Nickfromwales

According to my basic maths, 800w and upward. They’re far more aggressive than a typical MVHR fan. So, around 3-4x the power or more.

You also wont want to suck all the build dust into it either. 200w or less fan size will do very little. You should seal u the MVHR ducts when you depressurise, if you've connected to atmosphere?

Crikey....... You need to get the cables tested BEFORE any other works progress / get covered over. I'm out.

Insulation resistance and other such basic tests are irrelevant to the OP then?

It’s when you assume nothing can / will go wrong, and you don’t exercise diligence, that's when it does go wrong. This forum dispenses advice, so take that as good advice, or with a pinch. Time on the tools, hands-on practical experience, qualifications etc cannot be replaced by a few paragraphs here. Nobody yet mentioned that they did / did not carry out the checks as per @ProDave‘s comment above, so we can assume they were blissfully unaware of the risks posed by NOT doing so and then self installing their PV. I’ve heard enough horror stories, and instances where an individual has been electrocuted, to be less blasé.

PV is inevitable, so if you fit a combi you’ll be stuffed for diverting excess into DHW all summer long. No free hot water for you then!! “Efficiency” needs to be elaborated upon, and is an overall summary vs just what that appliance choice will provide you with. Do not be short-sighted here

They don’t get much quieter tbh, as is the same for my sons attic unit. Also needs an 8” discharge hose to atmosphere. A split will give you cooling with just the sound of a fan oscillating. I’m looking at a split for my other sons room as there just isn’t any floor space left in the room that I wish to sacrifice, so a unit on the wall is the weapon of choice by default. Maintenance of the in-room units is a drag, as the tiny gaps between the heat exchanger fins catches dust extremely efficiently, and I have to take the unit outside and blow it all clean with my compressor and an air ‘gun’. You can see how quickly and by how much the output is affected by even the start of that accumulation of crud, mostly carpet / clothes fibres and then the fine particle dust catches in that. A PITA, but, in fairness, without the attic unit running 24/7 that room would be unusable. I am likely to go for a split for my other sons room because a) I want to put AC in every bedroom by the end of the year, ( 8kWp of PV going in soon, expanded by another 4 also by the end of the year ), but his room ( rear extension 1st floor ) is 9” brick and it is just unbearable in both the peak of summer and the depths of winter, so that unit will likely need max output focussed in that room plus one other less adverse room, ergo the split will likely feed 2 rooms with his ‘prioritised’ as iirc you can do with certain decent splits. The other 3 less adverse bedrooms can come off a second split ( feeding the 3 rooms ) and that should suffice. Was hoping to get DIY Pre-gassed units for self install, but I’ve decided to just run all the gas lines, condensates, cables etc and dry mount the internal and external units and then get an AC fitter in to gas, test and commission in one visit. I’m way too busy with work to do EWI, and IWI is not sn option either for a bunch of reasons, but the 9” brick extension is gagging to be EWI’d in honesty. Time is my enemy.

Buy with you CC

I’d give you my PV partners contact details, but I know he’ll say December. PM me if you get completely stuck.

Anybody know if the Tigo optimisers drop the open-circuit voltage to <1v ( like the Solaredge ones do? ). Apologies for the hijack, blame the beer. I am COMPLETELY innocent. Disclaimer: Innocent when sober = questionable at best.

All kneel before God ( aka beer )

I’ve been competent with complex 1ph and 3ph electrical design and installation projects, in both the domestic and the marine environment, and am taking delivery of my own panels imminently. I’ll be completely honest, even MY arse is twitching over the DC-related-death likelihood. I’ve had more AC shocks than I can remember ( memory loss probably caused by these lol ) and only one got me worried, but DC is a different beast altogether. As an aside; It would be such a shame to die now, as my children are 11, 13, 15 and 18 years of age now, and over the last few months I’ve started to become quite fond of them…….

Yes, just trying to be pragmatic before the Shipyard kicks in

Are they optimised? If not, beware of getting frazzled installing these during the daytime. The real risk is going + to - per panel in sunlight, or the then elevated risk of connecting a string and getting quite high DC available across the sum of the string. Pretty serious, life changing juice available per string. If you make the single core DC cables off to the rotary isolator first, then lock the isolator in the off position, and work back from there up panel by panel you will reduce the risk ( not eliminate it ). If you have any doubt, please do not carry out this work.

System sized for near zero dependency on grid, ergo nothing to export.

And a very spectacular thing when done poorly…. If you could section each area off and install screed rails a-la @Onoff, and make some robust straight-edge’s up, you could get it close enough to use SLC after the initial ‘pour’. If you plan and strategise then this is doable, but do not even DREAM of trying to get the lot down in one go. Try one area first and see how big your balls remain What are the sizes ( LxW ) of these areas? Possibly make a straight edge up for the widest room first, use it there, and then you can retain and cut it down for each smaller floor.

Another pedigree thread for the archives….

Yup. I will dump into AGM’s or DHW preheat cylinder ( TS with a DHW coil feeding cold inlet of combi or diverting straight to hot network ( Caleffi valve to be fitted ))

Wait until they go on holiday, and then order 40t of hardcore to be ‘gifted’ upon their driveway. A gift once recounted by a few B&B owners who decided to club together and buy one old hag a ‘present’ for slagging all the other B&B’s in her street off anonymously on ratings sites, and then telling someone who then decided to share her secret. Bingo Bango. 👊.

How long a pipe do I need to access volcanic heat from the earths core? Just asking for a friend…..

Hire a proper cyclone vacuum, as they have the various staged filters for fine dust, otherwise you’ll be cleaning those baby vacuums out every 15-20 mins.

Yanks and Aussie off-grinders bury decommissioned fuel tanker trailers as thermal stores for summer harvest / winter yield, so absolutely can and is being done. Would need to be massive to succeed, but temps of countries that have done this must be of relevance?

I think everyone on here should sponsor you with £1 to fund it, and see what happens 👍.

You can get 80+ out of a split I suppose the thoughts were aligned with how ‘we’ charge a passive raft with heat here, just the slight issue of additional waste heat losses from the TS become a deciding factor. Could still reap benefits from a dwelling which has PV + ASHP but little or no medium to store heat energy for slow release. The TS may well be a good candidate if you went with a low-temp monoblock ASHP, and have already installed smaller radiators? If for space heating only, consider no TS, just a small buffer, a high-temp split perhaps?

It may just need the cartridge commissioning also. Installation manual will tell you how to do this. It’s quite simple, just needs a screwdriver or Allen key. 👍