Hi All

I am looking for someone who can re quote for an ASHP install. I have had a quotation and signed a contract but my new self build is taking so much longer than I anticipated and I am not convinced I a getting the best service so I think I would like to look again at installers. I have had a BUS voucher granted but it is beyond 6 months since it was offered and so I think it has expired so before I go ahead I would like to explore options. 
My house is a new build double timber frame with very high insulation and MVHR. It is ideal for a simple heat pump system and I have already got the UFH installed on the ground floor. 
Thanks

Did you try using the find an installer tool in the site? 

@jimseng 

Hi, I'm not sure what area you are in but after lots of research including the use of this site, I have settled on Urban Plumber. A number of other installers including Octopus and Aira presented problems and what seemed like very generic proposals. Urban Plumber provided a very detailed and what seems like a well designed option. Only problem is the length of time you have to wait for installation, but that seems to be the price of quality Installers.

@mkz, that's very helpful. Even if Urban Plumber are not available wherever @jimseng is, positive recommendations like yours are absolutely front dead centre of what this forum is about.

After an intense recode, I’m pleased to announce that we’ve just launched a drastically rebuilt version of the RHH Installer Finder (which you’ve probably seen scattered across the site, including the sidebar here on the forums) and I wanted to share what went into it and why I think it’s a significant step change from anything else out there.

The thing that’s always bothered me about how heat pump installers are rated online (Google, Trustpilot, Checkatrade, take your pick) is that the rating almost always reflects how someone felt on the day they left it. Usually shortly after the install, when everything’s fresh and the installer has just nailed the handover. That’s the moment you capture. Not the heat loss calculation. Not whether the proposal was accurate. Not the quality or timeliness of the work itself. And certainly not the call six months later when the house is cold and nobody’s picking up. Rating a heat pump installer is not about a single snapshot in time!

We’ve had thousands of conversations on this forum about what actually makes a good installation. The answer is always the same… it’s never one thing. It’s how an installer behaves across the whole journey, from the first email to the support call in January when the system isn’t performing as it should.

So that’s what we’ve tried to build. A finder that draws on our own leads and direct homeowner interactions, rather than a star rating someone typed into a box at the finish line.

The methodology is entirely ours. I’ve spent weeks fine tuning it. We’re not publishing the scoring model and we’re not disclosing the criteria to installers. That’s intentional… and at the same time I think it’s the most honest attempt at this problem anyone in this sector has made. I’m biased obviously.

The full finder with all its bells and whistles is available here: https://renewableheatinghub.co.uk/reliable-heat-pump-installer-uk

The Chicken and the Egg (maybe?) :

I was not inclined to consider a Heat Pump - usual stuff : we have an old house, fairly large, some of it decently insulated, some less so, but not wishing to wring out whatever character hasn't been removed by previous owners. Although not listed, we don't want to massively modify the fabric of the house and risk damp, kerb appeal and so on.

Anyway, of late, and largely on the back of Trump and whatever despots come next, I started to seriously consider moving from oil to a HP - £9,000 from the Government being a decent incentive too. 

Our EPC was done by the previous owner and is 13 years old. It gives a D (56). A fair bit of work was done by the previous owner as well as us since then and I suspect that we could just about scrape a C - maybe even be a comfortable C. Much would depend upon the EPC surveyor.

Can I get installers interested? No ! :

It seems like Heat Geek see us as about as efficient as a bonfire and dismiss us as soon as we enter our details on their calculator. 

Aira were supposed to visit today but one of their quality assurance people cancelled our meeting, in part because the heat loss was considered too high for their 12 KW HP - which is fair enough as the house is about 280 square metres. Other installers say we are too far away (again fair enough). One independent installer calculated our heat loss using their on line tools, as 25 KW. Another claimed 28 KW. Others whom I have approached via their contact pages have simply not responded. One came out over a week ago and has still not provided an estimate. Perhaps he will, perhaps that trail is cold too.

Perhaps it's a function of where we live (in the middle of Devon) but there are few installers to begin with and even the installers listed on this site are "emerging". It seems like all of the good ones, understandably, are chasing the low hanging fruit.

Given the expertise in the installer market, or lack of it, it's a huge risk going with somebody who doesn't have a track record.

For what it's worth - I spent a good many hours learning how to use HeatPunk and then exhaustively entering details about our house and carefully choosing the U values, many derived by custom wall thickness measurements and checking fabric. HeatPunk suggests a heat loss of about 12 KW - that's on -2 to +21 temperature range. Our oil usage averages 1250 litres per year (we run our house at 18-19 degrees) (underfloor heating in most of it) and the installer who visited estimated the heat loss to be in the region of 12-14. .... but I'm still waiting for a budgetary estimate from him!

Would paying for a new EPC make any difference to installer interest do you think? How quickly do new EPC's appear on databases that installers interrogate? Or is the size, age and perception of what out house is, always going to put installers off?

thanks

Posted by: @ian33a

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Would paying for a new EPC make any difference to installer interest do you think? How quickly do new EPC's appear on databases that installers interrogate? Or is the size, age and perception of what out house is, always going to put installers off?

Its not necessarily always going to put installers off, you need to shop around in the market, different installers have different approaches and some routinely overestimate losses and/or avoid 'difficult' houses.  Whether a new EPC would help or not I cant say,  it cant do any harm.

Its well worthwhile getting a better handle on your loss if possible.  The heat punk exercise is a good start.  Ventilation loss is however often overestimated, particularly for older houses, what ACH did you put in/did it assume.  Also solid stone walls, if you have them, are apparently also regularly overestimated.

This is where fuel consumption also comes in, particularly with houses like yours that have a great deal of fabric uncertainty.   Assuming a house doesn't cool too much at night, gas consumption, which is easy to establish, can give a pretty accurate read out of loss, probably better than any survey.  Its actually how I sized my heat pump for a property that is smaller than yours (200sq m) but likewise has patchy fabric upgrades.    The smarter installers took the data I had on board, and did the calculations that they are obliged to do 'in the light of this data'.  That's how I ended up with a 7kW heat pump instead of the 16kW that the two full surveys I had, each involving 3 hours in the house, indicated.

Oil consumption is generally not so well measured as gas (I had half hourly gas meter readings to go on) but still gives an indication/sense check.  Given what you have said about the house an oil usage of 1250 l/year (12,500kWh/yr) is surprisingly low.  If you heated to 20 consistently this would suggest a loss of 6kW max, really more like 5kW.  If its 18 most of the time (ie it doesnt cool much at night) then that would bump the estimate up to perhaps 7kW. 

Are you certain of the usage and how does 12,500kWh compare with what the EPC says?  FWIW my gas consumption in a 7kW house was 18,000kWh/year.  I would say that getting to the bottom of this is essential before you proceed, I would even think about putting some logging on the oil usage, deferring a season, heating consistently and getting some more data if you cannot reconcile heat punk with the oil usage because this degree of uncertainty is simply not conducive to good system design.

If you can get some data of your own (and possibly a new EPC) I would submit it to installers (with a summary) and your enquiry.  The better ones will take notice and engage with the facts, you dont want to talk to the others anyway because they are too obsessed with the protective fiction of the fabric survey.  

BTW with UFH already in place it should be a pretty simple install and you should get very good efficiency.  Have you also got a DHW tank and if so what size and type?

Happy to advise further.

Posted by: @ian33a

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Perhaps it's a function of where we live (in the middle of Devon) but there are few installers to begin with and even the installers listed on this site are "emerging". It seems like all of the good ones, understandably, are chasing the low hanging fruit.

As quick comment on the network, the Emerging status you're seeing isn't a reflection of installer quality. Every single installer in the network starts at Emerging, including our Vetted installers. It is simply the baseline level before verified homeowner feedback begins to accumulate through our system. As installers complete jobs and homeowners submit feedback through Renewable Heating Hub, their Confidence Score progresses through Recognised, Established, Strong and Exceptional.

The network is still in its early stages and we are building that feedback record now. The Emerging label will look very different in six months as real data comes in.

On the Devon coverage point, you are right that it is thinner than we would like and the coverage gaps you are seeing are exactly what drives our installer recruitment. If you do find someone good locally who is not yet in the network, please do point them our way.

@jamespa I used an ACH of 0.5 in most rooms aside from two (both of which have wood burners) where I used 3.5 - I went with what was suggested in HPunk (if I recall correctly).

We don't have gas - being rural, the village has no gas main - all we have is oil - I based an estimated HL (independently from HeatPunk) based upon oil usage averaged over four years and this gave a figure not a million miles away from HeatPunk. We actually run our house at 18-19 degrees so I ran an option in HeatPunk with those temperatures so as to cross correlate. The figure that I wrote in my entry above is -2 to +21 and is probably more aligned to what an installer would use in a HL calculation.

@editor I do appreciate that emerging isn't a poor reflection of quality, simply a lack of track record on this site. Ironically, where we used to live, the area was rife with high quality installers with exceptional track records ..... moving into the sticks has many upsides but a high density of good installers isn't one of them !

Posted by: @ian33a

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We don't have gas - being rural, the village has no gas main - all we have is oil - I based an estimated HL (independently from HeatPunk) based upon oil usage averaged over four years and this gave a figure not a million miles away from HeatPunk. We actually run our house at 18-19 degrees so I ran an option in HeatPunk with those temperatures so as to cross correlate. The figure that I wrote in my entry above is -2 to +21 and is probably more aligned to what an installer would use in a HL calculation.

Sorry I missed that when I first read your post, May I recommend you re-read my post above as I added some information to it, which I am pretty certain crossed with your response.

Your oil consumption suggests a loss of 7kW which is way different to the Heatpunk results.  IMHO, you need to get to the bottom of this discrepancy before proceeding.  Do you use the wood burners much and how did you get to an estimate of 12kW based on fuel usage?  You are right that installers will design to room temperatures 18 (bedrooms) - 21 (living rooms), its mandated in the MCS rules.

@jamespa No problem, that you are willing to discuss far outweighs any crossing of information through the web!

I'm sorry, a moment of old age stupidity - our annual usage averages out at 2513, not 1250. I'd made a calculation mistake several weeks ago and corrected it but then misread the latest data - so, twice what I said originally ! what a numpty !

We have an oil boiler, feeding two manifolds and sixteen circuits over two floors. These circuits are shared through ten zones - all of the zones have electronic thermostats, all running at the same temperature profile (so, somewhat, a single zone) and with a two degree set back at night. The DWH and UFH water comes via a thermal store (which would likely go were we to move to a HP). We have two lounges which, daftly, only have wood burners. One of these burners is lit almost every evening during the colder months. The other is occasionally lit if we use that room. Both burners are rated at about 5KW. All other rooms have UFH.

In the first year or we lived here, the room thermostats were mechanical and with no set back capability. They were clicking on and off like a tap dancer! The oil usage on the worst days back then was around 17 litres per day (but monthly measurements taken and averaged). The worst months in 2025/26 were averaging around 14 per day following replacement of thermostats and some extensive automation using Home Assistant to try to use energy sources based upon Agile spot pricing and solar forecast - so the data is slightly skewed because of home improvements.

With the installer who visited, we suggested adding a radiator in one of the lounges to take the edge of the cold away and reduce the need for a wood fire each night. He said he would probably have to add radiators in both lounges in order to keep MCS happy - which is not an issue for us. His ball park HL estimate was about 14 KW - as I say, we still await an estimate quote from him.

@ian33a

Ah 2513 vs 1250 makes a big difference.  Roughly how many evenings and for how many hours do you reckon the log burner is on for in a year.  If we then assume 5kW and add it to the yield from the oil  we should get a total heat input.  Divide that by 2900h and you get your core heat loss estimate  If you separately divide the total by 3000h and also separately by 2000k, these give two useful limits in addition.  However but this is based on 20C room temp.

Im guessing your daily average room temp is perhaps 17.5.  If we assume that the average OAT in the heating season is 7, then thats a deltaT inside vs outside of 10.5 as opposed to  13, so if you multiply the figures you got in the previous calculations by 13/10.5 you more or less correct for that.  If thats consistent with 12kW then you have reconciled things, if its not then there is still a bit of working out to do.

Annual consumption is a bit rough and ready, but good enough for a sense check which it sounds like you have already done.  Better is to plot consumption vs degree days (or average OAT), easy with gas, more challenging with oil however you may need to get some logging going and do that if you want to convince many installers.  That said the 14kW guy sounds potentially sensible.

Posted by: @ian33a

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The DWH and UFH water comes via a thermal store (which would likely go were we to move to a HP)

Its possible to use a thermal store with an ASHP to supply DHW but its generally inefficient so rarely advised, because you have to heat to a high temperature to get a good volume yield.  That said if its volume exceeds your daily hot water requirement it may be worth doing the calculation.  There is a lot of industry focus on replacing the DHW cylinder, but the business case, particularly if you heat dhw on off-peak leccy, rarely stacks up.  The better installers are realising this and now do not always replace the cylinder.  Of course there may be other reasons to do so.

Presumably the water that passes through the UFH is mixed down (a lot!) from the thermal store temperature.  You wont want to be doing that as I am sure you realise.  Direct from HP to UFH no mixing!