Finding the chase and cutting to it

Our heat pump is a year old (ASHP, air sourced heat pump).  Its present was a service.

Now, at this point, I remember every annual boiler service being a good £170 plus what-ever parts were needed and the cost of fitting them – largely opaque on the invoice. Last year, when the boiler died, it was barely 13 years, and our plumber thought that was beyond its expected life-span!

The ASHP should last 15-20 years. Transparency is the word here with the invoice we got. From pressure rebalancing to filter replacements, everything was listed and priced. A bit more, £218 including VAT, which is a bit more than a gas boiler service, but it should be something we can budget around.

You mug!

To be honest, we did shop around. Olive Air had a cancellation, so the fact our previous appointment had been cancelled by the other firm meant we got our servicing completed only three days later than planned.

There is far less competition out there for the hearty band of sourced pump service engineers than there is for gas boiler engineers – hopefully that will change over time.

Whatever, I guess it’s your life…

I am really happy with the decision we made to change. Ideally, the house would have been built with it and an air to air system but this is not a bad half-way house.

We also see it as our bit to help reduce the costs of such systems in the long term. 76,000 homes had made use of the Boiler Upgrade Scheme (BUS) by May 2025 and we were one of those homes.

More people in rural areas have made use of the scheme than people in towns – the suspicion is that they have more land and home space to make the move – I have friends in London and Cambridge who don’t have room for a small hot water tank let alone one the size of ours which nestles in our garage.

Rural areas are also much less likely to have mains gas: an air sourced heat pump removes the need for a LPG or oil tank for the boiler. Ironically, the big air pump takes much less space than a big liquid petroleum gas (LPG) or oil tank!

Of course, it is not the only way to move from gas or oil central heating to an electrically powered system. Let’s do a quick summary of what is out there. I am going to talk about efficiencies in terms of x00% – which means for every unit of electricity (1kWh) you put into the systems, how much “heat power” do you get out – 300% efficiency means you get out 3kWh of heat for every 1kWh you “buy”.

Bear in mind, a very efficient gas boiler gives 80% efficiency, or for 1kWh you buy you get 0.8kWh of heat.

Electric storage heaters:

Convert 100% of the electricity into heat. Teamed with an electric immersion heater, this is a very simple way to get heat into your home.

They work by getting warm for a short period then dissipate the heat until the next heating period.

The immersion heater can be powered from solar diverters: when you are generating more solar power than you are using, the solar diverter sends the electrons to the immersion heater rather than a grid – think of it as a water heating battery! We are on our second one.

Traditionally, you would power your heaters from the grid over night and enjoy the heat over the day. If your house is well insulated, or you work from home, this is a great solution, more efficient than a boiler any day of the week.

With home solar power, this is not how to work the system. Get the storage to heat during the day off your solar heat and give off heat once the sun goes down. Free electricity to heat when the sun is shining.

(Ironically, most solar cells work best when it is cold).

Air sourced heat pumps:

With efficiencies of between 300% 400% over the winter, and 600% to 700% over the summer, this is a good option if you have radiators in situ.

They work by using a heat exchanger to take any “heat” out of the input air, and using that to heat either water or air, depending on your heating system type.

If you don’t have radiators in your house already, an air to air system allows you to have hot air pumped through your house during the winter and cold air during the summer. Used a great deal in America, houses are built with vents which allow the air to be pumped through. In the USA and Canada, these systems are called “Heat and air”. It is really unusual in the UK.

Teamed with a well insulated house, an air to water system sends cooler water than a boiler does round the house. Weirdly, you heat for longer in the day but it costs you fair less.

The air pump can also heat stored hot water. During the summer, we have spent very little to have hot showers and lovely baths during the summer where we haven’t used our solar.

People occassionally ask about noise, but even in the rooms near the pump or standing outside by the pump when it is going, it is very quiet.

Water or Ground sourced heat pump:

These work on a similar principle to the air sourced heat pump but use coils of water or another fluid sunk in a body of water or buried in your property’s garden.

Very expensive to put in after the building has been constructed, and may need planning permission.

The efficiencies used to be much higher than any air sourced heat pump, but I think these still out perform an air sourced system in the winter, delivering between 300% and 500% efficiencies. Expensive to buy, cheaper to run.

When the coils need replacing, a ground system can be expensive to do too.

Infrared panel heaters:

Like storage heaters, the efficiencies are not as high as heat pumps but out perform boilers dramatically, at nearly 100%.

Unlike storage heaters and radiators or air vents, infrared panels heat objects, like your walls and you! So long as your home is shielding from wind, that means the produced heat is enjoyed by you and insulation performing a subtly different function.

The panels can be ceiling mounted too, freeing up wall space.

I have friends who did this recently and can confirm, as a guest, I couldn’t tell the difference on a cold December day.

If I was moving into a house which hadn’t had radiators or under floor heating, I would definitely consider this as an option. It could be done as a DIY tasks, too. Here is a quick walk through by a supplier: infrared heaters complete guide top recommendations for 2025.

An immersion heater is then used for hot water.

That’s all well and good, what if I don’t have a water tank for an immersion heater!?

Condensing boiler system do not need to have a hot water tank, and in some homes, that allowed space to be freed up. Going back to having one is not an option for everyone.

So what do you do instead? I’m sure we’ve all seen the restaurants, cafes, and bars which have “instanteous water heaters” for the hot water tap – you don’t have a traditional tap but a box with a dial and there are a few seconds before you get hot water through.

All in all, one thing becomes clear, if you want to make the move, you can.

I would seriously consider whether you generate your own electricity, and if you do, what your appetite is for your total cost of ownership. Heat pumps are not just high purchase and installation costs. Servicing is required for complex machinery.

I am looking at my friends battery, solar, and infrared heaters as a good way to go, potentially done over a long period of time until you can be gas or oil free… the final step would be to get the individual water heaters.