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Cool Energy CEiVt9 ASHP - DIY install
Just ordered my Cool Energy CEiVt9 - DIY install, with a 150ltr slimline heat pump cylinder that I found cheap on eBay and no buffer or llh. Will see how it works out 😉
3 bed end of Terrace in rural Somerset, heatloss calcs using the freedom toolkit came in at 6.7kW. New rads throughout on a manifold, single zone, trvs as hi-limit stats upstairs only. Ufh in the new build extension we’re working on.
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.
I'm always intrigued by projects like yours @hughf. Did you also get the Cool Energy CEiVt9 online?
Please post photos and updates here. I'm really interested to see how it turns out.
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Posted by: @editorI'm always intrigued by projects like yours @hughf. Did you also get the Cool Energy CEiVt9 online?
Please post photos and updates here. I'm really interested to see how it turns out.
It’s a work in progress Mars. We’ve decided to do one more heating season with our gas boiler and put in a new heating system next spring when we start on our extension. We’re about a year behind schedule. I’m slowly collecting parts as I find them though.
I’m not doing it on a shoestring budget, but I also object to paying crazy rates for commercial installers to do what I’m perfectly capable of doing myself, hence my diy mix and match setup.
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.
This is the current plan. UFH in the extension, close coupled Ts on the return line giving the hydraulic separation for the ufh circuit. Manifold plumbing for the rads (I have the manifolds already), the whole lot as one zone. TRVs acting as hi-limit stats on the upstairs bedroom rads only. I might need an adjustable bypass on the end of the rad manifold, not sure yet.
I’m hoping I can get the weather comp curve set just right so that I can do away with a house stat altogether, just program a nighttime set-back on the weather comp curve. We’ll see how that works out.
If we do end up with a room stat, it will probably be something with a hi and lo limit stop. Min 17, max 21
Heatloss calcs using the freedom spreadsheet comes in at 6.7kW when it’s -3 outside and 21 inside.
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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