Ok. This is where I'm at with the tentacled one. BG is next week.

I had a 'pre-installation visit' to check pipe routing before a plan is drawn up and I'm given the full spec heat loss report. The guy knew his stuff and talked it through with me in detail.

I'm the easiest install on the planet - back-to-back pump & tank and no floor board lifting for pipes because I have a spacious stand-up cellar and all pipes are within reach.  

I critiqued the 50º design temp and queried the ancient Type 11 radiators being left in place. 

I also argued that the heat loss survey which uses the same iPad software as Heat Geek etc., is a bit tick box and doesn't consider house orientation, prevailing winds etc and the fact that although it's a bungalow it is built into a hill so one side is not on ground level.

Also, on paper it is a semi but in reality only a small part is connected to the house next door. The houses are offset so there's more external walls. 

So.... with respect to the latter - they add notes which, when it comes to design time, over ride the tick boxes. We'll see.

With respect to the 4kw pump but Type 11 rads and design temp - I'm going to have to argue that one.

I'm not sure 4kw is sufficient but maybe bigger rads will make it work?

The installer, who knows his stuff, agrees with me - K2 rads and lower temp are what I need for more efficient cheaper running costs. Company policy is 50º = less rad changes - which is naughty imo. That's my energy bills... 

He reckoned I could argue for 45º in the spec but no less. But as he said, I can lower it myself by gradual experimentation. But then if I lower it I need bigger 'emitters' no?

I will wait for the spec and see what happens - but basically it looks to me like I need them to either: 

1) fit K2s or 

2) Lower the quote..... A LOT. (I can buy my own rads)

The installers will tweak it to whatever I want and show me how to tweak it further. They also return to run checks and may change rads if it's not doing what it should.

I *may* be able to get the spark to fit a Modbus or whatever for analytics (but that's definitely a favour - not in the spec). 

I was very impressed with the knowledge/experience on show, time taken, the details checked and the listening. So far they deserve their great reputation. 

I'll keep y'all posted on this but please do tell me what you think. 

@lucia I found the octopus survey to be close to my own results - though I did make a point of calling out things like wall construction & window age to ensure I didn't get any dumb assumed values. They did a full floor plan and also were flexible on finding a cylinder that would fit in my airing cupboard (which the standard daikin one did not).

My gripes were the design flow temperature of 50C (which they refused to budge on in my case when I challenged it ), the fact I'd get the 9kW pump for a 7.5kW heat loss (the 9kW is the same physical device as the 16!) and the pushiness of their sales staff. I had multiple calls and texts to commit after the survey reminding me of the looming threat of having a winter installation if I didn't act fast!

@gunboatdiplomat Thanks - that's helpful. Did you go for it? I mean the 9kw? My installer today was really clear about the difference between the 9 & 8kw and he thought the 9kw should be avoided. 

My spec is for a 4kw which is the bottom end of the 8 also clamped down by software. 

@lucia @gunboat totally agree avoid the 9kW at all costs and in proportion the 4kW is the same. Bear in mind that the 4 doesn’t output 4 at -2C so if your heat loss is truly 4kW then you’d need the 6kW. Have you looked at the data sheets? Is your design temperature-2C (benign south) or lower? (heatpunk will tell you from your address then use your judgement on wind exposure which it doesn’t cover).

Roll on the BG visit!

Stelrad have radiator prices on their web site and it’s roughly £150 per one installed. Being cold or over-spent is not a good choice.

it sounds as if you got lucky with your installer for Octopus. But the principle of no radiator changes for 50C flow is just WRONG. But that’s big company rules for you. It’s a good data point though.

Posted by: @judith

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. But the principle of no radiator changes for 50C flow is just WRONG.

Im not sure Octopus is any worse than 'smaller' installers, who frequently insist on radiator (and cylinder) changes even if the customer doesn't want them and understands the consequences.  Nor are they alone in designing for 50/55 and, as the most recent building regs specify a max design temp even for gas systems of 55 (and thus retrofit of an ashp to a property built to regs can be done without any rad upgrades), there is a reasonable argument that this is not a disastrous landing place, provided the customer understands the implications.

My strong view therefore is that all customers should be offered the choice of (say) 55 (with fewer radiator changes, if any) or 45 (with more radiator changes).  They should be told the capital and running cost difference and allowed to choose their own trade off.  Some will prefer to pay a bit more in running cost for a saving in capital cost and less disruption (a factor frequently ignored), others will take the opposite approach.

Larger radiators can always be retrofitted and not everyone has ready capital funds.  There is no reason that the customer should not be king, provided they are given the relevant information to make an informed choice.

@lucia I didn't got for the Octopus route - I wasn't happy with the system design and with it costing £5800 I didn't feel I wanted to compromise on the design. If it had been say £3000 I might well have gone for it even if it was less efficient and the running costs were higher - £2-3000 would buy a lot of electricity!

@jamespa and @judith

On higher design flow temperatures - the Heat Geek installer designed for 45C but did say they would happily consider 50C to reduce radiator changes if that is what I wanted (and either change the design so the Heat Geek guarantee applied to the higher flow temperature and a reduced SCOP, or to kick in once I made my own radiator changes to enable the 45C flow temperature). 

One final point I found amusing: another local firm I contacted designed for 50C and recommended zero radiator upgrades - however Octopus said at least 6 for the same flow temperature. Someone's maths isn't right, especially as the local installer estimated a 9kW heat loss vs Octopus' 7.5kW!

Posted by: @jamespa

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Posted by: @judith

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. But the principle of no radiator changes for 50C flow is just WRONG.

 

My strong view therefore is that all customers should be offered the choice of (say) 55 (with fewer radiator changes, if any) or 45 (with more radiator changes).  They should be told the capital and running cost difference and allowed to choose their own trade off.  Some will prefer to pay a bit more in running cost for a saving in capital cost and less disruption (a factor frequently ignored), others will take the opposite approach.

Larger radiators can always be retrofitted and not everyone has ready capital funds.  There is no reason that the customer should not be king, provided they are given the relevant information to make an informed choice.

I have refused to quote many people as I will not compromise, it is mine, and the technology's reputation at stake.

@gunboatdiplomat The £2-3000.00 extra cost could very easily be eaten up in a few months, Last year I repaired a system with an average winter spend of £2300.00 per month and cold, this year the same property averaged just over £600.00 and was warm, the repair cost £4500.00.

My advice is, do not compromise when it comes to heat pump design and installation, you will be sorry.

Posted by: @heacol

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Posted by: @jamespa

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Posted by: @judith

↑

. But the principle of no radiator changes for 50C flow is just WRONG.

 

My strong view therefore is that all customers should be offered the choice of (say) 55 (with fewer radiator changes, if any) or 45 (with more radiator changes).  They should be told the capital and running cost difference and allowed to choose their own trade off.  Some will prefer to pay a bit more in running cost for a saving in capital cost and less disruption (a factor frequently ignored), others will take the opposite approach.

Larger radiators can always be retrofitted and not everyone has ready capital funds.  There is no reason that the customer should not be king, provided they are given the relevant information to make an informed choice.

I am not sure you realise the implication of design compromise. It can quite easily double your current heating bill, 

I have refused to quote many people as I will not compromise, it is mine, and the technology's reputation at stake.

 

I know what the manufacturers figures say!

Taking a concrete example, Vaillant 7kW scop is quoted as 3.91 at 45 and 3.39 at 55.  That's no where like double.Are you saying that the manufacturer data is so far out that we might as well ignore it, or are you exaggerating/being purist.  Is your comparison for the same house and otherwise the same design?

For the the avoidance of doubt, I readily accept that badly designed systems are almost certain to be expensive to run, and lower flow temp is better, but, unless the manufacturers figures are nonsense the effect of this variable alone is nothing like what you are claiming.

Some people simply don't have the luxury of indefinite capital funds and are forced daily to sacrifice 'running cost' to save on capital that they simply don't have.  That's why people rent, get a mortgage, put off doing insulation, take out loans and why there may well be a market for 'rented' heat pumps.  So long as they are clear on the tradeoffs you would surely agree it's their choice not yours.  Of course it's equally your choice whether to quote or not.

Once again I stress I am not advocating bad design.  The best design of all takes into account both customer needs and the technical requirements.

@heacol £2300/month? Yikes, that is shocking example.

My comment on £2-3000 buying a lot of electricity really should have been caveated on the system being well designed. The proposed SCOP from octopus was 3.6 @ 50C, the proposed minimum SCOP from heat geek was 3.8 @ 45C. The running cost difference I calculate is about £90 a year assuming those could be achieved. Obviously if they couldn't be achieved (and I had serious doubts on the 9kW Daikin octopus proposed) that capital saving could be quickly eaten up.

@JamesPa

They should be told the capital and running cost difference and allowed to choose their own trade off.  Some will prefer to pay a bit more in running cost for a saving in capital cost and less disruption (a factor frequently ignored), others will take the opposite approach.

I see your point and agree to a degree but the point here is:

a) I'm not being given that choice and

b) the capital cost is the fixed/same whatever you have with Octopus.

They offer instant online 'fixed quotes' based on a couple of very generic tick boxes before anyone has seen your house or had any details. It's literally, house or bungalow, semi or detached, number of bedrooms.

Everything, no matter what size heat pump or water tank, including all the radiators, is included in that non-negotiable quote.

My lead installer, who really knows his stuff but has no impact on the quote which is strictly sales (who know zilch) agrees with my perception. He suggested I try to fight my quarter. But he warned me they won't drop below 45º and they've only done that for a few people. I don't see why I should pay extra for radiators that are claimed to be part of the quote. I'm not sure the heat pump is big enough either. (Ironically, considering how I started this thread.) 

So....

*First annoyance: I'm being quoted many thousands of pounds more than others (I've now found videos of 3 Octopus installs identical to mine but with multiple rad upgrades, who have posted images of the quotes and spec) for a lot less. 

*Second annoyance: The 50º is to save Octopus money nothing else (I was told this by Octopus staff). It means fewer or no rad changes. But I pay for this in higher energy bills further down the line. That's wrong.

It's great that those with money can play the solar/battery game but most people can't afford this. They're at the mercy of energy prices artificially inflated by speculators, geopolitics and dumb energy policies. 

Thus unless electricity prices are delinked from gas and unbundled from the SC add-ons, there's going to be a lot of annoyed joe-public consumers who will feel conned by the energy bills they get from their 50º design temps. 

*Third annoyance: The lead installer agrees that I'm the easiest install ever. An easy access, cavity-wall insulated cellar for the water tank to sit back-to-back to the pump and ALL electrics and pipework for heating and water visible and accessible at just above eye level. Not one single floor board to come up, no channeling wiring, nada. 

The problem with heat pump installation costs and their perception is that installation prices have been absurdly inflated. Not by any stretch of the imagination are the costs including labour, design time, kit etc., relevant to the realities of what a lot of people are paying.

Octopus have scale on their side in terms of kit costs, they pay lower wages (but staff I've spoken to accept this in exchange for good work/life balance, high quality training). Octopus' business model is about brand and capturing markets - their serious money comes from Kraken. 

I'm so low-waged atm I actually qualify for ECO-flex but I can't get a fitter and most of them are so dire I'm not sure I want one anyway. I'm prepared to fund an install but not at Heat Geek rates. And I certainly can't afford to pay for radiator upgrades further down the line.   If I can't get this right in terms of cost/efficiency I have to buy a new gas boiler. All things considered, that's absurd. 

I'm looking forward to the BG survey because the comparison, which will note but not include rads, will be interesting. 

@gunboatdiplomat  

My gripes were the design flow temperature of 50C (which they refused to budge on in my case when I challenged it ), the fact I'd get the 9kW pump for a 7.5kW heat loss (the 9kW is the same physical device as the 16!)

It sounds like we are in a similar space - your quote was a lot higher than most, so is mine.

You were designed for the 9kw which is in reality the software limited, bottom rung of the 16kw - I've been offered the 4kw which is the software limited, bottom rung of the 8kw - neither have the modulation range. 

I'm also not happy with the 50º design temp. 

My spec isn't nailed down yet. I was lucky with my lead installer visit because the guy knows his stuff and is really passionate about it. So I'm hoping that when the official spec arrives I can go for a negotiation. But it's battling with the dreaded 'head office' syndrome. 🤦🏻‍♀️

The crazy thing is that half my village is watching and waiting for me to give them a verdict for their own decisions.