CotswoldDoItUpper

Get an underground one. Cost to install LPG boiler is significantly less then an ASHP, fuel costs +-10%, no idea about servicing an ASHP but our boiler is £100/yr. I can see benefit for ASHP if combined with decent size solar aray, but that’s even bigger capital expenditure. Personally go for LPG and spend the extra saved on insulation. I’d design the system to be able to just swap the lpg boiler for an ASHP at some point in the future if needed.

We are having the same dilemma but we’ve just fixed our LPG at 34+vat p/L for 2 years with Avanti Gas. Kinda made the decision for us! Despite wanting to go ASHP route, we’re sticking with the existing set up and not spending the initial outlay for the ‘green’ alternative.

@severnside think we might be getting a new charger then! Been using the Granny charger for 2 years! @SteamyTea think we use about 8-9000kWh for normal domestic usage anyway so hopefully the PV will cover some of that load as well as the cars.

I guess we would look at maximum yearly usage. We have an annual use of around 20,000kWh (2 x EV) so will easily self use. I’ll have a look at PVGIS and work done things out. Didn’t realise it could do hourly data too! Does it take into account average sunny/cloudy days?

Also did a 15mm mains pressure (wrong side of the stopcock) job recently. Couldn’t find the main shutoff on the road so didn’t have much choice! That was even more fun, furthest spray of water was nearly 12m away!! Maybe should have used pipe freezing for that… think I’ll shut off the UFH manifold to protect it and close every valve I can and then go ‘live’ after releasing pressure with a drain valve. Might need to refill with less inhibitor then.

I’ve done quite a few before, but always fully drained the system. Just trying to rave some effort. If the system was drained I might take a bit longer without rushing! I capped some 22mm pipes when we removed the rads in half the house whilst the system was pressured (boiler off tho!). I don’t think I’ll do it again!! Pipe cutter and push fit to hand and I still would have been drier if I’d had a bath!

I’m replacing the old rads with larger ones (wider and deeper for a lower delta flow temp) all the new pipe work is done and in place, just need to cut out the old copper and fit a compression to join the existing copper to the new plastic at each end. Doing that on 4 rads, 6mins each I guess. @PeterW I had my eye on this… seems to have good reviews? But if experience on BH tells me anything, it’s to listen to those on BH with experience! https://www.screwfix.com/p/arctic-products-pipe-freezing-kit-300ml/900fj

@ProDave what about pipe freezing? I only need it isolated for about 30mins max I guess? Does it work or is it a con?

This is interesting, how would you recommend siting the panels? I’m trying to work out (sear Stroud) what angle would be best for all year round use (4kW array, 3.6kW inverter).

Damn. No, they’re downstairs in a part of the house unsuitable for UFH. Full drain down needed.

Our LPG boiler feeds an s-plan where the two zones are 1: radiators and 2: buffer tank for UFH. if I wish to work on the radiator zone, can I just shut off the valve for the radiator circuit and drain just that section? I don’t really want to have to drain and fill the whole damn thing just to reconnect a new radiator!!

The guy quoting said that it would be ok. I can’t have any larger without paying a small fortune to the DNO to upgrade the whole system, despite my neighbours having a perfectly acceptable 7kWh array!

So basically if I go for a 4kWh array and a 3.6kWh inverter the output will always be limited to 3.6kWh (I assume) therefore angling the panels to a maximum benefit reduces my output in summer months anyway to 3.6kWh which means the inverter isn’t clipping as much over production off in the summer and I’m still getting the 3.6kWh but my winter production has increased by a significant margin. The angle is somewhere around 70%, similar to @Marvin’s 18deg off the vertical. think I might turn them into some sort of brise soleil for the garage! am I missing something? Most solar farms I’ve seen appear to be set around 45deg.

Does anyone change the angle of their PV between summer and winter? Just jacking up the back of a ground/flat roof mounted system in the winter and lowering it in summer to try and optimise gain? Up once and down once in a 12-month period, nothing more complicated then that! Just thinking through the design for my flat garage roof mounting and wondering if it’s worth it.

True, but I have gas in my tank which I pay for after it’s delivered. If they go t*ts-up then I haven’t lost anything!

I’ve just fixed our bulk (2200L tank) LPG supply at 34p + vat for 2 years with Avanti Gas. Works out at a shade over 5p/kWh.

Is the TS4 not an optimiser? What would you upgrade it too?

Just received this from ITS Technologies… Seems good and will have a payback of about 4years? Quotation(ImPV05717).pdf

I’m looking into this too. Been recommended here: https://www.itstechnologies.shop/collections/12-solar-panel-kits-buy-online be interested if you find anywhere else better!

Trying to sort the wheat from the chaff when it comes to PV suppliers. There appear to be many rip off merchants out there and even eBay as well! Can anyone recommend where they bought their PV from? Is it best to get each component from a different supplier to get the best price overall? TIA

We already have UFH, buffer tank and rads sized for a low temp system with an S-plan instalation between buffer tank and rads. Our existing 15yr old LPG gas combi might die at some point and it’d be good to know that I could do most of the install myself and have a good plumber look over it. Would obviously need to hide a cylinder for DHW somewhere, but that’d probably go where the old boiler comes out. I’d probably change the s-plan to switch the heating (we now have digital TRVs on the rads so each one is it’s own ‘zone’) and DHW flows separately. this may be a moot point seeing as our LPG is currently 5p per kWh (34p+vat/L), so much cheeper then elec for an ASHP!

I’ve only just read about the type of ASHP that have all the gubbins in one box outside and only need a flow and return in water to/from them. does this mean you can effectively do a ‘simple’ DIY installation? Obv no RHI payments or similar, but surely how hard could it be?

We had a similar conundrum on a previous project… went with ICF in the end due to access. You often need a bloody big crane to get the SIPS into place! Good luck!

Ultimately @Indy, if you would love to come home to this design after a tough day the go ahead and build it. It’ll be a safe warm environment for your family, which has to be the most important thing. Everything else is just taste. Not everyone likes Gaudi buildings, but he built them because he liked them. As long as your sensible with glazing/insulation etc. so it’s a comfortable place to live then you build what you want. If this is a design that you like, then go for it, despite what others are saying. Having said that (and caveat with I don’t know what your brief was) it does seem underwhelming for an ‘architect designed’ house. I’m sure you could go from something you like to something you LOVE. I wish you the best of luck with the project whatever you do, when it’s done I’m sure you’ll be proud of the achievement whatever design you settle on.

If it’s a ground mounted ‘fence’ that’s over 9sqm does it need planning permission? #GettingAroundTheRules