radiator sizes

[Roger Mills]

Yes.

It's not an exact science - don't worry too much! Just imagine the rectangular 2-storey space you would have if you removed the staircase, and regard that as one 'room'. Then treat what's left of the ground floor hall as another 'room' and what's left of the first floor landing as a third room - and add all 3 heat losses together.

I don't remember anything like that when I bought from them - but mine was only a single-panel finned rad. Can you give an example of what you mean by pointing to a particular page on their site?

It stretched my credulity a little!

[Stephen]

Hello again,

I got that slightly wrong. Some web sites have a separate page for singles, doubles, and "one and a half"s but the heating shop just lists them all together by size:

was thinking of another web site, I can't remember which now, but it too listed all rads by size, gave the price for the single and then said "an extra £xx" for the P+, and extra £yy for the double, which wasn't straightforward.

A local merchant is offering "ultraheat" radiators; has anyone heard of them; are they any good?

Thanks again, Stephen.

[Stephen]

If I understood it correctly, they were saying that the "ribs" in the radiator were closer together? If so would it give off more heat either because of an increased surface area or because it holds more water?

I have now been offered an ultraheat 500x1400 quoted at 7743 BTU at dT=50, which also seems higher than the others, though not as high as the Quinn.

So to be safe I will buy a 1600mm length in whatever make is cheapest!

I can't understand how these manufacturers get different results because I thought they had to be tested in standard rooms?

[Roger Mills]

If you increase the surface area, you will increase the heat output (provided you pump more water through it to compensate) - which is why a rad with fins has a higher output (by about 50%) than a rad without.

But fins is fins and I'd expect all rads of the same basic construction to be much of a muchness. Fin spacing will have an effect - so my hunch is that a spread of perhaps 5% would be reasonable but that 15% would be pushing it.

I could be wrong, of course!

[Stephen]

Thanks for your patience in this thread. Sorry it has taken me so long to choose a radiator! It's a good job it's not winter or we would have frozen by now! I'm thinking of getting a Stelrad now because they are

450mm tall rather than 500mm and I think 500mm would be too close to the curtain. What is the recommended space between curtain and radiator?

Thanks again.

[PeterC]

I hope a negative figure, as my curtains tuck down the back of the radiator!

[Clot]

Upstairs, we have sufficient clearance between the top of the rads and the window cills for me to have installed veneered contiboard shelves to deflect the heat into the rooms when the curtains are closed.

Downstairs we have one window where the only solution was to have a curtain of sufficient length to tuck behind the rad.