joth

Seems like the research was published in January but a load of AI regurgitation has sprung up about it in the last few days. Original paper https://www.nature.com/articles/s41598-026-35389-6 Not sure, the reference "problematic" LEDs in the study were 3000K so it's already comparing incandescent vs warm white LED. Skimming the article all LED lights roll off at about 670nm but you need about 1000nm+ for the IR spectral component they talk about I've always felt the CTT [colour temperature tuning] is bit of a fad, especially in a domestic setting. But I can see a variant having a large benefit of having WW / IR dual channel emitters, and dynamically increase the amount of IR emitted based on various factors. e.g., more IR in winter when the inhabitants will have exposed to less of it naturally, and also when the loss of lighting efficiency is not so problematic as the IR is at least contributing to useful space-heating.

And down-sizing the ASHP to allow these long runs at a low deltaT without short cycling, isn't it? Our ASHP is way oversized so will bordering short cycle (5 min runtime, 10min period) when just cooling the slab to ~16deg. I'm still getting COP of 3.5-4. But it's powered from PV - if I could double the COP it would give me about 30p more SEG payments per day on these hottest days.

This is how I set mine up (6 years ago) on our ecodan, the problem is it's not just the FCU loop that needs condensation proofing but also the primary pipework that includes the filter, pump, sensors, divert valves etc. None of those devices are designed for being insulated, indeed there's a risk of pump burning out if you really did, and they gather condensation as easily as the pipework. Adding a second, much larger, FCU and keeping it at dew point is how I've used it for past 3 years.

Yeah by hot i mean "not cold", c.f. typical (historic) uk climate averages: 15-35°C is the ideal temperature range for LifePo4, which is much hotter than the uk average of 10°C

It's an interesting trade-off, as batteries like it hot and this move will reduce the efficiency and lifespan of the batteries when used in the cold, in winter. If you're only using them for PV self-generated storage, that's probably moot, but if like me you fill from overnight cheap rate then it's rather a hit. That said with 27kWh you have a lot to play with. I hadn't realised batteries could generate so much heat - presumably you moved the inverter too, and that was the actual heat-source? Unlike batteries, inverters do like it cold.

It's not so useful if you want to add on automations of any type - even a button to "turn off all the lights" is much trickier as it needs to inspect the current state and only pulse those that are on. Depends on what the end goal is really

My go-to is the Waveshare 32ch modbus RTU relay - been running a a few for over a year now, very stable. However i can't see evidence of CE mark now. Not even the old incorrect kerning "China Export" variant

Final follow up on this L9 error: it was not (really) the flow sensor or the kinked up flexis, but a load of limescale build up in the ASHP heat exchanger. Full write up in new thread:

OK early signs are (very) promising! the "bucket test" delivered 24 l/min, and I've refilled the system (adding a bottle of F1) and it's now doing a DHW cycle at 16 l/min. Still not quite where I'd like it to be, but far better than the 10 l/min or less it's been hobbling by on for the last 24 months .... Interesting... I'd always thought using such occasions as an opportunity to flush out the crap and refill with clean. But yes, or course ... if scale is the problem refilling it is introducing a whole load more calcium carbonate ontop of what's already built up. I guess running the drain off through a fine filter would help sift off the worst of the mess coming out. Challenge is where to put the 100l of water when temporarily draining down the system ... although in most cases I can isolate the volumizing tank and leave the UFH loops untouched, so probably a quite doable. I'll read the heatgeek page and ponder how to attack this next time I do some service on it. Good news is I do now have this nifty wee pump so cycling water through it is much simpler now. 15 quid well spent https://www.ebay.co.uk/itm/187759301764

Thanks @JohnMo that's super useful info Today's project will be just to descale (the second batch of DS3 is currently resting in the PHE), flush, flow rate test, lob in a bottle of Fernox F1 and set the system going for a few days to validate I'll definitely look into the VDI2035 for a follow up project once the basics are back working

- Probably nothing ASHP specific about this question, but I'm specifically asking in relation to an Mitsu ecodan 8.5kW ASHP - This is the next instalment of my ongoing debacle about flow rate errors, link below. I now know this is not a sensor or plumbing error, but the plate heat exchanger is completely blocked and needing clearing. My plan is to get pickup some Fenox DS3, mix it up with hot water and pour into the PHE. Obviously with the whole lot disconnected from the primary circuit, and using appropriate PPE. Then flush it all with mains water. If that doesn't clear it up, then I probably need to get Mitsu in to replace it. Interested if anyone has had similar problem and how they attacked it?? ======= More background: 1/ original post 2 years ago, thinking it was flow sensor error, then thinking it was kinked flexi pipes. 2/ Subsequent update: I bought a cheap submersible pub (Makita LXT powered) and did some simple flow tests into a bucket: - without the PHE inline: 35 l/min - with the PHE inline: 4.5 l/min ---- just a trickle, and critically less than the 5l/min minimum required While flushing it through I initially saw plenty of white-ish sand-like granular dirt come out. Odourless. Presume this is limescale debris: - We're in a very hard water area; originally (2021) the system was filled (by others) with softened water, but since then I heard that's not advised so on subsequent fills I used mains water and Sentinel X100. It originally had glycol but I've never bothered to refill that. It's been emptied and filled numerous times due to FCU and volumizer additions, as recorded elsewhere on here. - It has a Fernox TF1 filter, I've regularly cleared and flushed that but never had significant dirt come out - but perhaps a bit of grains of limescale thinking back. My hypothesis now is that this was always the issue, but every time I messed about replacing flexi-pipes and blowing out the airlocks, I was also dislodging a bunch of limescale each time, but it's still had a constant build up that needs to be properly descaled.

I ran condensate drains but they're always dry because I run it over dew point. I did run it (much) colder for a season, but the condensation on all the plumbing gubbins was too much. Pipes are easy to insulate, but circulation pumps, 3 port valves, magfilter, flow sensor, etc not so much. It quickly started to look a real mess. Adding a second (much larger) FCU greatly reduced the need to run at such low flow temp

We used some uplighters from phos https://www.phos.co.uk/products/uplights Excellent build wouldn't hesitate recommending them as a manufacturer, if you're happy with the price, but honestly not sure I'd bother with uplighters indoors if doing it again. Tricky to install, have caused numerous maintenance issues (floor boards settling skewing them, doors settling catching on them, bare feet snag on them), and the actual lighting effect is often missed other than the occasional blinding of eyes when walking over them

Yes! We talk a lot about renewables requiring grid reinforcement, but in many cases renewables *are* the grid reinforcement. Especially if a battery is also installed at the far end of that long bit of wet string.

Fair point 🤣 What I was trying to say was it would be unnecessarily complex to try and design something elaborate into the standards requiring "intelligent" collaboration across a system of inverts communicating with each other, when you can achieve it within the existing pretty dumb standard.