On 04/03/2021 23:05, Osprey wrote:
I am going to have to change out my boiler.
I had my whole house heating design done by underfloor heating company.

They sized boiler at 28kW ... (so currently have 30kW boiler)
Think it prudent to check sizing before I order replacement.

I know there are a plethora of €˜rad sizing programs, anybody able to recommend a good one (Stelrad, Castrads etc)

That would be pretty basic approach ... anybody aware of something that looks at whole house.


There are two things to decide first
1/. how much power you need to keep the house warm at the coldest
outside temp and wind you are likely to encounter
2/. How fast you need the place to warm up.

I sized my boiler at 1/. and forgot 2/.
This winter it was on 20 hours out of 24...

Basically an oversized boiler won't hurt - but an undersized one will
struggle

Fit the biggest that will physically fit


--
€œThose who can make you believe absurdities, can make you commit
atrocities.€�

€• Voltaire, Questions sur les Miracles Ã* M. Claparede, Professeur de
Théologie Ã* Genève, par un Proposant: Ou Extrait de Diverses Lettres de
M. de Voltaire