Are Octopuses Slowing Consumer Adoption of Heat Pumps?

Octopus heat pumps

In the meetings and conversations I have with heat pump engineers, installation companies and others around the UK, a theme is emerging: people who are unable to get an Octopus installation drop off the journey completely and stop considering getting a heat pump altogether.

This is completely anecdotal and it would be good for the relevant entities and associations to do some research on this. If you’ve experienced what I describe below, please leave a comment.

From what I’ve been able to establish, there seems to be a few things going on that’s causing this to happen:

A Customer Gets Told Their Home Is Not Suitable

Some customers correctly view this as their home not meeting Octopus’ criteria but still consider a heat pump as an option. Others wrongly think their home is now unsuitable for a heat pump altogether, causing potential customers to drop off completely. They are unaware that independent installers don’t have such strict criteria and can make a heat pump work effectively in their home.

Customers Think SMEs Are Exploiting Them

Octopus’ communications around cheap installs don’t inform the customer why they can be cheaper than local installation companies. Octopus has various revenue streams, and sources indicate their heat pump installation business runs at a loss. Local installers don’t have the option of loss leaders to attract customers. This leads to an emerging situation where customers, who initially became aware of heat pumps via Octopus’s marketing but don’t meet their criteria, are reluctant to consider other companies, despite now having an interest in heat pumps.

Even Worse

Some customers try an SME installer after not meeting Octopus’ criteria but view the SMEs as exploitative and charging too much once they see the quote comparing it Octopus’ pricing. This is due to the fact that the customer does not understand why Octopus can charge so little. There’s a risk of installers being viewed as rogue traders, which could spiral out of control and have a massive effect on the uptake of heat pumps.

With thousands of people starting their heat pump journey at the entrance of Octopus’ vast sales funnel, it’s concerning that their interest in low-carbon technology may end abruptly if they encounter obstacles. Proper social science research is needed to understand these dynamics, even if they’re considered big and scary topics. It’s a transition, and there are bound to be significant challenges emerging that shouldn’t be shied away from.

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Toodles
5622 kWhs
25 days ago

My first contact with a company who could install a heat pump for me was with Octopus; they carried out a survey and the subsequent emails that were sent to and received from Octopus established that our situation was not one that could be catered for by Octopus at that time. I did not take this to mean ‘if they can’t then we are not a suitable case for such an installation’. They explained their abilities and the additional conditions that would need to be met and the compromises we would need to make to have such an installation.
We contacted 20 other installation companies and the work for this started straight away as we were determined we still wanted an ASHP installed. So no, we were not put off by Octopuse’s inability to comply with our requirements; they did explain the problems and difficulties involved.
I should add that by the time we contacted Octopus in the first instance, we already had 21 PV panels installed along with battery and had carried out underfloor and loft insulation improvements; the ASHP was just one element in our long term goal. Regards, Toodles.

Mars
Admin
17087 kWhs
Reply to  Toodles
25 days ago

@Toodles did Octopus ever quote you, or was your property deemed not suitable before cost estimates and quotations?

Toodles
5622 kWhs
Reply to  Mars
25 days ago

@Mars We never received a quote; we had numerous emails back and forth discussing aspects of their access due to an acrylic sheet roofed patio that they wanted me to remove before they could commence and erect scaffolding. Lack of space for a DHW tank would have entailed fitting one in the loftspace and they were not carrying out such services at that time; they would also have required a widening of the loft access before they commenced. They required a promise that I would have this work carried out if I had done so, they could provide a quote. Whilst I was mulling over these options, I received another email in which they wished to decline the job as they foresaw too many ifs, buts and whens so to speak. Regards, Toodles.

Rachel Cooper
Rachel Cooper
25 days ago

Octupus are wanting a £500 deposit before they can even give a date for a survey. Which i paid. Only to find out the survey could not be carried out for upto 8 weeks. Not much good to me in the middle of winter when my duel fuel burner with a wrap around boiler sprung a leak. Flooding the room and leaving us with no heating. After paying the £500 deposit I heard nothing from them for over a week then to find out they were still recruiting installers. I desperately needed heating and hot water for my disabled son.
I ended up going with a local installer who did all the home heat loss surveys and every other survey. And had my new Mitsubishi Ecodan fitted all within 2 week. I’ve now had it up and running for over a month and I’m really pleased with it so far. And I’m still waiting to get my £500 deposit back from octupus.

Toodles
5622 kWhs
Reply to  Rachel Cooper
25 days ago

Yours was what is known as a ‘distress purchase’ then? In our case, the gas boiler was some 14 years old and beginning to complain; we had had a new gas regulator fitted by BG under their service contract with us, you probably know the sort of thing where you agree and pay for an annual service that they may of may not get round to doing after 18 months or so, if they have the time!
Anyway, the regulator was replaced after a service that had been carried out caused other things to fail; one of them being that the regulator started to open with a loud roar for a few seconds and this was strong enough to vibrate the whole structure including the wall it was hung on. A year later (I had cancelled the evermore pricey annual service contract by then), the replacement regulator started to fail in the same way. By that time, I was waiting for Octopus to carry out the survey as we had decided to be rid of the gas boiler ASAP. Technically, it was not a ‘distress purchase’ I suppose, but we were very glad to see that boiler lifted off the wall on its’ way to boiler heaven! Regards, Toodles.

Mars
Admin
17087 kWhs
Reply to  Rachel Cooper
25 days ago

Thanks for sharing Rachel, and it’s commendable that you saw it through and persevered making the switch to a heat pump and not taking the easy option of just slapping in another boiler – I hope that your new Ecodan is keeping you warm.

Phobos
Phobos
24 days ago

Its mostly Price .. If Octopus will do it for £0 to £3k + £100/year service perfect , It they say " not yet". & the next best price is £4-£8K + £250/year service, its poor value . ( always ask about servicing) . Even BG aren’t cheap AND they work a " no taking the heat pump through your home" policy. Because Octopus, (did a survey) said " we can’t do that yet " , I am waiting for Cosy6 heat pump.

noburn
451 kWhs
24 days ago

I had a similar experience.  Octopus carried out a survey but decided my installation was not going to be “Standard" and declined to quote. After a lot of research, I contacted a local company who arranged for an independent heat loss survey followed by a quote that I accepted and two months later the installation was fully operational. Although I suspect that if Octopus had quoted it would have been lower, the company I chose had experience of multiple heat pump installations and quickly responded to all the technical questions I raised giving me a “warm" feeling.
To date my ASHP is performing exactly as predicted.

IvanOpinion
322 kWhs
24 days ago

In my case, I would not have started considering a heat pump right now were it not for Octopus quoting a price of £500. I got sucked in by the cheap price and as I learned more I started to appreciate the benefits more. I also came to understand why it might be worth paying more for a different installer, though I have not yet decided.
In my case octopus are £6k cheaper than any other quote. I’m fortunate that I can pay the extra if I wish. Most people can’t.
Octopus seem to be the only one that are aiming at the mass market who won’t buy a heat pump if a gas boiler would be cheaper. I think this is the way to make heat pumps mainstream and make a real impact on carbon emissions.
But they probably are making life harder for other installers, who may be losing work from people who would have paid more if there wasn’t an option so much lower. 

bontwoody
2920 kWhs
Reply to  IvanOpinion
23 days ago

@IvanOpinion Im in the same team as Ivan. I think for all their “picking the lowest hanging fruit", it is the way to get heat pump adoption mainstream.
I also cant help thinking that I installed my heatpump and cylinder for about 5K including paying for a plumber to do the pressurised cylinder install. Thats with no grant so the difference would seem to be an awful lot of labour in some of the quotes that seem common.

TechnoGeek
410 kWhs
15 days ago

Interesting article. I fear though this issue is not just an Octopus one.
I was having a chat with a friend of mine at my local pub and we happened to get onto the subject of heat pumps, which I informed him I had one fitted last year, which he was surprised about.
He informed me that he and his Wife considered getting one but the company / installer at the time told them they needed larger radiators and 22mm piping everywhere. They also where told the system would constantly run 24 / 7 so after that my friend ended his heat pump journey. I questioned the installers knowledge to come up with some of these facts.

After establishing his house was a similar spec to mine, we had the same 15mm piping and radiators together with the fact that my heat pump cycles when necessary and has a set back temp during the night (so not running 24 / 7), his view on heat pumps became a little more positive.

Think a broader social survey would be interesting to see how much the lack of installer knowledge and potential incorrect facts are possibly inhibiting heat pump uptake.

Toodles
5622 kWhs
Reply to  TechnoGeek
15 days ago

@TechnoGeek I fear we do not know how ignorant we are! 😉 Toodles.

JamesPa
4379 kWhs
14 days ago


Now British Gas are saying we need planning permission for a 12kW unit. Nobody can get planning permission in Bristol…

Mitsubishi 11.2kW is within the pd size limits.  Check LG and Panasonic also.
 
Re nobody can get pp, is this for a heat pump or more generally.  You can appeal for non determination if they take more than 8 weeks (unless you give them permission to extend)

Pablito
37 kWhs
Reply to  JamesPa
14 days ago

@JamesPa thanks for the useful information on size limits. Unfortunately I’m limited to what British Gas will offer. 
My comment on planning in Bristol was borne out of frustration. I paid my deposit eight months ago, and British Gas only told me this today. Bristol City Council’s planning department has been put into special measures for failing to respond to applications in a timely manner. I was told today that an application would be three to four months, and I can’t wait that so will be getting quotes for a gas boiler. The sentiment of the original article is what drove me to write. 

IvanOpinion
322 kWhs
14 days ago

After the survey the design team ‘failed’ the application based on heat loss calculations, saying that a 14kW unit would not be sufficient to heat the house. I have had two other companies MCS surveys recommend a 12kW unit.
That’s bizarre, because they currently only supply Daikin Altherma heat pumps and there’s a 16kW model, which is a few hundred quid more than the 14kW model. (Both these models, incidentally, are within the size limits for permitted development.) 
 

Pablito
37 kWhs
Reply to  IvanOpinion
14 days ago

@IvanOpinion In October last year British Gas quoted for a 14kW Daikin, then revised their quote to a 12kW Valiant Arotherm plus in November. Their most recent quote was last week, also the Valiant. Octopus quoted for a 14kW Daikin, but pulled out due to heat loss exceeding the capacity of the unit.

Davesoa
514 kWhs
14 days ago

There is certainly something different about the Octopus process. My Octopus survey, as I’ve mentioned elsewhere, suggested a heat loss of 14300w and therefore a 14w heat pump – which Octopus do not supply. This heat loss calculation is 35% higher than an independent contractor who carried out a survey last year and who recommended a 12w HP.
i got EDF to carry out a survey last week and they calculated a heat loss of 11300w, 17% higher than the independent but 20% lower than Octopus – and recommended a 12w high temperature HP. However the EDF quote is quite a bit higher than Octopus.
I’ve pointed this out to the Octopus team who have agreed to look for errors in their calculations but they will not come back and resurvey. Not sure where this leaves me. I still want a HP but it’s hard to make a decision when there is so much variation in what should be a (more or less) replicable process.
 

JamesPa
4379 kWhs
14 days ago


Not sure where this leaves me. I still want a HP but it’s hard to make a decision when there is so much variation in what should be a (more or less) replicable process.
 

 
Unfortunately sizing heat pumps for a retrofit is very far from a replicable process because the engineer must make assumptions about the fabric which generally cannot be verified.  Infiltration loss (air changes per hour) is, it appears, frequently overestimated but other incorrect assumptions are also possible.   Many installers err towards oversizing because a cold house (due to undersizing) results in call outs, whereas an inefficient heat pump (a likely result of oversizing) doesn’t.
Personally I think that a measured figure should be used to sense check, or even as the primary determinant.  14kW is a big loss (but of course you may have a big/lossy house).  How much energy does your boiler use annually/can you get the usage data/how big what construction/where is your property.
This article talks about the various options for determining the actual heat loss  https://energy-stats.uk/what-size-heat-pump/   If you have any measured data from consumption I would test the spreadsheets against it.
As a point of comparison quotes for my house went as high as 16kW (based on a 3 hr survey).  The measured and verified loss is actually 7.5kW.
 

Davesoa
514 kWhs
14 days ago

@JamesPa That’s a really interesting article. I’m a hostage to fortune with Octopus as computer says No. I don’t believe my house heat loss is as they calculate but their algorithm is not to be argued with it seems even though my gas and electricity consumption (supplied by Octopus) is known. 

JamesPa
4379 kWhs
Reply to  Davesoa
14 days ago


@JamesPa That’s a really interesting article. I’m a hostage to fortune with Octopus as computer says No. I don’t believe my house heat loss is as they calculate but their algorithm is not to be argued with it seems even though my gas and electricity consumption (supplied by Octopus) is known. 

Most mcs contractors I have encountered refuse to take into account measured data, but there are exceptions.  Oversized heat pumps can be inefficient.  If you have measured data I would a) use it if only to sense check and b) persist until you find someone to play ball.  You really don’t want a heat pump that is oversized by a factor of 2 (I’m not saying 12-14kW is oversized, I don’t know because you haven’t posted any info,  but most of the installers I contacted, including two who did 3 hrs surveys, wanted to oversize the pump for my house by a factor of 1,5-2 so I do know that this can happen).
 

Toodles
5622 kWhs
Reply to  JamesPa
14 days ago

@JamesPa And here is an interesting presentation from Heat Geeks on the subject:

Regards, Toodles
 

Davesoa
514 kWhs
Reply to  JamesPa
14 days ago

@JamesPa My actual gas usage is 16500kwh & electricity 3500kwh. My survey assumed a heat demand of 19200kwh. So a heat loss of 14300w? It can’t be. I watched the Heat Geek video mentioned by @Toodles above. Fascinating (and worrying) at the same time. I also visited the Heat Geek site which suggests a heat loss of 8.2kw

JamesPa
4379 kWhs
Reply to  Davesoa
13 days ago


@JamesPa My actual gas usage is 16500kwh & electricity 3500kwh. My survey assumed a heat demand of 19200kwh. So a heat loss of 14300w? It can’t be. I watched the Heat Geek video mentioned by @Toodles above. Fascinating (and worrying) at the same time. I also visited the Heat Geek site which suggests a heat loss of 8.2kw

No your demand cant be 14.3kW.  My annual gas usage is 18-20MWh and my measured consumption 7.5, max 8kW.
Sadly this appears to be ‘situation normal’.  Have you got the spreadsheet calculations from those quoting or is this based solely on eyeballing the house?
The 7kW Vaillant (eg) should do nicely in your case provided you can run (say) at FT45, no pp required assuming you can meet the noise and other misc pd requirements.  11.2kW mitsi is likely overkill, but wouldn’t be a complete disaster because it has a decent turndown capability, the 8.5kW Mitsi is most probably a better choice than the 11.2.  A genuine 14kW pump will be well oversized and qill therefore cycle at quite low temperatures, leading quite probably to an efficiency loss of perhaps 10% (or more if its badly set up).
Have you by any chance got half hourly meter readings to you can prove to yourself and others that 14kW is a load rowlocks?  Probably an irrelevant question because it seems like the industry has effectively turned its back on you.

IvanOpinion
322 kWhs
Reply to  JamesPa
13 days ago

Probably an irrelevant question because it seems like the industry has effectively turned its back on you.
 

I suspect that a Heat Geek firm would not turn their back. They would almost certainly assess a lower heat loss and specify a lower powered ASHP that would meet the noise and size requirements for permitted development. But they will probably charge considerably more than Octopus and BG, which brings us back to the original point about Octopus making everyone else look unacceptably expensive.
 

Davesoa
514 kWhs
Reply to  IvanOpinion
13 days ago

@IvanOpinion and @JamesPa. I do have the half hour readings (but then so do Octopus). However I’m going to have one last go. Today I called a local firm, who have done most of the electrical work in my house and who know the builder and plumbers who built the extension. They have been fitting HPs, they say, for years. I’ve told them of my journey so far, and failure to get anywhere. I have the heat loss calculations for all three previous companies (but not the detailed Octopus results which they will not release). I suspect that you are correct about the original point – they will look expensive compared to Octopus. They, incidentally, fit the Mitsi unit you mention.

JamesPa
4379 kWhs
Reply to  Davesoa
13 days ago

To give yourself more confidence, look back over the past 3 years and work out the rolling average consumption over (eg) 3 hrs, 6hrs and 24hrs, for each half hourly reading.  Then plot the frequency in ‘bands’ on a graph, or look for how often a number above (say) 8.5kW occurs.  If >8.5kW (or some other chosen limit) only occurs after it has been switched off overnight, then you can pretty much disregard it, because its just your heating catching up with a setback and you simply shrink back the setback when operated with an ASHP.
I get (or rather got) a few 9.5kW readings (on a 3 hr average) when I do this, but only in the shoulder season when I had switched off overnight. 
This winter I turned my gas boiler (I too am struggling with PP) down to the lowest it would go (8.5kW), never was I cold and again only in the shoulder season when I had turned off overnight was 8.5kW reached. 
Case proven as far as I am concerned, the 7kW Vaillant (which does 8.5+ at 45C) or the 8.5kW Mitsi will be fine, once I get pp (by fair means or foul) and assuming I can find an installer to play ball!
Another benefit of doing the actual consumption analysis is that it gives you a figure for the typical/mode consumption (probably about half the peak).  Ideally you want your ASHP to turn down at least this far (at the corresponding OAT and flow temp), otherwise it will be cycling most of the time.  In my case its 4kW which is my consumption (+/- 0.5kW) for probably 60% of the season +.  in the cold shoulder this is the 24×7 consumption, in the warm shoulder this is the consumption on the basis that I turn it off overnight so it does some catching up during the day.  Only in the coldest and warmest part of the season does it depart materially from this figure.  So another constraint, for my case, is that the ASHP must turn down to 4kW, preferably a bit less, at 35C flow temp (my design flow is 45) and OAT= (say) 10C.  The Mitsi 8.5kW and Vaillant 7kW both do this, the next sizes up don’t quite and the 16kW that two recommended wouldn’t have come close.
Obviously all this calculation remains theory (but based on experiment), so could yet be proven disastrously wrong.  However that’s still, at least for me, a whole lot more comfortable than overengineering based on guesswork.
Octopus do seem to be doing a good job of keeping prices down but only for the type of install they do.  That’s fair enough really.  The real problem is the price gouging and over-‘engineering’ by the grant harvesters which make up so much of the industry many of whom will doubtless vanish once the grants cease.

GunboatDiplomat
227 kWhs
13 days ago

@Davesoa your gas usage is similar to mine and I have a 130m2 detached property build in 1979. Insulated cavities, 300mm loft insulation and double glazing. I’ve had my heat loss estimated today by a Heat Geek at 8.3kW @ -2.8C with the 7kW Vaillant unit specified so if your property sounds anything like mine 14kW sounds crazy.
I have Octopus coming next week as I’ve been in the survey queue and got lucky with an appointment so it will be interesting to see what they say. I have had some other numbers ranging from 9kW (believable if you assume some of my walls are uninsulated but not backed up by gas usage) to 10.8kW (crazy).
The Heat Geek survey was very close to what I estimated myself and my coldest day assessment.
Obviously doesn’t help with your current struggles if Octopus stick to their guns but hopefully gives you some confidence in your view that something isn’t right with their assessment.

JamesPa
4379 kWhs
Reply to  GunboatDiplomat
13 days ago

I find increasingly staggering that the MCS rules don’t require that the heat loss estimated by GIGO spreadsheet be compared with actual consumption, and that any discrepancy of (say) 30% or more either way be reconciled (with reference to the customer) before proceeding, and the reconcilliation documented.  It’s such a simple check to do yet it’s not required or, by most installers, accepted.  Why?
A cynic might suggest that the regulations protect the installers more than they protect the customer and perhaps this is not surprising because they were designed by the industry.  If the installer follows the rules then they are pretty much bullet proof.  The phrase ‘contractually compliant but unfit for purpose’ comes to mind.
Of course I’m not a cynic so I wouldn’t for a moment make such an allegation.
 

Davesoa
514 kWhs
Reply to  JamesPa
11 days ago

@JamesPa I’ve challenged Octopus’s figures using the very helpful comments from this forum. They’ve come back and admitted that the heat loss might not be correct. However if I’d like to install cavity wall insulation then they will re-look at the heat loss at that point. The EPC confirms that the house does have cavity wall insulation (where it can), the extension built in 2004 was insulated according to building regs at that time and their surveyor was told at the time of the survey. I’ve sent them the certificate of cavity wall insulation (for what it’s worth) but it’s clear they have a process from which they cannot/will not deviate from despite considerable evidence to the contrary.

JamesPa
4379 kWhs
Reply to  Davesoa
11 days ago


@JamesPa I’ve challenged Octopus’s figures using the very helpful comments from this forum. They’ve come back and admitted that the heat loss might not be correct. However if I’d like to install cavity wall insulation then they will re-look at the heat loss at that point. The EPC confirms that the house does have cavity wall insulation (where it can), the extension built in 2004 was insulated according to building regs at that time and their surveyor was told at the time of the survey. I’ve sent them the certificate of cavity wall insulation (for what it’s worth) but it’s clear they have a process from which they cannot/will not deviate from despite considerable evidence to the contrary.

 
At least they admit they may be wrong!  
My understanding is that they are concentrating on a specific subset of properties with a loss of 6 (8?)kW or less.  Probably sensible for them at the current time and, given that this is probably the most likely range, not silly for the planet either given limited resources.
I would like to think that Octopus are doing background work on getting heat loss from half hourly meter data, given that they have tons of such data.  Analysis of the dynamics of consumption against (known) OAT variations and usage patterns which can also be deduced from the data they have is, I feel certain, capable of yielding a much more accurate figure than a spreadsheet ever will.  The spreadsheet will still be necessary to size emitters, but it seems to me that the problem of accurate whole system sizing is well achievable just from the half hourly data.  It should also yield some interesting information about house time constants, which may well help in tweaking a control algorithm.  Of course they don’t actually have IAT, but I would be willing to bet that you don’t actually need that because you have the figures for a range of OATs and so can make pretty good inferences.
My house is also 1930s with modern extensions at various times and several standalone insulation upgrades.  This is just the sort of property where making crude assumptions based on age/whats visible can lead to estimates that are way out. 
 

IvanOpinion
322 kWhs
Reply to  JamesPa
11 days ago

My understanding is that they are concentrating on a specific subset of properties with a loss of 6 (8?)kW or less.  
For my house, Octopus estimate heat loss of 8.8kW and were happy to quote, so I think they probably have a higher limit than you state. But if they aren’t offering a 14kW ASHP then it does seem that they are eschewing houses with highish heat loss.
 

Toodles
5622 kWhs
Reply to  IvanOpinion
11 days ago

@IvanOpinion Or could it be that they are staying below the application for PP level? Regards, Toodles.

IvanOpinion
322 kWhs
Reply to  Toodles
11 days ago


@IvanOpinion Or could it be that they are staying below the application for PP level? Regards, Toodles.
I don’t think so, because Octopus use Daikin and the volume of the ASHP box and the noise level are the same for the 16kW as the 9kW. As I understand it, the 9kW model that Octopus are specifying for me is the same as 16kW model, but with software limiting its output. 
 

Toodles
5622 kWhs
Reply to  IvanOpinion
10 days ago

@IvanOpinion I wonder how well that works when attempting to modulate a 16kW unit down to be a 9kW unit which in turn may be required to modulate down to perhaps 25% power? (I’m assuming that the 16 – 9kW derating is accomplished by modulating – perhaps there is another method to do so?) Regards, Toodles.

Derek M
Editor
13781 kWhs
Reply to  Toodles
10 days ago

@IvanOpinion I wonder how well that works when attempting to modulate a 16kW unit down to be a 9kW unit which in turn may be required to modulate down to perhaps 25% power? (I’m assuming that the 16 – 9kW derating is accomplished by modulating – perhaps there is another method to do so?) Regards, Toodles.

This is a very good question and one I suspect that may be difficult to answer.

One way could be to look closely at the manufacturers data tables (if they are available) for the different models, to see what the minimum output capacity at say a LWT of 35C and an OAT of 12C.

 

IvanOpinion
322 kWhs
Reply to  Toodles
10 days ago


@IvanOpinion I wonder how well that works when attempting to modulate a 16kW unit down to be a 9kW unit which in turn may be required to modulate down to perhaps 25% power? (I’m assuming that the 16 – 9kW derating is accomplished by modulating – perhaps there is another method to do so?) Regards, Toodles.
That’s one of my main objections to Octopus wanting to fit the Daikin 9kW, based on a heat loss figure of 8.8kW, which I’m convinced should be no more than 7kW. 9kW should be fine for mid-winter, as it isn’t too much higher than 7kW. But in spring and autumn, my house will only need 2-3kW and a 16kW machine is not going to modulate down anywhere close to that. 
 

Jancold
571 kWhs
Reply to  IvanOpinion
10 days ago

@IvanOpinion Looking at my Daughters vast Eco Forest 20 Kwh machine it can modulate down to 4 Kwh according to the plate. oops misread 4.2 for 2!.

GunboatDiplomat
227 kWhs
Reply to  IvanOpinion
10 days ago

@IvanOpinion I stumbled across this thread Performance of 9kW Daikin – Hardware / Heatpump – OpenEnergyMonitor Community where at least two people managed to get Octopus to swap their 9kW unit after installation as the performance was dire. I have just realised I will likely get specified the 9kW unit by Octopus as my heat loss is above 8 (though it may be closer to 7.5 if I’m more optimistic about the construction of some walls). Between that thread, not wanting a 16kW software-limited unit and the fact that on paper my airing cupboard is too small for the cylinder (650mm wide x 600,mm deep where Octopus specify min 800×800) I’m not sure even at the cheaper price Octopus will be for me.

IvanOpinion
322 kWhs
Reply to  GunboatDiplomat
9 days ago


@IvanOpinion I stumbled across this thread Performance of 9kW Daikin – Hardware / Heatpump – OpenEnergyMonitor Community where at least two people managed to get Octopus to swap their 9kW unit after installation as the performance was dire. I have just realised I will likely get specified the 9kW unit by Octopus as my heat loss is above 8 (though it may be closer to 7.5 if I’m more optimistic about the construction of some walls). Between that thread, not wanting a 16kW software-limited unit and the fact that on paper my airing cupboard is too small for the cylinder (650mm wide x 600,mm deep where Octopus specify min 800×800) I’m not sure even at the cheaper price Octopus will be for me.
Yes, it is one of those two who first alerted me to the problems with the Daikin 9kW. Octopus have agreed to do a resurvey, so we will see if they reduce the heat loss enough to justify specifying the 8kW unit, which is the top power version of a different Daikin family of models. If not, then, astonishingly, I’m going to be turning down an install that would cost me £500.
 

Davesoa
514 kWhs
Reply to  IvanOpinion
11 days ago

@IvanOpinion Octopus have told me they will have a Cosy 16 next year capable of delivering 50c and will cover the alleged 14kw heat loss – if I’d like to wait that is. Be that as it may if their heat loss is wrong (we know it’s wrong) then it would be oversized by some margin.

Davesoa
514 kWhs
13 days ago


To give yourself more confidence, look back over the past 3 years and work out the rolling average consumption over (eg) 3 hrs, 6hrs and 24hrs, for each half hourly reading.  Then plot the frequency in ‘bands’ on a graph, or look for how often a number above (say) 8.5kW occurs.

@JamesPa – great idea. I’ll download the data. 
@GunboatDiplomat – yes similar house. Mine is detached, 160sqmtr, 300mm plus insulation, double glazed through, cavity wall insulation, south central England. It is a hybrid though and I think that’s throwing the heat loss calculation. Part was built in 1911, part 1970s and part 2000s. I’d be interested to hear the Octopus assessment. 

Majordennisbloodnok
4184 kWhs
11 days ago

As far as I’ve been able to glean, Octopus seem able to offer lower installation costs by adopting a standardised process that can cover the majority of customers and concentrating on the “low hanging fruit”. It’s an eminently rational approach so in theory has my support.
In practice, situations as you have outlined, @Davesoa, show the standardised process Octopus are using still needs a lot of work; there are some significant flaws. Given how well Octopus have treated me as a customer with their energy supplier hat on, I have a fair amount of confidence they will listen to feedback and address those flaws head on. Only time will tell, however, if my confidence is justified.

GunboatDiplomat
227 kWhs
6 days ago

@Davesoa I had my survey – seemed to go OK!
The heat loss came out at 7.5kW which is within my “reasonable" estimates (lower than the Heat Geek one I had done but he assumed some uninsulated walls which I now know are insulated after the use of a drill and an inspection camera!). There was some discussion about the cylinder location – the current cupboard housing it is just big enough for their slimline cylinder, though the buffer will have to go in the loft. The snags are:

Design is for 50C – this means fewer radiator changes but also lower performance. The surveyor was unable (not allowed) to design for 45C.
I have a prerequisite to get some artex removed in the cylinder cupboard as it contains asbestos (fair enough, but annoying)
Their survey software recommends the 9kW unit which I do not want – I need to find the data sheet for the 8kW and see if it can in fact cover my heat loss and argue for this

On the positive the surveyor was open to oversizing radiators they did need to replace (ie a P+ would be fine at 50C but I said can I have a K2 please). I just can’t get all the necessary radiators upsized as some show as no change required with the higher design temperature.
For reference my current fixed quote is ~£5800 which while cheaper than other quotes is not like some cases where it is £500-1000 so I feel justified in being picky at getting the right system as its still a substantial investment. Maybe this will come down after the survey as the surveyor felt it was a pretty straightforward install. For example no plastic in the system, 28mm primary pipework to the cylinder & pump currently, 22mm under the floors feeding the 15mm to the rads and the positioning of the heat pump means a straight via the loft to the current cylinder location (though I think this could go under the floor but they don’t want to lift any flooring..).
Once I’ve got final proposals from the rest of my quotes I’ll lay them out somewhere but thought you might find this interesting. No phantom rooms and the heat loss around where I’d expected.
 

Davesoa
514 kWhs
Reply to  GunboatDiplomat
6 days ago

@GunboatDiplomat That’s good news and a good price as well – I’m only faintly jealous. My indicative quote came out at £6200 (including an unvented hot water tank which I already have so would have reduced the cost) though it’s entirely hypothetical as I still have the sound of silence from Octopus. Organisations do not like admitting errors. I’m still looking for my West Wing of 5 rooms but no sign so far.

Davesoa
514 kWhs
Reply to  Davesoa
5 days ago

A final ‘No’ from Octopus. Apparently they accept that I might have a heat loss of 10w but their software is not able to distinguish the subtleties between mixed construction (solid walls/cavity walls) and therefore they cannot be sure what size HP I might need. I am getting a local installer to come and have a look but, like the OP states at the start of the thread, all other quotes look high compared to Octopus. 

JamesPa
4379 kWhs
Reply to  Davesoa
5 days ago


A final ‘No’ from Octopus. Apparently they accept that I might have a heat loss of 10w but their software is not able to distinguish the subtleties between mixed construction (solid walls/cavity walls) and therefore they cannot be sure what size HP I might need. 

Interesting.  Thats a big limitation on their software/chosen market, they really are going for the low hanging fruit.  I guess they want to get some solid experience and solid numbers from simple properties before tackling more complex ones.  I bet they are harvesting data from the installs and post-install performance to inform their future design process. 
Having said that its actually quite a sensible strategy, albeit frustrating for those of us, like me, with properties that have a mixed construction.
 

Toodles
5622 kWhs
Reply to  JamesPa
5 days ago

@JamesPa And those like me who needed something of a slightly different ‘flavour’ due to space limitations and access. Regards, Toodles.

Davesoa
514 kWhs
Reply to  JamesPa
5 days ago

@JamesPa I agree it’s sensible – now I know what their strategy is and it’s not just a huge error. As I posted earlier they will be offering a much larger HP next year which likely would be acceptable. If I care to wait that long. British Gas are not doing installs in my area so my options are now very limited.

Toodles
5622 kWhs
Reply to  Davesoa
5 days ago

@Davesoa To me, there is something just a little ironic about a purveyor of fossil derived energy promoting and installing renewable energy driven heating systems! 😉 (He-He) [If you can’t beat ‘em..] Regards, Toodles.

GunboatDiplomat
227 kWhs
Reply to  Davesoa
5 days ago

@Davesoa is that a single run of wall in one room is mixed construction? They can definitely deal with different walls being of different construction as I have both solid and cavity walls – unless the octopus surveyor marked everything as cavity and my heat loss is now underestimated!

Davesoa
514 kWhs
Reply to  GunboatDiplomat
5 days ago

@GunboatDiplomat A little more complicated. I have one small room that is entirely solid wall, one large room with one wall run that is about 15% solid wall with the rest of that particular run cavity wall (the other walls are insulated), one room that is a mix, 75% solid (balance insulated to 2004 regs), one room that is 50% solid.

GunboatDiplomat
227 kWhs
Reply to  Davesoa
5 days ago

@Davesoa Ah yeah that is a bit more complex. Though in my mind it’s easy to cater for – calculate the average u-value for the wall and use that. Very frustrating if Octopus won’t allow for that – it’s not hard and it’s the way I had to make things work in the MCS calculator spreadsheet as it has one field for external walls.
 

Toodles
5622 kWhs
Reply to  GunboatDiplomat
5 days ago

@GunboatDiplomat I think some users are wedded to their computers and software, and not allowed to think for themselves – more’s the pity. I spoke to someone a few days back in an attempt to ‘register’ a new freezer. When I eventually got through all the ‘press one for this, press two for this’ nonsense and spoke to the person to carry out the registration, it soon became obvious that it was a data gathering exercise and when asked for my first name, they would not accept just an initial telling me the computer won’t allow them to put in an initial only, to which I told them tough, that’s all I am offering, they persisted, I rang off. Regards, Toodles.

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