Radiator sizing (again) - are these sizes reasonable

imrreh · Aug 26, 2016

Hello all,

So I'm looking to sort out the central heating, I've done some calculation using a calculator at bestheating website and it has given me the following figures

[TABLE="class: grid, width: 500"]
[TR]
[TD]room[/TD]
[TD]Height[/TD]
[TD]Length[/TD]
[TD]Width[/TD]
[TD]Window Area[/TD]
[TD]BTU[/TD]
[TD]Watts[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]Bedroom1[/TD]
[TD]2.32[/TD]
[TD]2.63[/TD]
[TD]2.44[/TD]
[TD]1.44[/TD]
[TD]1666[/TD]
[TD]487[/TD]
[TD]2 outer walls[/TD]
[/TR]
[TR]
[TD]Bedroom2[/TD]
[TD]2.32[/TD]
[TD]3.45[/TD]
[TD]2.98[/TD]
[TD]2[/TD]
[TD]1329[/TD]
[TD]389[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]Bedroom3[/TD]
[TD]2.32[/TD]
[TD]3.81[/TD]
[TD]3.6[/TD]
[TD]1.96[/TD]
[TD]1555[/TD]
[TD]455[/TD]
[TD][/TD]
[/TR]
[/TABLE]

So the first surprising thing was that the smaller room (bedroom1) requires a larger ouput rad, I can understand that there are 2 outer walls but does that really make such a difference? The current rad that is fitted is the smallest one out of all the bedroom and the room heats up reasonably well.

For bedrooms 2 and 3 I could use a radiator that is 400high x 700mm wide but that may look a bit odd as the windows are around 2m wide. So would it be ok to put wider rads in and use a TRV to control the temp?

Thanks

Chalked · Aug 26, 2016

Radiator calculations are based on heat loss. Not just the size of the room. So 2 outside walls makes a big difference.
Download the Mr combi app. It seems the most accurate to me.

AlexGas · Aug 26, 2016

imrreh said:
Hello all,

So I'm looking to sort out the central heating, I've done some calculation using a calculator at bestheating website and it has given me the following figures

[TABLE="class: grid, width: 500"]
[TR]
[TD]room[/TD]
[TD]Height[/TD]
[TD]Length[/TD]
[TD]Width[/TD]
[TD]Window Area[/TD]
[TD]BTU[/TD]
[TD]Watts[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]Bedroom1[/TD]
[TD]2.32[/TD]
[TD]2.63[/TD]
[TD]2.44[/TD]
[TD]1.44[/TD]
[TD]1666[/TD]
[TD]487[/TD]
[TD]2 outer walls[/TD]
[/TR]
[TR]
[TD]Bedroom2[/TD]
[TD]2.32[/TD]
[TD]3.45[/TD]
[TD]2.98[/TD]
[TD]2[/TD]
[TD]1329[/TD]
[TD]389[/TD]
[TD][/TD]
[/TR]
[TR]
[TD]Bedroom3[/TD]
[TD]2.32[/TD]
[TD]3.81[/TD]
[TD]3.6[/TD]
[TD]1.96[/TD]
[TD]1555[/TD]
[TD]455[/TD]
[TD][/TD]
[/TR]
[/TABLE]

So the first surprising thing was that the smaller room (bedroom1) requires a larger ouput rad, I can understand that there are 2 outer walls but does that really make such a difference? The current rad that is fitted is the smallest one out of all the bedroom and the room heats up reasonably well.

For bedrooms 2 and 3 I could use a radiator that is 400high x 700mm wide but that may look a bit odd as the windows are around 2m wide. So would it be ok to put wider rads in and use a TRV to control the temp?

Thanks