Can I Install My Own ASHP?
It seems like a simple question, but I'm struggling to find an answer.
For background, I've had some ludicrous quotes to supply & fit an ASHP. Last year I had an estimate at ~£11k - so I assumed that now, minus the BUS payment, it'd be a no-brainer to get one.. but the cost seem to have increased to ~£17k now. This is well beyond what I'd be prepared to lay out.
As an alternative, I'm exploring sourcing & fitting my own system. Can anyone explain what I can, and can't do myself?
Thanks guys 🙂
I think there's a PP subtlety - if an ashp is installed by an mcs installer, then it is PD (permitted Development). If it's diy, technically PP is needed, I suspect a lot of people don't bother. I expect what planners (should) care most about is noise nuisance, so how close it is to next doors windows etc. How well do you get on with your neighbours?
Pick a monoblock unit - you're definitely not allowed to do anything with the F-gasses that most units have inside them (so any kind of split units with F-gasses (most of them) need an F-gas fitter). A monobloc does not need F-gas cert to fit.
Actual install is plumbing and electrical work. I think it should be plumbed into it's own fuse in a consumer unit, and your not allowed to do that bit.
So I think if diy and you get PP and a monobloc and get a electrician to wire an extra fuse in to an isolation switch in the right place you are allowed to do everything else. Disclaimer disclaimer - I'm just a diy-er, I can be wrong !
Posted by: @roblI think there's a PP subtlety - if an ashp is installed by an mcs installer, then it is PD (permitted Development). If it's diy, technically PP is needed, I suspect a lot of people don't bother. I expect what planners (should) care most about is noise nuisance, so how close it is to next doors windows etc. How well do you get on with your neighbours?
Pick a monoblock unit - you're definitely not allowed to do anything with the F-gasses that most units have inside them (so any kind of split units with F-gasses (most of them) need an F-gas fitter). A monobloc does not need F-gas cert to fit.
Actual install is plumbing and electrical work. I think it should be plumbed into it's own fuse in a consumer unit, and your not allowed to do that bit.
So I think if diy and you get PP and a monobloc and get a electrician to wire an extra fuse in to an isolation switch in the right place you are allowed to do everything else. Disclaimer disclaimer - I'm just a diy-er, I can be wrong !
Thanks @robl, I'll take a look into the planning permission to see what I can surface up.
Posted by: @cycleneilHave a look on the ASHP section on the buildhub.org.uk forum, there are quite a few diy installers on there.
I had signed up for an account there, and asked the same question. For anyone else interested, here's the post.
Yes you can do DIY, I did it fine and enjoy telling people my ASHP cost less than £3k.
As above, only consider mono blocks, which are basically fridges with a few more connections.
Before buying, read the instructions to be understand what is required. I cannot find the one I bought on the Internet now but if I was doing it again I'd consider this one on ebay:
https://www.ebay.co.uk/itm/294976537495?hash=item44adf8c397:g:GYoAAOSw8e9icofo
As there appear to be instructions here:
Good Luck and I'd be interested to hear how you get on. My set up is described here:
https://renewableheatinghub.co.uk/diy-air-source-heat-pump
Jon
@teagate, welcome to the forums. Outrageous that the quote got inflated on the back of the BUS grant, but sadly this is what’s happening.
If you have plumbing knowledge and know how, and the ability to do it, DIYing a heat pump is definitely very possible. The major heat pump manufacturers provide detailed documents on how to install and connect everything. The savings would be immense.
What would be worth checking is manufacturer warranty, but I suppose your install would be no different to a non-MCS accredited installer.
Jon is a great example of a DIY install. Here’s Jon’s DIY install article: https://renewableheatinghub.co.uk/diy-air-source-heat-pump
Let us know what you decide and if you pull the trigger.
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DIY installation of a monoblock really couldn't be simpler - 28mm to a 3 port diverter, one side to your heating, the other to your cylinder coil or sunamp. If you've got a mixture of rads and ufh then you'll want a buffer or LLH on the CH side to take care of the different flow rates.
Setup the weather comp on the supplied controller and wire it up to a suitable breaker. It's really much, much simpler than a gas boiler.
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
Posted by: @hughfDIY installation of a monoblock really couldn't be simpler - 28mm to a 3 port diverter, one side to your heating, the other to your cylinder coil or sunamp. If you've got a mixture of rads and ufh then you'll want a buffer or LLH on the CH side to take care of the different flow rates.
Setup the weather comp on the supplied controller and wire it up to a suitable breaker. It's really much, much simpler than a gas boiler.
Since it is so simple, why do many MCS accredited installers make such a hash of it?
@derek-m Because they don't actually understand the science behind how these things work and try and set them up like a boiler. They expect the manufacturers installation courses to make them an expert, that simply ain't going to happen.
If MCS is a pay-to-join accreditation scheme (I haven't actually bothered to check if it is), like FENSA (Don't get me started on the standards in the window installation industry), then it isn't even a proper quality standard, it's merely a money grab.
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
Posted by: @derek-mBut it is keeping loads of people employed using tax payers money, or do they add it to the electricity tariff?
Sorry, not quite sure what you mean by this question? Is it relating to where the funds come from to operate the MCS scheme?
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
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