Dan F

Control cable is often used to connect a CT clamp of some kind and allow the EV charger to do load management. Some EV chargers also have ethernet connection. Don't think load management is required, but depending on your main fuse size and expected load may be a good idea to have in place. This can be a seperate cable, as @Alan Ambrose said, doesn't have to be special all-on-one EV cable. 25mm2? Is this 50m+? Seems overkill otherwise..

We had 70mm open-graded tarmac laid on our drive just before we moved in 3 year ago. Since then, we've completed landscaping works and one of the few remaining things to complete things is to lay some resin. The result needs to be permeable and shouldn't pool. Permability after it was installed was great, with only a very small amount of surface water for a short period of time if there was heavy rain non-stop for a week. However, duing landscaping work, getting MOT and topsoil on the drive was pretty much unavoidable, and while it is still somewhat permeable we do have significant pooling in a number of areas. I haven't wanted to rush into getting resin put down as we don't want to proceed with resin only to find that the resin doesn't drain. The resin supplier has suggested a few things to mitigate this: - Drill holes in the tarmac, especially in areas we see pooling currently. - Use 10mm vs 6mm aggregate to increase permeability of resin. - Use 35mm resin on a grid, rather han 18mm directly on the tarmac as orginally planned (so resin layer can hold more water and water can distribute within resin layer). There are all great suggestions, and probably ones that we should follow, however I'd feel more confident if we could restore the permeability of the tarmac first. Pressure washing just move the fines around and doesn't improve things, so we need a different approach. According to Tarmac: However, the only versions of this that I have found online as large road-sweeper machine and charge £1000's day rate. Given drive is only 120m2 or so this does't make sense, yet I can't find anything smaller/cheaper or any self-hire options. I may well be looking in the wrong places though. I've wondered about hiring a higher power/capacity wet vaccum and then trying to do this myself and have also seen a product call "rotaryvac" [1] which I thought about trying to hire somewhere, but thought I'd see if anyone here has any experience of advice before I start experimenting..? [1] https://equip2clean.co.uk/products/kiam-rotaryvac-21-rotary-floor-cleaning-tool-with-fluid-recovery-vacuum-system

As I said, mine may have stopped at 80rps because it had already drosted enough, hard to tell, but even when mine is running flat out at 100%, defrost only reaches 80rps. I graphed this via ebusd/emon: I also experimented by setting NR mode to -50% (limiting compressor to 60rps), and defrost compressor still rose to 80rps. I'm can't say for certain that NR doesn't impact anything related to defrost, but it certainly doesn't constraint compressor to NR setting on mine. IGNORE THIS. FORUM WON'T LET ME DELETE IT FOR SOME REASON..

On my system, compressor speed on defrost only seems to reach 80prm (67%). It may go higher if needed, I'm unsure, but I haven't seen it go higher recently. Defrost compressor speed appears to ignore any noise reduction or eco modes, so AFAIK there is no way to limit defrost compressor speed or noise. My 7kW allow for -30%, does yours not? (I know the manual only says 40-60%).

80% was DALI or LED, and it was easier for electricians to use same cable everywhere and avoid any mix-ups. If you drivers are local to fitting you going to need more than twin-earth anyway, unless control is wireless or you have a seperate dali/dmx/tree/control cable. One example of where having this 5-core in place was handy was bedside lamps. We ended up choosing some wall lamps that have a wall light an a reading light, by using 4 cores were were able to give it a permannt live for the reading light (locally switched) and have the wall light on a loxone-controlled dimmer. We couldn't have done this otherwise once everything was boarded. It also meants that, when we finally source and install pendants we have option to use mains dimmed or DALI etc. You're right re: tree via 5-core. The scenario I was thinking about was a pendant in the hall, where we only decided later to use the Loxone pendant. What we did in this case was use the 2 cores (of the pre-wired 5-core) to supply 24v to the pendant, and then brought tree from the closest light switch.

We used 5-core in most places for lighting unless we knew that the lighting circuit was definitely going to be i) single-color ii) use a cabinet-based dimmer. Wtih 5-cores we could then: - power RGBW or tunable strips from with central LED driver, - send 230v + DALI to remote drivers (all our downlights and some other fittings are DALI) - send dimmed 230v - could even send 24v + loxone tree if needed. (albeit overkill core area)

Victron does too, and I'm sure others do too, includig Sonnen. Just need to check datasheets .

We had a consultant do our initial version, but i actually spent a lot of time learning it (bought the printed manual) and I used this knowledge to update and improve a few things that weren't quite right too. It's doable, but I know from experiencia how much time investment is required to even try to get it right. Also, how much of an impact things like exact glass specifciation, ventliation and how tress are modelled have have massive impact and change results fundamentally.

Start with inactive and try to find your correct heat curve, you can then switch to active which is more forgiving and adjusts better to solar gain etc. Expanded has its uses, but it's typically not a good idea. Adaptive WC is not really recommened either. Don't touch integral or hysterisis configuration until you've done the above, only then are you really in a position to understand if either of these need tweaking.

Expanded doesn't ignore energy integral. Adapative WC is typically not used or recommended. Energy integral is -60 by default, not -90. Don't think pressure should be varying like that, mine doesn't.

This is what you need: https://evanmccann.net/blog/ubiquiti/unifi-comparison-charts#fnr1 (it doesn't stay up to date for long ever though as they keep bring out new products)

You ideally want to get someone to do PHPP for you, unless you have a lot of time to spend learning how to use it, but I still wouldn't advise this really. - If someone else is doing it for you, you don't need to buy PHPP (they will use their own license), but you will need pay consultant fees of course. - If you are doing it yourself you also want to buy the detailed manual, will need to invest a lot of time and IMO you won't be able to as confident with the outcome vs having someone with experience and PHI certification do it for you. This is because there are so many details to it, and things that seem minor that it's possible to not fully understand, can have big impacts. (e.g. things like not getting ventilation assumptions correct, or not correctly adding all the fine details of glass spec, glass spacers, window frame size, overhangs, height of trees in your garden etc etc.)

I started out with all sorts of ideas/plans to control heating from Loxone, but the reality is that the best way to control heating is using the heat pumps own weather compensation. Anything else and you're just complicating things, creating potential maintenance issues and not really gaining anything (from my experience anyway). We have a Vaillant ASHP which has good weather compensation but also supports an "active" mode which ajusts curve slightly based on actual room temperatures which helps compensate for solar gains and works really well. In order to load-shift, I increase the desired room temperature during the night and reduce it during the day, this also works really well. Any type of thermostatic control, using room temp, doesn't work because UFH is in slab and room temp is very very slow to respond. I could have tried to use external controls to control ASHP based on slab-temp, but this adds complexity and isn't needed, and then you need to determine what required slab temp should be depending on outside temp etc.

Loxone intercom + nfc/keyboard is nice combo if you are using Loxone, costs a small fortune though, lot more than ubiquiti doorbell or even their intercom 😞 Doorbird (https://www.doorbird.com/) is another well-known brand for intercoms worth looking at.

Actually, no. Unfii express doesn't support "protect", it also has other limits I think. If you don't want to spend big money on a "dream machine" or anything rack mounted, the fairly new "Could Gateway Max" is one of the best options currently. https://techspecs.ui.com/unifi/unifi-cloud-gateways/ucg-max?s=uk What existing ubiquiti kit to you already have though?

Ours modifies flow temp based on room temp, not return temp!

This the the case with basic weather compensation. Most manufacturers have some kind of "room temperature modulation" option which wil adjust the curve based actual room temperature. This approach helps adjust for solar gain and high wind as well.

Which ASHP is this? What is hysteresis? My understanding is that with a target flow temp of 23C and a 7K hysteresis (as an example) with an open loop system the ASHP is going to run until flow temp reaches 30C and then shut down. Is this how yours behaves, or does it do something different e.g. mark-space ratio. I assume you much have hysteresis much lower than 7K? Otherwise, if flow temp does have to ramp up to 30C before ASHP shuts down, this risks temperature fluctuations and possibiity to overshoot.

It's not marketing (and I haven't seen it mentioned in marketing materials), it's a control strategy that is important to control cycling when heating load is less than minimum output. Without an integral-based control mechanism how would ASHP control cycles? Using simple hystersis would result in more temperature swings impacting efficiency and comfort AFAIU..

I know various people, including a Vaillant-approved installer, who have had to purchase and install their own replacement boards! What kind of "persuasion" was required? Is the new board already installed now? (make sure they move your cooling resistor over, and don't take it away with the old board. if you have one installed)

You don't have to disable anything, this is all automatic. We have UFH on ground-floor and Comfopost on first floor. (not a great idea as boosting MVHR to increase first-floor cooling brings in more warm air on ground floor) If you have UFH and/or fancoils on both floors there is no reason to install Comfopost no. In our case installing UFH on first-floor wasn't justified and given the cacluated cooling load was so low we felt that fancoils weren't justfied either. The comfopost was more of an insurance than anything else. What we realised living here though is that bedroom temperature can be quite important for some people to sleep well, and controlling bedroom temperature would have been very easy and effective with fancoils, but much harder with comfopost where you need to run it for extended periods of time and maintain the whole first-floor at a lower temperature.

2.8kw cooling is actually a fair amount for a very insulated house in the U.K, assuming you have shading/overhangs. Our calculated cooiing load was <1kW from what I remember. The thing is, and I didn't realise this at the time, those numbers are based on: - Water temp of 7C which isn't particulatly efficient. - Air temp of 28C But post-MVHR air temperature is never 28C assuming you keep internal temperature under control. If external temperature is 41C, internal temperature is 21C and MVHR efficency 90% you are looking at closer to 23C. And, if post-MVHR temp is 23C and not 28C cooling power is only 75% of what is quoted. On top of that, you can't really compare cooling power of Comfopost with cooling power of fancoil if you need run mvhr on boost to increase cooling, as it's cooling warmer incoming air, not air at existing room temperature. A simpler approach to stopping first-floor heating up via MVHR on all but the very hottest days is to turn MVHR to minimum during the day on very hot days. Not as effective, but lot simpler..

I have one. They are useful for ensuring MVHR doesn't gradually heat up the house when external termperature is high, but I wouldn't recommend for "active" cooling and if I was doing this again I'd definitly opt for fancoils instead. That said, because we have automatic external blinds and cooling load is very low we aren't in a rush to install fancoils and Comfopost does help keep first floor temperatures more comfortable than if we didn't have it installed. If we didn't have the external blinds though, it would be a different story. You do have to run the comfopost fairly constantly for this work though, and I've gradually adjusted circuit flow temp to ensure this doesn't cause ASHP to cycle like mad. I've put a Loxone automation in place to automatically turn on comfopost circuit when MVHR is delivering warm air to bedrooms, and boost if required.

Yes, any venetian blinds. We got them supplied with windows and control them via Loxone. Our are https://www.roma.de/, but AFAIU they don't sell into the U.K directly. Check with your window supplier as it simplifies things if you get them via then. Also, need to consider recess in construction for blind-box if you want them hidden.

Don't ask them for a price. Tell them it doesn't work as designed and you want it fixed under warranty.