GLPinxit

We've just had some minor work done to move a radiator and I was talking to the plumber about bacteria and antifreeze in heat pump systems. He told me about a client who they'd part-installed a system for and who had him back when the whole system ground to a halt some time later. All of the circulating fluid had turned to a gloopy gel and it took several days of continuous power flushing to free it up. He thought that part of the problem might have been that the [clear] plastic drums had sat around in bright sun for some time before their contents were used. I have a particular interest as we are in a sheltered and relatively balmy part of the UK (minus 5 twice this winter) and would like to be able to just have enough anti-freeze to give us protection to minus 5ish. I'll probably add Fernox F7 but am a bit hesitant as we're on private drainage and I don't want to kill all of the helpful bacteria that live in our sewage treatment plant by draining the system down 'our' drains!

I wonder if your Ecodan is appearing to 'not stay on' because the outside air temperature is high enough to mean it cannot modulate its output down to the necessary extent. I get the the same thing with mine at OAT around 14C and am currently puzzling over how to mitigate its impact on energy consumption. Looking at my Melcloud graphs, the system is not so much 'not on' as waiting for the circulating water temperature to cool to the point it 'starts' again. FWIW I am consoling myself that the gently falling temperature graph is an improvement over the frantic cycling of 12 months ago before I reduced the weather compensation curve. And the house feels no less comfortable.

Forgive me if I've misread the first paragraph of your post but you seem to be concerned that you can't heat your hot water at the same time as you heat the house. This is exactly how my Ecodan works and as far as I know everyone else's does too. (And it is a bit annoying on a very cold day when the radiators go cold because the hot water heating has come on.)

What about corrosion inhibitor, I thought that came with glycol? (And I'm currently up-sizing 3 rads in our 8 month old retrofit and that suggests that the installers' flush wasn't fully effective. In our last house I drained the system from time to time as I was making various changes and was used to a clear drain-down as I always put Fernox back in. Here a combination of cost and a sewage digester means I've just drained individual rads as I go.)

From reading this thread it is clear that different installers have different procedures. We got a quote, accepted it, the installer applied for the BUS grant, it was approved in principle, work began. We made deposit and stage payments for the full amount (four in all, before and during the installation with the last paid after it was commissioned and working). Finally, the installer applied for payment of the grant which was made to them and they refunded the £5K to us. The scheme administration seemed to be prompt and efficient and our installer paid us as soon as they received the grant. I can see that this approach isn't perfect and the process design of the scheme administration has plenty of scope for improvement. We did lots of work to find the right installer for us before seeking quotes and being comfortable with the financial side was part of that. In the event only one installer ended up quoting (the lack of professionalism of the others in this also meant we wouldn't have been confident in them).

Having moved house in the last year I have little confidence in the EPC ratings. The assessor for the house I sold was all over the place and I've spent some of the 9 months in the new place finding and fixing a range of draughts- including some monstrous ones. Now, with a newly installed air-source heat pump I've probably made my EPC worse!

https://ercouncil.org/2022/chart-of-the-week-54/ If throwing soup isn't the answer then what else will get the Government to focus? My view, based on having been on the inside of the policy-making prior to retiring recently, is that the difficulty in UK is that the main political parties are in the business of getting elected and don't think people will vote for policies that involve tax being raised to pay for things. (Hence green policies being canned shortly after introduction and potholes all over the roads making life hazardous for cycling.) If we had a proportional electoral system then minority parties could dictate terms for being included in the (inevitable) coalition government that would result. This would have mixed results; eg in Sweden where the very high alcohol duties are the condition demanded by the temperance party for supporting the coalition at the time. Better than global catastrophe, I think. And also likely to moderate policies to be less extreme, generally, to reach negotiated consensus.

I've recently replaced a 20 year old oil boiler with an ASHP (Ecodan 11.2). The oil boiler sounded like a jet taking off, plus pump hum when not firing. The ASHP itself is as close to silent as I can imagine is possible- we were sitting 20 feet from it in the summer and plants waving in its breeze were the only indication it was running. ASHP also has pump hum but no quieter than before (Wilo pumpsj. Note, however, that it was commissioned in August so it hasn't yet run at full chat.

Too right- I've just bought a new air pump for my sewage treatment plant as the old one uses 85 Watts continuously and the new one is just 50 so it will pay for itself in two years.

I've thought about this approach as replacements for the bog-standard extractors in the bathrooms in our otherwise fairly efficient 2004 house so I'm watching with interest. I'm currently deterred by the limited choice to fit the existing holes in the walls and their high unit cost (we would need four). My contribution https://www.vent-axia.com/range/lo-carbon-tempraselv (not seen or tried).

By way of introduction- we recently moved into a detached 2004-built 190 m^2 house in Somerset. It is currently heated by an elderly (alleged 83% efficient) oil-fired boiler nominally rated at 25KW and driving radiators and DHW. One of the early changes we want to make is to install an air-source heat pump (carbon-motivated choice rather than financial). The EPC rating was at D (68) but with our recommended recent changes (low energy lightbulbs) it would now be at C (69). The EPC assessed energy use for the house as heating/hot water 13750/2750 = 16500 kWh/year (this is difficult to validate as we haven't been here long and I'm using the bamboo-cane approach to assessing weekly oil consumption). I'm aiming for an MCS accredited installation but want to be an intelligent client so I'm going to ask some basic questions, here, and hope you lot can help me with the answers. It took us longer than expected to find the house and, while I'm far from knowledgeable, I've been using the time to pick up useful knowledge from this forum and others on BH. I'm a competent DIYer- including designing and installing gas central heating from scratch in a previous house and I'd quite like to do as much as possible myself (eg installing bigger radiators). Which brings me on to today's question: I'd like to manage Mrs glpinxit's expectations as far as possible and she'd like her beloved fridge freezer to be able to stay in the utility room- have I got enough space for this? - once the old boiler goes there will be one consolidated space in the utility room 110cm wide by 235 high and 75 deep- at the moment I'm not clear if we will need to have a buffer, heat exchanger and sundry expansion vessels - on the first floor a vast airing cupboard (with no plans to change it) currently houses the vented hot water cylinder which I anticipate will make way for something more 'suitable' (questions on this may follow) - I need to redo the bathrooms and this is likely to mean I want to move the radiators so I'm working on the basis that the heat-exchanger will make this more straightforward. (Apart from anything else, we're on private drainage so I've no idea what I'd do with a load of antifreeze if I need to drain the system down from time to time.) Questions likely to follow on this too. Thanks, in anticipation, for your time.

I seem to recall an episode of 'Fully Charged' in which they installed a second Tesla Powerwall but had to upgrade to a 3 phase supply first.

I think it depends on how important the 'look' is. We have some Acovas and also traditional cast iron. The Acovas look like mid century continental. Cast iron (depending on detail) looks like more authentic 'old'. The colour is probably the factor that makes the difference (our Acovas came in white and we left them so, cast iron was supplied nude so we had to choose something to fit the rooms and it seemed obvious that white was wrong).

This is worrying to read and I'll need to ponder on it as I'm deciding whether to opt for battery storage, in due course. Or go the EV route (which we will at some point in any event). I'm vaguely aware of one pumped hydro in Wales. All in it makes me wonder if/when the Bristol Channel barrage decision will be revisited.

Thanks, that sounds right up my street. For now I'm waiting for solicitors to get on with it and using the down time to make a 'to do' list- I haven't been able to spend much time at the place but the solid wood front door clearly needs more attention than just a heavy curtain- daylight shows round the edges. I am sure that there will be numerous other areas to attend to and keep me busy.