the Heat Pump Association, just under 100,000 heat pumps were sold in the UK last year, including those that were not subsidized by the government.
That being said, this falls far short of the government's goal of 600,000 annually by 2028.
Approximately half of households would be content to switch from gas boilers to heat pumps if doing so would result in lower energy costs, according to a recent Heating Trades Network UK survey.
These lessons, which I learned from having a six-month-old heat pump, may help you decide whether to install one.
1. Although installing a heat pump in an older home is challenging, it is not impossible
New-build properties have a lot of heat pumps installed, which is probably quite easy. However, replacing a fossil fuel heating system, such as a gas boiler, is more difficult to do in order to qualify for the 7,500 grant.
The first step is to schedule a survey, which can be obtained from an energy provider such as Octopus Energy, British Gas, or EDF. To obtain a variety of quotes, I would advise having several completed. You can also discuss things like whether you'll need new radiators, what size heat pump they recommend, and more.
EDF owns CB Heating, which is what we chose. It might have made the installation simpler because we were remodeling our entire house. That did, however, require us to work with our energy provider Octopus, as well as our plumber and builders, to coordinate CB Heating.
Among the problems we encountered were: a snag where the electricity meter needed to be changed before the heat pump could be installed (which caused us a lot of chasing); the need to pay an additional £1,000 for large water pipe connectors (which weren't evident in the heat pump survey); and the hot water cylinder dilemma (should it be placed in the kitchen or the loft? How far away from the heat pump? Our architect made multiple plans to include where it could go). The outhouse is where it ended up. ).
2. Heat pumps are large but not noisy
The cost of our heat pump might have been covered by now if I had a pound for each time someone inquired about its noise level!
It's not noisy, I assure you. We have never heard it in the house, and it's right next to the kitchen window. You occasionally hear a low whirring noise outside. like the gas boiler or refrigerator's white noise.
However, the size is larger than I had anticipated. Our model is 1 m long, 460 cm deep, and 870 cm high. If the heat pump could be flush with the kitchen wall, it would appear less bulky, but there must be room around it for airflow.
I'm glad we decided on that specific location, and I've grown accustomed to it, so please consider where to put the heat pump.
In her garden, James Mackreides stands next to a heat pump.
James Mackreides clarified that because there needs to be room for airflow, her heat pump cannot be mounted flush to the wall.
3. There will be disagreements as you try to figure out how to operate your heat pump
Gas boilers and heat pumps are not the same thing. It is only half the battle to install one; the other half is to figure out how it operates.
It's common knowledge that turning off radiators in rooms you're not using and turning off the heating when you leave are two ways to reduce energy costs. Heat pumps, on the other hand, are designed to maintain a constant temperature throughout the house because they must work much harder to warm it up again when they are turned off.
As a result, my husband and I have been fighting a lot to get the heating just right and to obsess over our energy use (and Octopus app bills).
To get advice and support from heat pump experts and owners, as well as to resolve any disputes, I suggest joining the Heat Pumps UK Facebook group.
4. Take your time looking into energy tariffs; there are many options
Next up is the real cost of maintaining a heat pump. The majority of energy providers give heat pump owners a special tariff. We have three electricity unit prices based on the time of day, and we are on the Octopus Cosy tariff.
The plan is to have the heat pump activate during the least expensive hours, which for us are 4 a.m. to 7 a.m., 1 p.m. to 4 p.m., and 10 p.m. to midnight. Additionally, the radiators will remain warm all day. During these budget-friendly times, we also turned on the dishwasher and washing machine.
No matter which provider installed your heat pump, you can compare rates to find the one that benefits you the most. As an illustration, Scottish Power offers a Heat Pump Saver tariff with a discounted rate from 11 a.m. to 4 p.m.
5. It's too soon to tell if my energy bills will go down
Fortunately, our house is much warmer now that we have upgraded our radiators and replaced our outdated, inefficient boiler.
But as of right now, it doesn't appear that we are saving money. For instance, both this year and last year (when we still had the gas boiler), our February energy bill came to about 160.
According to studies, a heat pump can save you anywhere from £100 to over £500 annually. Although I've already mentioned that we're still getting used to our six-month-old heat pump baby, it worries me that we haven't seen any savings yet. Hopefully, we'll learn to use it more wisely and take advantage of the Cosy tariff.
I might post a note in my diary to compare the yearly cost when our heat pump turns one, and I might ask the Facebook group for any additional energy-saving advice that I've overlooked.
Leave a comment on: Here are five things I've learned since installing a heat pump in my house