joth

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.

In principle it's quite easy, unfortunately the grid would need to be re-engineered. It's also unnecessarily complex, from the grid operators view. Scaled over 10s or 100s of houses, the current system of individual inverters just shutting off when hitting the threshold has the system wide effect of gracefully reducing the amount put into the grid (as each inverter shuts of one by one, converging to a stable number exporting during periods of strong sun and low consumption). It just sucks for the individuals that get hit by it first as they don't get to self-consume any of their solar if the inverter has safety shutdown. What can be very frustrating is if the inverter is on a long AC line within the property (after the meter) then it may see >253V even though the grid itself outside the property is no where near that. It would be tempting to say either allow the inverter to exceed 253V so long as it is export limited (to zero export) or if there's a voltage sense at the meter tails. Of course, this is messing with a safety system, and also risks damaging other equipment in the home if that starts seeing > 260V, so a terrible idea in practice. The answer here is move the inverter as close to the meter as possible, and ideally have dynamic export limitation (to do near-zero export when it sees the grid is over 250V) and then it will never need to trip over 253V while still satisfying the home's own demand. A DC-coupled battery also helps capture what would otherwise wasted solar, oc.

In my experience larger pipework and some degree of zoning would be needed. Most of the year I'd like additional cooling ij the upstairs rooms, even though the ground floor is in heating mode. I guess getting one mvhr per floor would be simplest, although adding yet more cost onto already expensive system On the plus side, at least in my house redoing the FF pipework with larger diameter would be simple enough. (Indeed I've essentially already done that piecemeal, by adding ducted Fancoils and then forcing air from outside directly into those ducts at night time. My own mvhr uber bypass). All that said those are specific challenges hit in our passivhaus retrofit, and regardless of the improvement opportunities I'd fit MVHR again every single time. The system efficiency and comfort while avoiding and moisture/mould risk is incredible. And the reduced dust build up a real plus.

Scratching my head - G98/99 and PV connection is managed by DNOs, not by "the" national grid ("National Energy System Operator"). But also National Grid is the name of one of many DNOs. So does this statement apply just in their DNO patch, or sloppy journalism actually meaning all "grid" DNOs, or has the definition of Nation Grid changed yet again while I was out? A link to the original source press release would no doubt help.

One question is your priority documenting if for quotation, construction, or post-completion maintenance purposes? My experience so far is: - For quotation a comprehensive schedule (Google Sheet) of fittings (type, room, wiring required) is sufficient, and indeed preferable to detailed drawings for the reason Dave lists. - For construction, drawings with plans and where relevant elevation show location of each fitting is necessary, but often sockets and lights gets moved about during 1st and even 2nd fix. - For maintenance, ideally one would also have drawings showing the hidden pipework and wire routing. Realistically this would HAVE to be done after 1st fix (but before walls closed) because I've never yet met a trade that will actually follow plans: often times unforeseen practicalities means they can't, but in all cases they will have their own habits and preference and just do it the way they think it should be done rather than how any plan says it is to be done. And in practice I've yet to see anyone actually create such plans: there's too much rush to get started on boarding. These days your best bet is some comprehensive photos (360degree camera is ideal) of every surface of every room. The exception to all the above is if you're literally doing it all yourself in which case you can control a lot more!

Plug PGSPDY2 requires tool TRCSPDY3 https://www.speedy-rj45.com/cat6a-shielded-feedthrough-plug Plug PGSPDY3 requires tool TBSPDY2 https://www.speedy-rj45.com/shielded-plug-for-xl-cable Well that's not confusing at all 🙄

I've typically bought from https://bownetcms.co.uk/ as they had fairly good pricing on CAT6(a) too, but I haven't comparison shopped this for a few years. Make sure you have the correct compatible crimping tool. And buy some spare blades while ordering ... And remember to use the little plastic carrier to arrange the cores correctly before pushing them through.

https://www.speedy-rj45.com/shielded-plug-for-xl-cable

Did they give a particular reason? Curious that a few suppliers suggested it, specifically for bathrooms. Guess because not needed for fire regs? But still curious if any reason for there aside some marginal cost-savings. I'd definitely go with opening, even though we rarely use ours for cooling much as we'd like to: too much street/train noise when the windows open, plus it lets a lot more dust in. (And smoke if neighbours have the coal fire going). Obviously that's all situational. We actually got the master ensuite with flyscreen pre-installed, thinking it would be useful for summer cooling, but in practice is still allows too much noise in but totally ineffective at cooling the bedroom. (Yet makes for an uncomfortably cold bathroom in the morning and makes the UFH in there work harder!) So anyway yeah we never use the opening on it aside for cleaning/maintenance, but I'd still want a stronger reason for not getting it. The next owner of our house maybe German and want their Lüften ritual.

If you buy one of these (first random example I found, not a specific recommendation), I'd wager the driver can be swapped out for a dimmable/CTT/smart one your choice. It comes with a 300mA CC driver and inline switch to select temperature: my expectation is cut the switch off, and there's three cores coming out the back of it that feeds two LED strips internally to the fitting, for warm and cool white.

That one was LED strip and appropriate driver. IIRC it was from DLD with an LTech driver https://www.darklightdesign.com/architectural-lighting/led-tape/112654/ https://www.ultraleds.co.uk/ltech-professional-24v-dali-constant-voltage-led-driver-36w-ip20

My experience is kitchen cabinet supplied light fittings are massively marked up rubbish. One project the customer paid hundreds per cabinet for them just to rip them out and replace with some quality Dali fittings (which also added CTT support). The pre fitted stuff was 12V non-dimmable inconsistent temperature, and random switch on latency. Essentially the cost just went into having the kitchen company route out channels and provide some glass bases for the cabinets. Can't really help with the OP other than say most slimline panel fittings are just an LED strip and a diffuser internally, so like the case i mentioned above you may get some mileage finding a quality fitting and pairing it to an appropriate constant current LED driver of your choice.

Happy to say I've not touched the Smartrhings in years (decades?), but Home Assistant very much is a single point of failure. Which was the point I was making there: aside KNX anything that doesn't depend on an in-home SPoF is probably depending on a cloud one instead (even just for authentication /ownership management) - which is probably worse of two evils. And even KNX doesn't really count as to do any interesting automation you need a PLC server which of course is itself the SPoF. Home Assistant certainly is all local easy to change owner at an administrative level. But handing over an entire installation as part of a home sale is a brave idea and I'd love to hear actual case studies of anyone attempting let alone succeeding it. My experience is Either HA is doing purely "nice to have functionality" (ovens and lawn mowers) in which case no compelling reason to leave it in the house. Or it's running the BMS - lighting and heating - in which case really hope the new home owner is keen on being sysadmin

The problem with all the consumer smart home stuff I know if is what happens when you come to sell the house? Does the new owner need to re-pair every individual lightbulb, blind and heating actuator into their own cloud account? (Or more often, multitude of accounts). Not to mention what happens when the cloud provider gets bored and shuts it down. Centralised systems are only marginally better for succession rights, but for the most part they offer some glimmer of hope. It still requires the seller to transfer ownership (e.g. hand over the admin password or project file) for a smooth transition. But at least I can point to examples of this working out. ... Put another way - an "non-centralised" solution is worse than useless if it exchanges an in-house single point of failure for a cloud-based one.

The pump (UPS 3) is not setup to modulate, it's running on speed three (maximum, also factory default). I don't have anything at all in the system intentionally reducing flow rate. As i say without the monobloc in line it happily circulates at 24 so yeah, agree it was never great even when first commissioned. and now it's barely operational

So thanks to @SimonD I have the correct length flexis and looks a lot neater, definitely not kinked now. But still... Flow rate remains stubbornly sat at the minimum 5l/min. And gave another L-9 error earlier this month (typically enough, it happened we were away and had a guest staying to mind the house). So I've done a bit more experimentation. Having water bypass the monobloc, so connecting the external flexis directly together through a M-M coupler, suddenly the flow rate jumps to 24l/min. So there's no problem in principle with the pump or pipework. It something about the heat exchanger. Pushing mains water (from the outdoor hose) through the monobloc it seems to run freely and clear. For shits and giggles, I reversed the flow direction through the heat-pump (so AFAIK pumping the primary water in through outlet connection...) the flow rate is a wee bit better, 7-8 rather than 5. I'm still at bit of a loss. The heat exchanger seems a fairly simple passive device, can't see what could have failed in it to restrict flow. There's no other components in the monobloc that would seem to affect the water flow rate. And again, it was over 15 l/min when first commissioned so it's definitely declined with time. I'll try again to see if I can an authorised service rep in , but so far no one has returned my calls.