The Trials and Tribulations of Installing Heat Pump

A Cautionary Tale with a Happy Ending

###The Time for Change

We already had our electricity supplied via a green tariff. But with no mains gas supply to the house, our central heating and water were heated by an oil-fired boiler. As this was 17 years old and starting to give us problems, in November 2018, we decided that the time was right to look at better, greener alternatives – ideally solar panels powering a heat pump and with a home energy management system.

We had had a number of unsolicited approaches from solar panel companies, who immediately lost interest in us when we told them we lived in an AONB/Conservation Area. In addition, the fact that the back of our house faces north, made solar panels a non-starter.

Could we really reduce our carbon footprint, manage our energy consumption and also save money?

The Solution

So, we looked at heat pumps. Ground source heat pumps need access for digging equipment to the back of the property for the ground loop. This option, which is great for new-builds, also did not work as we do not have such access (the house is in the way!).

So, an air source heat pump in combination with a wireless home energy management system was the solution we opted for. (Apparently, air source heat pumps can extract heat from the air even at sub-zero air temperatures – a re-assuring feature for us, living in a notorious frost pocket.) We also decided to have separate heat pumps for hot water and central heating so that if the heating failed for some reason, we would at least continue to have hot water. The central heating heat pump would be located outside the back of the garage in the garden and the new hot water tank with built-in heat pump would (eventually) go in the garage. The separate wireless energy management system would enable us to control the temperature in each room via the internet and an app on our smartphones.

With this solution, we would no longer need to burn oil nor worry about it running out at a critical moment in winter. We would also be able to manage our energy consumption, reduce our carbon footprint and hopefully save money.

A Cautionary Tale

The products were great but progress with the installation was slow.

  • The installers seemed to have less experience of the system than they had led us to believe, and the combination of an energy management system (from a separate manufacturer) on top of the heat pump technology was entirely new to them, so they struggled.
  • It is recommended that the pump is not switched off. This means it can come on at any time. We were told the new hot water tank would not be noisy and could be installed in our upstairs airing cupboard. But it was noisy and kept us awake. So, the hot water tank had to be taken out and re-installed in the garage, necessitating a lot of additional pipes and work.
  • As a consequence, the airing cupboard had no heat source and was no longer fit for purpose. A radiator therefore had to be installed inside it to provide the necessary heat to air our clothes.
  • The central heating heat pump kept going off initially. It was never clear why this happened, but the manual re-setting required was a nuisance as we had to go outside to do this – often at night and in the cold and rain! When it was not working, we had to fall back on electric heating, tumble drying and an LPG fire, to a much greater extent than normal, causing us to incur additional cost. Finally, the unit was replaced with a different model and is working well.

It was difficult to estimate how much money we would save on our regular bills and to find out what the government’s RHI (Renewable Heat Incentive) scheme (to offset the capital outlay) would deliver, so the financial aspects were a bit of a leap of faith.

And a Happy Ending

It was a stressful experience, but after 6 months we finally had a fully operational system and are at last extremely pleased. The house is warm, the water is hot and, thanks to the home energy management system, we have control of the temperature separately in every room, via remotely controlled intelligent radiator valves.

  • The heat pump in the garden does create some noise and draught, but because it is separate from the water tank, it only comes on in cold weather when we are not in the garden, so it does not bother us nor our neighbours.
  • Also, the heat pump does not heat the water in the radiators to as high a temperature as conventional systems, so the house takes a bit longer to heat up from cold. After a bit of practice and fiddling we have got the hang of how to set the temperatures and timings to achieve the results we want.
  • We have completed our application for our grant and are waiting to find out how much money will be refunded to us every quarter for the next seven years, and to see what our on-going energy bills will be, particularly in winter, now that the system has settled down. We will update our blog when we have this information.

Mission accomplished (subject to finances). Now I must also get on with some carbon-offsetting for the stress-busting holiday we needed when it was all over!

Hints and Tips

Based on our experience, we hope the following advice will help others contemplating a switch to a heat pump. The Energy Saving Trust also has lots of information on its website about heat pumps and the RHI scheme.

Starting Off

  • Do your research. Select your products and installers carefully. Ensure the products come with comprehensive documentation/manuals etc
  • Find out whether you need planning permission.
  • During the initial survey, ensure you are clear as to the layout the installers are proposing and that it meets your requirements.
  • Find a reputable local installer with experience of this type of installation. Ask for references.
  • Ask to see a running installation and listen to the noise levels. Remember noise is more noticeable at night or if you live in a quiet area
  • Make sure you have a written agreement with the installer, as to the scope of work, so there are no misunderstandings.
  • If you need to re-position any radiators, then do this first. If you do it afterwards you will have to pay for additional and expensive coolant.
  • Identify what the maintenance requirements are and who will carry out any checks/servicing.
  • Don’t pay everything up front. Hold back part of the payment until you are happy you have a fully working system.
  • Take full advantage of the government’s Renewable Heat Incentive scheme. The onus is on you to apply for it on-line, but your installer should provide you with the technical details you need.

Heat Pump

  • Make sure you have enough space for your new water tank, including the buffer tank as well as for the heat pump itself.
  • If you have to have a water tank in your home, ensure that the installers provide some form of anti-vibration system. (Unlike conventional hot water tanks, those that operate with heat source pumps have moving parts that vibrate and create noise.)
  • If possible, have separate systems for central heating and hot water. This not only ensures you have hot water if there is a problem with the heating system, but it enables you to site the water heat pump in a location where you won’t hear it when you are in the garden in the summer.
  • Run the system for between two to four weeks to ensure it really works before parting with your final payment.

Home Energy Management System

  • The energy management system’s control panel relies on RF (radio frequency) to communicate with the heat pump, so its distance from the heat pump and location need to be considered.
  • Be aware that most of these products should be EMC (electro-magnetic compatibility) compliant, meaning they should not suffer from electrical interference. However your location and any surrounding equipment may affect this.

Good luck!


Great post @ValS. Loads of information, thanks for sharing your story.

Great post. Thanks for sharing. Could you name the manufacturers, as it might help others in their decision making?

There are 2 heat pump trade associations worth checking out: - mainly Ground Source related but a good selection of installer members, and useful background info - most of the main manufacturers belong the this assoc, a little more emphasis on air source.

One thing to consider when selecting an installer, is that most manufacturers will offer an extended warranty if you use one of their accredited installers. This incentivises installers to keep up to date with training etc, and should provide greater confidence for customers - most manufacturers will offer a search function or connect you with a local installer via their customer service team

There’s still a lot of confusion about heat pumps, but the tech is well proven. The current weakness is at the system design stage, so make sure you get a decent installer on board, with a track record recognised by the manufacturer.

1 Like

Update – December 2019

We are well into winter now and have had no problems with the functioning of our Earthsave heat pump since the initial difficulties. (Earthsave apparently no longer work with the installers we used.)

Our experience shows how important it is to get the commissioning right. An airlock in the pipes will lead to cold radiators so check for cold spots before signing off the project. Also since the water in the system does not heat to such high temperatures as traditional systems, it takes longer to get up to temperature, so a bit of tinkering with the ON/OFF timings will be necessary to ensure you get up to a warm house in the mornings.

As we’ve not completed a trouble-free annual cycle yet it is difficult to say whether we will save money compared with our previous combined electric/oil bills, particularly as we installed electric under-floor heating in our bathrooms around the same time. But the indications are encouraging we are confident we will break even at worst. Our RHI rebate arrived in October and will be paid quarterly for seven years, making a contribution of c£7,000 towards our initial outlay, or approximately 50% of our costs.

This has to be the way to go if we are collectively to reduce our carbon emissions. Despite the initial issues, I’m very glad we did it.


Hi! We’re at the initial stages of upgrading our heating and hot water. We’re also in a conservation area but we do have a southwest facing roof, but we’ve been told heat pumps are the most efficient option. The latest person we’ve got round to discuss our needs and provide a quote has said that because our house is three storeys, a ground source heat pump won’t be suitable and that it doesn’t really work with radiators - you need underfloor heating. I’d love to hear from anyone with first hand experience to share.

Ours is an air source heat pump and it works with radiators. It heats the water too. We’re very happy with it now.