MikeSharp01

Hi Bob and welcome to THE forum for people like us.

I wondered about that but I think I can fit the extra one to the current setup and fit gauges on the input and output pipework

So in a no mixing ASHP install that I am putting together the flow does go in the top and out the bottom which makes perfect heat flow sense to me? This how it is set up here based on the manufacturers details, but I feel the air trap and pressure gauge are mixed up surely any air will get pushed to the outlet and you might want to know what the input pressure is - although not sure it matters.

Just poking this thread as it came up in a GPT chat today as a reference. I think the flow and returns are mixed up here. Should the flow go in at the top and out at the bottom - well at least that is how the arrows point on ours and judging by the annotated photo same as for the OP. I guess my question is does it matter given the image above does it the other way around. I would have thought the flow meters would be single direction or is the image wrong?

We have done this and I have found that it works but only up to a limit - once temps are at 30+ it is not able to make things comfortable, so after this summer I am fitting fan coil units in the bedrooms so I can cool them if I need to.

Shame I bought two of these 3 months back ready for the roofer to fit!!!!

Those cable sizes seem very large are you calculating it, if so how, or using some sort of lookup table?

They do have CIL in Canterbury so do that before you start any building work of any sort.

Yes I think I hope they get to keep it, such drive - the site manager was the best bit, ground worker to project managing a 7m build over night.

Watch today's Grand designs - 2000 sq M 7+ million and we are not at the end of the program yet. It will make your eyes water....

Us too - no issues, quality gear I think.

Your pic shows a rather poor connection between the pipes and the floor above, at least in the bits we can see - air is a reasonable insulator so as things stand you are not getting the heat from the pipe into the floor very well, can you still access it or are you beyond that stage already? Going forward there are perhaps two approaches. Try to stop all flow in the downstairs and then experiment with the upstairs manifold flow rates and the water temperature (+delta T) to see if the upstairs system can be adjusted to cope without the downstairs in circuit. (Keep notes of the present settings so you can return to them at any point.) If it can't then you may need to fall back on making the downstairs do all the work. Do the heat calcs - how much heat you need out of each zone for the length & diameter of pipe, coupling losses, area of the zone etc. Then adjust the flow rate settings in the controller for each zone and see what happens. I get the sense from your original post that the bathroom is your principle concern so maybe just run / play with that loop. Get a gun type thermometer to measure the temperatures everywhere (pipes, floors etc).

Finding pressure drops for components in heating systems can be a pain and while I was looking to do a more detailed analysis of our system prior to install I came across this paper from 2019 that gets well into the weeds of the pex-al-pex pipe and fittings. Well worth a look if you want to understand the details and see the difference a coupler, a union and direct connection. Link is: https://www.e3s-conferences.org/articles/e3sconf/pdf/2019/26/e3sconf_eko-dok2019_00045.pdf

I suspect we need a bit form information / knowledge to help reliably: Is it all coming from 1 manifold or more than 1 (how many)? Do you have multiple pumps in the system or just one? What is controlling the flows is it individual loop actuators or some other?

You will find exporting excess PV difficult if it is not an MCS certified install.

@JamesP & @nod thanks both.

I am just putting the ceilings up where we are using resilient bars and wondered what the best approach would be A or B below. The joints will be tapped but in A are you likely to get movement between the boards? In B you have only a very narrow space to place the screws.

Post a picture or two so we can get an idea what they might be.

Yes I think there is, I am 'in negotiation' now. 22% is a good compromise perhaps and -10 is plenty down here. I think I need to look at the delta T because that has a big effect on the head loss, I just need to keep the interface (between the screed and the wooden floor) temperature below 25 degrees C to meet the guarantee on the floor so its not going to be big if I want 21 deg C room temperature is it.

Many architects and independents offer this service. I chose to take the course, buy the software (excel spreadsheet really) and do it myself, seems to have worked out OK for us.

Coolenergy CE iH6+ and Thermox DTX. My problem is our longest loop at 185m of pipe over 40m2 of floor. I put it in when I expected a solid polished floor and thought the 1.5m head loss would not be a problem but now we are going for a wood floor with a TOG of 1.5 so the picture is very different.

Interesting link! Just got told by our ASHP supplier that Glycol is a requirement of their guarantee! I re-did my flow / heat output calculations and found that 30% of their chosen Glycol will push my pump head requirement up by approx 100% I am now looking seriously at antifreeze valves! We sort of had this discussion back in 2022/23 (and occasionally since.. Not sure we reached any conclusions but the additional pump head requirement does not seem to have been featured very highly in the discussion while the difference in heat transfer does.

Yes of course sorry. Can't edit it now. That's all done.

That feels too big, do you mean l/hr?

Yes, that's why I use two and if they don't agree I dig deeper. On our system, which I will post for a sense check in a few days, I did it by hand then with 3 LLMs which didn't agree with me so I got them to explain why we differed and then reworked it until we all, well 2 LLMs and I, got to the same point. Which was better than going for my first calc because, it turns out, I had the wrong chart for pressure drop on the pex-al-pex and the TOG rating of the wooden floor wrong. Chat GPT worked best in my view.