Air Source Heat Pumps

[Ecosse]

Good Morning All,

I just wondered if any Forum users have any personal knowledge of installing an ASHP. Any information, such as were new radiators required, extent of plumbing works, noise levels and of course cost, would be of interest.

Thanks.

Cliff

[john.r.davies]

I considered this about two years ago.  I engaged a heating engineer, who advised that all my radiators should be replaced with more efficient modern types, as  an air source CH  runs at a lower temp than gas.    He also said that I would need to double glaze all my windows, instead of just those in high use rooms.  The cost of all this would be recovered in the next twenty years by the benefits of air source.   I decided that benefit could be gained by whoever lives here after me.

John

[iain]

I would stronlgy recommend you talk to as many installers as possible and get first hand feedback from clients who have had their product for at least a year, preferably longer.

There are many very good companies and many more .....

 

 

[harlequin]

I have a son who lives in Norway where a heat pump is the standard form of heating, they do not use radiators in the house, the pumps supply heat to a sort of air conditioning unit which blows warm air around the house or to a heated floor system. My son has both having heated floors in the bathrooms and blown air in the living areas this is supplemented with a log burner,.

Most Norwegian DIY shops sell ASHP kits for about £3000 the last time I looked, I had a bloke give me a quote to put a heat pump into my 4 bed house and he wanted to change all the radiators plus put some bloody great steam punk contraption in the garage for the hot water and charge me the best part of  £20k. I sat down and did the maths to compair the electrical cost to run the pump and oil which I currently use and surprisingly at the time oil was cheaper. It's a different story now ofcourse but I would still have to live to 120 years old to break even.

George 

Edited April 29 by harlequin

[trchris]

My son when he first left uni worked for ofgem l asked him about all the new technology at the time and he replied that to benefit I’d need to buy a draft free sealed new home insulated to the hilt and as already mentioned live to a ripe old age for it to be cost effective……..perhaps Miliband could pop round next time he in the area buying up land for solar farms and advise me further 

Chris

[PaulAnderson]

Heat pumps work on the refrigeration cycle like a split air conditioner but the internal unit usually feeds your radiators or underfloor heating.  Warm air versions are available but less common in the UK.  It works on a lower flow temperature than a traditional gas boiler so typically a larger surface area of emitter ( radiators) is needed to get the same amount of heat output into your rooms.  That in turn needs larger sized pipes.  But it’s not always the case as often systems are over or badly sized by plumbers in first place.  Each case has to be treated on its own merits with a measured survey, heat loss calculations and checks of existing emitters and pipe work.  Essentially, evaluating your existing installation against what a proper design says.  Lower flow temperatures also makes them ideal for supplying underfloor heating.   Heat pumps are also not very responsive to change and alongside the low flow rate means they are typically left on 24hours a day, giving a more comfortable environment all round.  And combined with off peak electricity overnight they can save money, but only just due to our high cost of electricity in the UK ( largely as its tied to the price of gas which the government are starting to split).  Comments about adding insulation etc would benefit all houses regardless of heat source.  You also do need a large domestic hot water cylinder ( sized as a heat pump can’t heat water rapidly so an adequate amount must be stored) and special controls.

As George says above, they’re common in Norway wiphich is a colder country (as are EV’s with over 95% of new car sales) so it’s not our environment stopping uptake in the UK.  IMHO it’s bad housing stock and poor training in the UK.

Theres lots of rubbish spoken about heat pumps and unfortunately lots of poor installers ( there’s a huge shortage of skilled workforce as the installation covers plumbing, air conditioning, electrical, controls engineering) about.  One good company I’ve heard of is Heat Geek and they often provide training to other companies.  They have details on their web site and have multiple YouTube videos.  There’s probably lots of other house building forums which could give you further advice.  Some utility companies are also pushing heat pumps e.g. Octopus or Ovo. Here’s a few links on heat pump discussions on an EV site Octopus pushing heat pumps

Heat pumps for all new homes

Verifying effectiveness

Buy a heat pump, solar and battery storage now

 

A friend of mine has solar photovoltaic panels on the roof of his three bedroom semi detached house, battery storage, a heat pump supplying radiators ( only a couple needed changing) and a large water cylinder, and an electric car.  He has no gas and with his solar and batteries sometimes buys electricity and sometimes sells it to the grid, with an overall net gain.  He essentially has no heating or electricity costs, runs his house and car for free and makes a small profit.  I’m quite jealous. 

 

[stuart]

8 minutes ago, PaulAnderson said:

A friend of mine has solar photovoltaic panels on the roof of his three bedroom semi detached house, battery storage, a heat pump supplying radiators ( only a couple needed changing) and a large water cylinder, and an electric car.  He has no gas and with his solar and batteries sometimes buys electricity and sometimes sells it to the grid, with an overall net gain.  He essentially has no heating or electricity costs, runs his house and car for free and makes a small profit.  I’m quite jealous. 

 

And how much did that cost him in initial investment?

Stuart.

[PaulAnderson]

Most was installed about three years ago and I don’t recall the cost, but with installation by Octopus and grants it was not a huge amount.   He’s actually added some more solar panels and more batteries earlier this year to get the current position as it was such a good return on investment.  He’s also obviously free from the Russian invasion of Ukraine and American isolation of Iran effects on world energy markets

 

There’s likely costs given in the links I posted.  You can do heat pump cost estimate calculations on Heat Geek

Edited April 30 by PaulAnderson
Added line on costs

[PaulAnderson]

I have messaged my friend who I haven't seen in a while and he says his heat pump installation including hot water cylinder, radiators cost only £1k after the grant.  Replacing his combi boiler would have cost more than that.   He paid a bit extra on top for an EDDI which apparently makes sure his solar ( costing £8.5k inc batteries & inverter) heats up his domestic hot water before before selling the surplus back to the grid.  His extra batteries haven't actually arrived yet.

Edit:  Just confirmed he thinks he got £7.5K grant for his heat pump when fitted a few years ago.  It may or may not  still be available.  He also corrected me in that he actually had all of his radiators replace in the work.  Most were however just replacing a single panel type for a single finned or a double of the same physical size, so no great amount of work or disturbance to the house.

IMHO a heat pump alone can be touch and go on savings but definitely a win on carbon emissions.  If you can afford them then combined with solar and batteries they're a great idea.

As for the EV, there’s price parity in several new cars, but always best to buy used or lease.  They can be a tenth of the fuel cost of an ICE if charging from home (or free in my friends case) as all but long journeys would be.  There is price parity if using most public chargers on a long journey though Tesla chargers can be half the cost.  And servicing of an EV is a fraction of the cost of an ICE too.  He’s had it several years as as has another friend of mine with his EV.  Both are saving maybe a couple of thousand a year in running costs.

 

 

Edited May 1 by PaulAnderson
Info on grant added