It depends for me on how in depth the design is and cost? If it’s a modest sum and a case of “I have looked at your plans and insulation, I suggest X panels, X cylinder and X heat pump” then it’s great, without getting bogged down.
this was my issue on the solar thread. I want my entire set up to be the best possible and work together, but the ‘design’ comes from the salesman and that seems dicey?
I actually have a new oil boiler in storage and a tank, I’m wondering how insane it would be to have air source and solar on my new build but also utilise the oil set up I have in storage?
I had my reservations but didn’t want to void the warranty. Turns out it doesn’t - so it’ll be filled with water and lean
mixed backfilled as usual.
I had it half full 2400 litres, their spec is 1/3 full 1600 litres. Gravel bed, shingle backfill- maybe 16t in all.
Yep sorted now- tried the dry install they recommend and a complete waste of time and materials. Contacted them and they’re fine with a concrete install “It’s just not in the literature because it’s German”.
the tank popped up like a U boat.
Ffs did This at the weekend. A Graf sewage plant- ignore the instructions it CAN be wet installed in concrete. I had an absolute fail with sheet piles and a 5 ton digger.