Temp

I think 150mm upstand is normally the minimum recommended. That would be 150mm above the tiles. If a hidden gutter is used (as @PeterW said) it would be 150mm above the bottom of the gutter which would be lower. Hidden gutters can work with zero height above the roof if the gutter is deep enough. Image from here. https://1stassociated.co.uk/box-gutter-sketch.asp If this is an existing roof I think the main issue is likely to be a rafter in the way (fixed to the wall).

Not all lenders recognise all warranties. The Council of Mortgage Lenders used to have a database. I think the CML is now part of UK Finance a new trade body. Perhaps suggest the buyer go back to his lender and ask if he can take out a PCC? Or try another lender?

Pure speculation but.. Perhaps if the pump is failing the controller thinks it needs a defrost cycle. If that involves pumping hot water from the system/buffer it seems reasonable it might generate a defrost circulation failure error. Perhaps it tries to do a defrost but because the pump is failing the flow temperature falls and it thinks its out of hot water to do the defrost. I'm making this up as I go along so happy to be corrected if this is wrong.

Our down pipes go straight into 110mm vertical drain pipe at ground level with a rubber boot seal/adaptor. No leaf traps anywhere and lots of trees. Get a lot of leaves in the gutters but the drains seem to cope with any that go down. Do the hedgehogs save you having to clean out the gutters or make it easier/harder?

So are they saying you need a nice big buffer tank full of hot water to defrost it when it ices up? Could "Buffer tank (is used)" mean "Buffer tank (is used up/cold)"?

Oops I miss read that as DEVICE circulation error whereas it says DEICE which is same as DEFROST.

Google found this but I don't know if this is a totally different model.. https://heidi-air-conditioning.co.uk/assets/downloads/user-manuals/panasonic-aquarea/End-user-guide-F-and-G-series-A2W_HR.pdf "H65 Defrost circulation error Reset once if reoccurring contact your local Panasonic installer, quoting fault code"

Approved Document L para 2.42 says.. "Reasonable provision should be made to limit heat losses from pipes in accordance with the Domestic Services Compliance Guide.".. https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/697525/DBSCG_secure.pdf Not sure if that mandates insulation for hot water pipes as I've not read it.

Efficiency has many meanings. 100mm Rockwool Cavity Insulation Batt Thermal Conductivity: 0.037W/mK R-Value: 2.7m2K/W 100mm Celotex GA4000 PIR Insulation Board Thermal Conductivity: 0.022W/mK R-Value: 4.5m2K/W So I would expect.. 100mm Celotex to be equivalent to about 168mm Rockwool. or 60mm Celotex would do similar job to 100mm Rockwool. Your mileage may vary. Celotex is slightly harder to install without gaps as Rockwool is compliant but I think that's mainly an issue when fitted between studs rather than over ply.

It might also be possible to replace the relays if they have numbers on them.

Think the temperature sensors use edge connectors on the PCB so no white plastic connector required on the PCB ??? This one also looks pretty similar but I cant see any matching numbers.. https://heatingpartswarehouse.co.uk/product/grant-temp-control-pcb-mpcbs96/?gclid=CjwKCAiAt9z-BRBCEiwA_bWv-BpM0mzS3DI_vjhm4RO_cSiHXdoWQBZ81HHJ1jwGZz9wPVopieemaxoCa30QAvD_BwE Says.. "Suitable for the following boilers: Grant Combi V3, Grant Vortex Pro Condensing Combi (After Sept 08)"

The BCO was being subtle. He could have said "I'm going to fail your entire house for non compliance with part X paragraph Y subparagraph z and if you don't comply by my next visit I will be initiating enforcement action ". However BCO are generally more amicable than Planning Officers so instead he said "Those hot pipes might damage your Louis Vuitton" in the hope you might get the hint. Seems he failed ?

Ground staff looking after War graves in Europe told to return to the UK or face 50% pay cut.. https://www.thesun.co.uk/news/13467994/staff-world-war-graves-uk-50-per-cent-cut/ I think I would be checking my contract of employment and labour laws...

I don't think a home office is considered a "habitable space" but the work is probably a "material alteration". https://www.planningportal.co.uk/info/200130/common_projects/25/garage_conversion/2 https://www.planningportal.co.uk/info/200130/common_projects/56/working_from_home/2

Does it have to be inside the ASHP or could it be anywhere in the pipe run?

Welcome to the forum Matt. Sounds like an interesting project.

What are the rooms going to be used for? If these are going to be habitable rooms the whole thing needs to be properly designed to meet building regulations, particularly with regards to escape from fire.

If you are making valley soakers can you turn the 12" wide lead sideways to make them as wide as you like or would they be too short top to bottom?

Yes indeed but WTO rules don't mean you MUST charge any particular tariff so in many cases we don't currently charge a tariff (perhaps because we don't make those products here). If we go slapping the same tariff on everybody its going to mess up a lot of stable trading relationships. Borris has already said he plans to scrap tariffs to "limit economic damage". As a member of the EU we also agreed to accept a quota of products from outside the EU. On these products there is zero tariff until the quote has been exceeded then a tariff applies. I believe we have already agreed to continue to accept "our share" after Brexit. This agreement was made with the WTO not the EU.

Currently if we can prove they have been through another EU country we can send them back to that country. We loose that right after Brexit.

Under WTO rules if we put a tariff on EU goods we must put the same tariff on all other countries.

Construction timber shortage.. mostly due to the pandemic and demand elsewhere.. https://www.theconstructionindex.co.uk/news/view/timber-industry-warns-of-continuing-shortages

The Guardian: Brexit stockpiling causing 10-mile tailbacks in Calais... https://www.theguardian.com/politics/2020/dec/12/brexit-stockpiling-causing-10-mile-tailbacks-calais "The delays in crossing the Channel are causing acute problems in the UK. Honda and Jaguar have had to halt production temporarily because of parts shortages, and it emerged on Friday that Ikea had been besieged by complaints because of what it called “operational challenges” as shipments of its flatpack furniture are held up at clogged ports."

Good idea. If you do that they might fit the opening ?

In China they have a shortage of glass to make solar panels.. https://theenergymix.com/2020/11/11/chinas-solar-surge-leads-to-glass-shortage/ "With glass supplies running short and prices correspondingly spiking, Chinese solar manufacturers are appealing to Beijing to approve new glass factories—an industry that hit the brakes in 2018 when the country banned further expansion due to overcapacity concerns."