JEH

I know HeatGeek intend their mini-store to be used with ASHPs but like @JohnMo I'd be very interested in using one to replace my old vented cylinder and gravity fed hot water. I have a new system boiler (Vitodens 100W) but an old cylinder, and I think the mini-store has a load of advantages - not least avoiding the G3 mandatory inspections every year? As I see it, the mini-store is not much different to another radiator zone. Adam at HeatGeek did a test to see if his ASHP could keep a shower going with this tank and it was pretty good but a gas boiler would have no trouble doing that. It would be more efficient to keep a smaller amount of hot water at a temperature close to what we need for a shower - with the boiler condensing at all times when reheating it. There would be less heat loss from a smaller, cooler body of water than a conventional 250L tank at 65°. No chance of Legionella. No immersion heater required, so I can stuff the airing cupboard with insulation that would normally trip the usual thermal cutout. No scorching hot water left in pipes from the tank every time a tap is used. And potable pressurised hot water. I can't quite get my head around the whole thing but I reckon a mini-store could effectively turn any system boiler into something like a more efficient and capable combi with a giant preheat capacity? Would HeatGeek consider installing such a thing and what would it involve?