We’ve been researching them…i don’t think the noise would put us off… but like most things I suspect they get noisier as they get older.
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Jim - Has that ASHP got enough of a gap at the back and the side?
I have decided to give the ASHP a miss for a few years.
The issue for me is noise. The only place where it would produce an amount of noise that would not be an actionable issue for a neighbour would be right underneath my bedroom - so I’d get the noise! That’s not acceptable. It’s also a bad place from an installation perspective, being in an intrusive place in the garden and would need long pipes.
I imagine that I could get around this problem by simply getting a much larger unit. While in principle these make more noise (the larger ones have two fans), in practice it would be running at a lower fan speed most of the time.
It’s a bit like computer CPU coolers - I would always get the massive ones with heat pipes and really slow fans (or no fan at all). However, spending four times the price is easy to justify when it’s still only £30, less so when it’s thousands!
So I’m going to wait until the market is more mature, and there are more units available that are designed for higher density housing like my Victorian terrace.
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Do you mean the big Mitsubishi Tristan? That was already here when we bought the place. I can only assume it was installed correctly by professionals… 
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Yeah I looked into that, but couldn’t find enough out about actual levels of noise reduction and any reduction in efficiency.
The whole thing just became too annoying to bother with!
I work with these things, not directly but rather as a gardener, they’re part of what I have to design around. They’re a bloody menace in a small space. Yes, they are fairly quiet if you’re deaf, and in case you aren’t, the boxes that make them ‘quieter’ are enormous and restrict access for servicing, so need a lot more space than you might imagine. And they don’t make much difference.
New ones are a bit better to be fair but I can’t get round the staggering inefficiency of GSHP which should be much better (in winter and on paper).
Just buy a house with a lake, pop in a heat exchanger and presto, the problem is solved 
Really??
That is not my experience of them at all.
What figures can you back this up with ?
My energy bills say otherwise, and our pump is quieter standing by it than next door’s kitchen fan at the same place.
Our newly built offices are heated with an ASHP, yes the building is well insulated but it is very efficient system. Part of the problem is installers are fitting them to properties with inadequate insulation where they will never work well.
The company I work for has done a lot of development work with Octopus to make the housing for these, companies are looking to improve the look and make the look less like a white box.
Still learning how to use the site, ignore
This trying to reply to Stepmotheratomic. My evidence is anecdotal, like yours. Two clients had them installed, extensively at around 1m depth, pipes spaced at about 2m (IIRC), one was over about a hectare, the other maybe half an acre. The first, after a couple of years turned it off, said it cost too much to run and he regretted ever installing it. The other limps on with his and complains to anyone who will listen. Yes it saves him small coin on his energy bill, but will never begin to pay off the capital cost of installation. Bear in mind these people are bottom line driven money men with large properties and professional installers. They don’t care about the planet, sadly.
Two current clients have large estates and both have used energy consultants to look into GSHP, then scrutinised their offerings with due diligence. They aren’t biting, saying that the return is marginal and not worth any upheaval. ASHP are a non-starter for them due to historic parks and buildings listing, &c.
I live in a village they are trying to run on GSHP, but ground temp was a bit low, and couldn’t get enough density, because of heat loss.
It now has it’s own solar farm, two gigantic ASHPs, and four large storage tanks, for hot water, to supplement the GSHP.
It has reportedly cost at least 23 million pounds, to date, and they only have seventy houses connected, so more expenditure to come.
It can never pay for itself, but we will be off oil!!!
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This for Mr Kettle.
Talking about things not making much difference, I was referring to the enclosures that make ASHPs quieter, not.the ASHP itself. Those enclosures make little difference apart from real estate IME.
Agreed, some ASHP for smaller residential installations are pretty quiet, I wasn’t talking about them because I have no knowledge of their efficiency but, as in my above post, several clients have them. They don’t complain so I presume that they work. I complain about them if they’re in my gardens, but that’s different. It’s because they’re ugly and difficult to hide. Especially if in a huge louvred box with doors opening left and right, and standing space required to haul the units in and out for maintenance which seems to be impossible to carry out inside the ‘sound proofed’ cabinets.
Mine is not anecdotal I have installed and managed a few gshp installations and the owners have been more than pleased with the results. The first one I put in is over 10 years old and the owner is still raving about it. Most often I find with this kind evidence its usually bad design
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Undoubtedly it is bad design. If they didn’t work at least in principle nobody would bother installing them. I suspect inadequate site (and especially soil) investigation but who knows? What is for certain is that realistic assessments of volumetric heat capacity and thermal conductivity in a given soil won’t be in anyone’s crib sheet so needs evaluation. Either way, my clients’ GSHP systems were installed by persons calling themselves professionals in the field which, since the end result didn’t pan out, means they were a combination of either chancers, lazy mined types, or unlucky. Your clients can be grateful they got you.
Unfortunately I come across this a fair bit. The worst one was a block of 91 flats. 5 years down the line the two gshps have never been switched on as they will just not work ,quite a few reasons why but fundamentally terrible design . These were 2 commercial gshps . The best we could do ( we came in after it was £1.6m over budget) was design a hybrid system that potentially could start the gshps in the summer months…that phase is still ongoing .
Unfortunately the client had their hands burnt and has now halted all heat pump installations and is installing electric rads everywhere
Anyone gone for an Octopus Cosy 6 heat pump?
We’re interested in this.
Have underfloor heating so ideal.
Cost would be £500 all in! They say.
That includes a new hot water cylinder.
We can have the pump upto 12m away from the HW cyl.
So can be on the side property out of the way.
Basically it’s £8000 minus Gov subsidy of £7500.
The Cosy 6 is said to be 4 times as efficient as Gas B.
Due to underfloor heating factor we could save a little bit maybe…
It’s attractive, as boiler is 10 years old and would cost £3K+ alone to replace.
Hot water cyl is just out of warranty too.
Also get system drained and new inhibitor etc for free.
Heat pumps are reported to last ~2 times longer than gas boilers and require less servicing costs.
We currently have 6 thermostat zones for the underfloor heating.
The Cosy 6 system allows for 4 control pods (need to find out more about them).
I guess one pod for the downstairs zone, one for upstairs, one for HW cyl? One for music loft radiator?
The latter would be replaced if necessary, included in the price!
The 6 Polypipe thermostats are all 10 years old too.
Cost £75 each to replace… something to consider.
It’s possible to balance the room zones by adjusting the manifold flow to get each floor even.
Would lose the ability to have a cold bedroom, but we don’t do that anyway…
The pods are controlled via the Octopus app.
So can pre warm the music loft from lounge armchair👍
We are also thinking about the Octopus solar installation, have suitable outbuilding at rear of property so no panels on front elevation👍
Electric car probably not very far off too…
Interesting times.
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Our air-water-underfloor heat pump system is quite energy hungry and expensive to run (see upthread).
We have a big solar/battery system to offset that cost.
Also lecky is three times the price of gas. So think carefully and do the maths.
That’s interesting.
Currently including current cold snap we have, the heating is on downstairs for less than 1 hour in the morning.
Water is at 45 or 50 degrees, can’t remember.
The thermostats click out at 19°C, but the floor keeps giving and the temperature rises to 21.5 pretty soon.
We don’t have the heating on for the rest of the day.
It’s still 21.2 in the lounge now.
House is thermally efficient.
Upstairs it’s basically never on.
Our gas usage for heating and hot water and range hob is 9000KWH per year.
If the Cosy 6 ASHP is 3 to 4 times more efficient, elec 3 times the price…
Still, the Devil is no doubt in the installation.
It’s the all new appliances for £500 that got me interested.