On 2020-09-30 15:38:13 +0000, Mike Clarke said:

On 30/09/2020 14:59, John Smith wrote:

Don't install one that is overated - our house has 16 rads/hot water
cylinder but a 24kw boiler is OK.

Unless it supplies a shower and it's a combi boiler and you want a good
flow of hot water.

I'm talking about a system boiler heating an unvented cylinder. In our
three story house the pressure is good enough for a very good shower on
the top floor.

Anyway just had the engineer in and he couldn't fix our old Vaillant.
He didn't have both PCBs on the van but the minimum cost to fix would
be about £300-£350 assuming one board would fix it and if both boards
are implicated that's about £500.

So I've asked him for quotes on a new 28kw (his suggestion) Vaillant
and Ideal, which he says he can fit on Friday or Monday.

At least i didn't have to pay him tonight as no fix no fee.