MikeSharp01

Clicky pipes, when pipes expand and contract, have until today been quite a comfort. You know things are happening - the central heating comes on the pipes click, it goes off they click, click, click again, you dump a whole heap of hot water down the kitchen sink and click click click. So it goes on. Last night we stayed in a hotel and everytime anybody did anything, our room or others, the pipes went clickety click - and it finally got to me. So, although we have done first fix plumbing, I am going to work out how to prevent the clicking and rework it all. The problem is I don't have a clue how best to do it. I assume the clicking arises from / at the pipe clips - where else can it be. How have other people overcome this or am I really over thinking this?

Sort of agree but I guess it depends how smart your controls are, it was only an idea and it would need to account for consequence loops if implemented and if it went into defrost while heating the DHW alone the risk you mention is still there so switching the UFH into the circuit perhaps on its own at that point could mitigate the risk although then you would be drawing a small quantity of high temp water into the UFH which might not be healthy. PS all this on the assumption the HP does not reverse the flow in defrost if it does then that might be a complication. Just run the immersion off the battery to make up the loss.

Sounds topologically like Y plan then. We won't have the two wired together as I am thinking to switch both the to open position if the ASHP goes into defrost so as to max out the heat available although we have around 50l in the UFH and if that is at 20⁰ there should be enough heat, it weighs 44T, in there, even if it goes round a couple of times, to defrost the heat pump, if not bring the DHW tank pipework into play.

I just thought I would ask MS Copilot to give me an overview of the sizing views here. Worked out OKish and this thread featured. Prompt was simply: "Hi, what is the consensus on buildhub.org.uk about sizing a heat pump to a house please." (I always include the Hi at the start and the please somewhere because I don't want to degrade my attention to such things in other parts of my life - IE I want to avoid assuming that everybody I talk to are automata.) Result was simply: " On BuildHub.org.uk, there's a general consensus that accurate heat loss calculations are crucial for sizing a heat pump - https://forum.buildhub.org.uk/topic/42699-heat-pump-sizing-sense-check/. Users emphasize the importance of considering ventilation losses, insulation quality, and the specific heating needs of different rooms - https://forum.buildhub.org.uk/topic/42699-heat-pump-sizing-sense-check/. Many contributors suggest that over-sizing a heat pump can lead to inefficiency and reduced lifespan, while under-sizing can result in inadequate heating. It's recommended to size the heat pump to handle 99% of the heating load, ensuring it can cope with the coldest days." So this thread features as do others. EG this one:

So all you need to do is reduce down to 6mm at the very end, making sure the cable is clipped direct - ref method C. While scrubbing the 2.5mm spur and going another way with that. Alternatively you could discuss the definition of "dedicated" and spur the 25mm at the very end of the cable at the EV charger. I am dedicated, and vice-versa I hope, to my wife but we also have two kids🤔 to whome we are both dedicated.

Won't you need to split and re-fuse the 2.5mm line - switch fused spur in a weather proof box. Otherwise you could draw 40A through the 2.5mm cable which could turn out to be a very bad idea.

Makes perfect sense. I think provided I make it properly, no corners cut, use common building blocks, document it to within an inch of its life and don't demand any cloud connectivity I hope to be OK. I will also take our kids through it so they can help their mum if needs be. There should be room in the panels (2×600×700) to go proprietary if needed.

It's a Brother E560BT, I think there are other versions that take the heat shrink as well. I got mine from Screwfix for £145. https://www.screwfix.com/p/brother-pte560btvp-electricians-label-printer/739ta

Don't get me wrong - I acknowledge the issue. I have been documenting everything, all the wiring, all the plumbing, the MVHR, I even have a load of the ASHP documentation done, even though I haven't chosen one. I know enough about what will turn up to get cables, pipes etc in place and today I got so frustrated with manually labelling everything I went out and purchased a label printer, fun tool very useful for making sure everything is documented, everywhere! (Love the way it prints heat shrink labels.

I guess it's because I can and I do understand the issue. There are dimensions to the thinking here which we probably need to face head on. Our homes are getting ever more sophisticated and we already rely on technology that is hard for the average tradesperson to keep track of - look at all the discussion here about how well ASHP technology is understood. This does not mean that tradespeople won't get more capable over time as younger people with more digital depth get a foothold and we can also think out of the box to find people who can look after it. Once you have Solar, a battery or two, diverters, energy management and an EV you have a set of very sophisticated possibilities and needs if something goes wrong. I will do everything I can to make it possible to revert, hence being able to switch out the DMX controller, which is a very well understood technology in stage, set and party lighting - we have a big creative industries sector using this gear all the time, using standard switch units in normal places around the house and having full documentation of the system in the form of an M, E & S manual. Using very common systems, such as RPi, MQTT, ESPHome and Home Assistant, also helps bring it closer to serviceability. Finally and I suppose something of a cruncher for me, given we have such sophisticated gear in our homes we will be looking down replacement of the various systems over time anyway and provided we have good infrastructure that is well understood later users can migrate in their own directions.

Read a lot about DIM16-ACL, here and elsewhere, and it is time I purchased one to control the lights (well some of them we need to dim) in our build. I am thinking of controlling it using an RPi PICO, perhaps running ESPhome, via an RS485 bus driver interface using MQTT for full control and direct inputs to the PICO from the momentary wall switches (with suitable opto isolation) for very low latency simple On/Off. The house will have Home Assistant running on RPi 5, with a cloud based private MQTT broker (using Transport Layer Security (TLS) and End to End (E2E) protocols if possible) so I can get in and out via MQTT from anywhere securely. Not sure if that all makes sense but it feels like a workable solution, and if anything fails I can bridge out the DMX controller and connect the lamps to the switches. So in normal circumstances HA will control the brightness using occupation sensors via MQTT (or otherwise directly using ESPhome protocols), switches will be used for legacy reasons and a mood lighting app (TBA). What is anybody else doing with it. I know about @Thorfun system using LOXONE but I want to go somewhat my own way on this so trawling for experience from the wise crowd. Any thoughts welcome at the party.

22p but I guess the problem is the ASHP COP I could not see how to set that. Pin was in Whitstable - where the house is.

Interesting read, makes you wonder why they don't all have the Viessmann feature. What I don't want is an litre tank emitting heat all the time outside the heating periods in the year so having that extra bit of volume only when you need it makes sense. I suppose you could implement it yourself, assuming you feel you need it - system volume wise, if you knew that a defrost was coming or perhaps by running both the UFH and the DHW circuits together when the defrost was on to maximise the systems volume.

Just had a play with it for our build. It is within phpp ball park on heat losses but massively over on cost, seems odd.

Cripes is it nine years already?

That is what I thought but zooming in you can see that it is not - looks like either nutserts, see below, or a bolt with the head on the wall side of the board, which is why I asked.

What a great video, watched couple of others and wonder how secure our locks really are? Eeeeek

Looking good, how are the pipe stands from the top tundish fixed to the ply wall?

I did it as well.

Don't worry the Chinese have done AI with a fraction, allegedly, of the energy needed by the US systems so we can look forward to fewer emissions coming our way from China perhaps.

We have zender ones fully adjustable flow and don't need any fixing they grip the plenum pipe. https://www.international.zehnder-systems.com/en/comfortable-indoor-ventilation/products/air-diffusers

I believe you can, I am sure I saw it done on one of the TV build programmes (Grand Designs or Building the Dream) but it won't be cheap.

Yes that's because Google is bigger than any spell check and it knows how the planets dyslexic people ask questions and what they really mean, really.

Dyslexic and spell check are good friends sometimes Yes - don't I know it. Took me 5 goes to get my English O level.

Payback time can be worked out in a variety of ways. Try net present value and see how it comes out or real rate of return is another option.