Mum trying to buy the right output boiler...please help!

[ChrisR]

BUT if you use a lot of hot water, and you need to reheat the store quicly, and it's a modern cylinder with a coil capable of transferring 25kW into the water, a (say) 12kW boiler wouldn't be ideal! If the weather were freezing and you had 4 high flow long showers on the trot, you'd be cold and run out of HW.


I know some of the official calculators say to allow 2kW for the HW. Moi thinks they are silly, so there.

 

[Agile]

I think the official think is that the cylinder will be sized to allow for the short term demand and the hot water is timed to reheat before the heating comes on.

The best rule of thumb is 50li plus 50 li per person for up to five people ( 300 li ).

My friend who used to teach HVAC could not remember the volume to use but vaguely though it was 37 li or 45 li per person. But all teachers are teaching outdated data and not accepting the trend for higher flow rate showers.

Tony