Avendit

Well, I don't think I did anything, but that's it running now! Is there a lower outdoor temp it won't run below? I was playing in the evening last night, so possibly just too cool to kick in.

Sorry, I thought I had, apologies

It has zone & sensor set to use 'room temperature: water sensor' to sense demand so I can use a compensation curve. When heating is 'on' it then keeps its loop at the set temp, which keeps the buffer at the temp, which keeps the heating at the temp. I run open loop in winter, so although I have room controls, they are all set up at 22, and I don't think the (heatmiser) heating system is electrically or logically connected to the HP. That said, I can create 'demand' by setting a room temp up to 30 degrees when it's warm to get the heating water circulating, but the buffer and HP loop stay at 20, despite a target temp of say 12. I'm hoping someone that used the process from the manual above to unlock cooling can confirm if anything else was needed.

(Wouldn't normally have it on at these temps, or set this cool, just did this for the pic). But no activation of the HP and therefore no cooled water ☹️.

I've just tried this but am not getting cooling. Unit is cooling enabled, I have a target temp of 12 configured as a 'direct' temp, cooling shows up through the whole UI, but it's not firing up to actually deliver cooling. Does something physical need added as per post 2 or 3 from the start of the thread? Either a terminal short or cooling stat? For heating I'm just using the water temp to call for heat, so no heating stat or connection to the heating system.

Such a shame as it sounds like you have a perfectly effective install and you are stuck between a rock and hard place. TBH, I would patch up the hole that has been made and find some new buyers. The the opportunity of the exposure you have to take some damp readings (damp measuring devices available in B&Q for not much) and try and build up that info pack as best as you can retrospectively. Perhaps its possible to find in advance which mortgage lenders will support you and just inform viewers? Change plan and extend this place rather than move? (sorry, clutching at straws) Seal the loft access and get another surveyor?

Well, have found the answer to at least the annoying wall today. I took the skirting off today to inject a tin of spray foam so the wall is now actually joined to the floor (much improvement around the toes, well worth the effort!) and found I had the build up wrong. I thought it was Insulated plaster with 5cm bonded EPS brick 2cm cavity with 1cm of EPS in. brick render The first layer turns out to be just normal plaster on a loose 3cm sheet of EPS. So obvious answer is next time we are decorating, its plaster off, EPS out, PIR in and thick insulated plaster board on top. With 10cm insulated board on top of 3cm of PIR I should get around 0.14, which brings that wall into line with the rest of the building. Small condensation risk, so need to get a good vapour barrier in there somewhere, but choosing that is a problem for much later. Just the question of the attic to go. I still don't like the idea of a non-breathable barrier up there, given its all breathable just now.

https://www.property-care.org/write/MediaUploads/Technical Documents/SprayedFoamInsulationInspectionProtocol_March2023.pdf this is the direct link to what you need. Any details left by the previous owners that would let you build up the 'pack' mentioned in page 9 onwards?

I wouldn't want to use it for doing real calcs, but for quick and dirty relative calculations, I use https://www.vesma.com/tutorial/uvalue01/uvalue01.htm Modern blown beads with glue shouldn't settle should they?

Can I reasonably add anything up in the attic? If so, any suggestions for what?

Is it mostly between rafters but with some overspray? Or over the rafters to a decent depth? If its just in between plus spillage, read on. If the timbers are visible the mortgage company should relent (some definitely will). Check with the lender first, but one suggestion would be don't remove all of it, just the overspray onto the rafters. Big knife like a bread knife and saw it off down each rafter in turn, no more than a few hours work hopefully. 11 years of no trouble show that the roof was structurally sound (you can use closed cell for strengthening failing buildings, which is partly why it has such a bad rep as it gets/has been used for this inappropriately quite often. If only the cowboy spray foam people would use open cell the whole spray foam industry would be in a much better place :(. (We have open cell spray foam so have to deal with the misinformation problems quite often in conversation. Fortunately prior to having the spray done we already had a lifetime mortgage deal so have not had to deal with this first hand.) If you have to remove, will the EPC also need redone and the deal re-negotiated as a result? I'd say you are taking value out of the house if you remove the insulation :(. You may need another buyer at that stage :(. Only other option I can see is coming to some risk management agreement with the surveyor and lender. They are probably worried about damp - if you can find a way of testing or monitoring for that and agree it will be professionally done yearly (or something) they may lend? Then offer the new owners 10 years worth of those fees - may be cheaper than the other options

Hi all, I have a 1960's chalet style house that we have done a lot of work on so far. As part of an extension, heatpump and new heating system install I had open cell sprayfoam added under the suspended timber floor (100mm) and around all the room in roof spaces (150mm between rafter) at roof height. We have since then added 90mm of EPS EWI to most of the walls, and Solar PV. We have also added MVHR to most of the house after Jeremy sung its praises on a different forum. The EWI walls work out around U0.17, and the roof U0.24. I have 2 areas I'd appreciate some advice on. The first is the roof. It seems mad to have worse insulation on the top of the house, so I was looking for relatively easy DIY-able ways to improve this as much as possible. I am only looking to do this in the main attic space - about 50% of the surface area. There is no space to do anything in the angled celling areas of the room in roof (I could/will add insulated plasterboard when we next decorate, but its not a big area) and I can't get back into the eves without incurring the wrath of the decorator (also me btw). One suggestion I thought of was to use superfoil under the sprayfoam for this - its not cheap, but my DIY skills aren't amazing so having something I just unroll and staple in place then tape up would be very much preferred. It would also conform around the imperfect spray foam surface and generally simplify things vs installing anything solid. It also seems to be price competitive at the 45mm thick vs EPS. Talking to the manufacturer they were reasonably insistent on the vapour barrier version of the product, where I had selected the vapor open version so as not to mess with the current building. And I can't see using a vapor closed version over half the roof height being smart? Is taking half the roof from 0.24 to 0.15 and leaving the rest just a dumb idea? if doing something is OK, is superfoil a decent approach in this case, and if so, vapour closed or open? To be clear, having looked at it I wouldn't choose it for any other application. It just seems bettered on all fronts by something else except here where I just need to unroll and staple. The second is a wall that was on the party line, so I couldn't add EWI - I don't think I could even render it legally speaking, that's how on the boundary it is. Its a weird build up of 50mm insulated plasterboard, inner brick, 20mm cavity with 10mm EPS boards floating around, external brick. I can't find any good solution for this. My architect things that there is already a cycle of condensation and evaporation in the wall, and adding any internal insulation just makes this worse. I can't add anything into the cavity, and even if I did 20mm wouldn't amount to sod all anyway. Any smart ideas? Currently guesstimate is U 0.42 over 25 m^2. Thanks massively!