Whole‑House Renovation: Need Real‑World Advice on ASHP + Fan Coils + MVHR Integration

[JohnMo]

1 hour ago, NetTechie said:

5kW or so does seem low to me

That's because everyone is brain washed by plumbers wanting to install 30kW+ boilers.

 

1 hour ago, NetTechie said:

Total heat loss for room 272, 18W/m2

Doesn't that far out. MCS start doing 2 or 3 ach which soon racks up the heat loss.

 

Your calculations assumes the room above is also heated, which is fine if it is. And should be with ASHP anyway.