@julianc

Thanks for responding Julian.  Nice video by the way. A natural thespian.

The main reason I think you went for the Mixergy was due to switchability between PV and ASHP?  If that's the case it won't apply to me as we don't nor I doubt will we have PV.

Hi Mars,

Gardening is fun and easy, 'I let my wife do it'.

@morgan so on the one hand you are correct, the Mixergy works well with our solar PV and diverter. But it worked just as well with my old OSO tank. No, it’s the tech behind the tank that only heats what you need - from the top down, rather than bottom up. This saves energy and is easier for an ASHP to heat the hot water you need. The Mixergy learns your heat demand over time. And as stated on the vid, will stop my lovely wife and daughter keep asking me if there is enough hot water. 😂

So I still think it would be a better solution for your ASHP installation. 

@morgan my Mixergy is at 80.8C, with lowest temp of 18.4C. And I read that from the garden. Easy life

@Morgan, nothing really jumped out looking at your quote, and the pricing generally looks competitive. I see you're going for K2 Stelrads - nice. Are there any really cold rooms where you could consider (and fit) a K3, as they are really quite amazing at chucking out heat.

Hi Julian,

Just a word of caution.

If you live in a hard water area, I remember reading somewhere that temperatures much above 60C can cause limescale formation within your heating system.

It is a good point @derek-m. I’m keen to reduce the temperature anyway (and see if Mrs Julian notices 😜)

@editor

The entire house was cold in winter.  We moved here mid February.  We will discuss radiator options room by room at the next stage.  Nothing is set in stone yet.

@morgan, not surprisingly your quote is very similar to mine apart from the ASHP size and you have one zone to my two.  I don't think the labour charge is too bad actually. We had 4 people for 2 days plus the design work in the background for a similar installation.  I thought the hardware was a lot but it is what it is. My other quotes were about the same or a little more.      

I posted this on another thread - from Alibaba:

11kW ASHP monobloc - $838

Heat pump water cylinder - $286

Radiator-style fan coil unit - $125 (includes 'smart' TRV)

Let's say add 40% for VAT, duty and freight from China (in some kind of volume), so we could roughly translate those dollar prices into pounds 1:1.

How do those prices compare with equivalent pricing from UK suppliers?  I know a few suppliers give list prices on their websites, but I'm curious if anyone knows the equivalent prices an installer would be able to buy them wholesale?

I'm fully aware the quality or performance may well be quite different...

Morning. I’m sure this is a good unit. £600. It’s the equivalent, if you watch Fully Charged on YouTube and the test drive a Chinese EV for <£5000. On a direct like for like comparison, the price is amazing. 50% or more saving. But what about parts, support, maintenance, warranty?  I don’t think an MCS approved installer would fit this?  I could be wrong. Thus you don’t have the heating engineer designed solution for you ASHP. 

@julianc Absolutely, I'm not really suggesting this as a feasible option for a lot of people.  For other thing, the RHI and friends have a list of 'approved' models, and a random import from China isn't on it. And obviously getting hold of support and parts is then your problem as importer. Clearly those things cost, especially when you have an install base of one unit, and the risk of buying a dud might be too high.

But the point is that installing a monobloc ASHP is the same kind of complexity as installing a new oil or gas central heating system (where some rads and piping may be reused). Once demand ramps up, you can amortise support costs over more units and keep parts in stock locally.  And then costs would be broadly in line with gas boiler prices.

Although it's also within scope of someone doing DIY who is willing to take some risks.  If I had a non-critical project (let's say an outbuilding) it's the sort of thing I might consider DIYing.