Old panel radiator output

[mr magnolia]

I've an old 70's looking but possibly more modern panel radiator (you know, the ones that every empty house has in them, with vertical corrugations and top and bottom rectangular sections) with a convector fin on the back.

Its 600 by 800 mm (hence may be more modren than 70s?)

question is, what is its likely output?  I've got charts and stuff to calculate new radiator outputs, but I've got one of these old radiators in each of two bathrooms that the calcs would suggest should be different sizes.

They aren't and we have no quarrel with the heat given out in either space.  I just want to replace with new of the same output as existing.

Any steps for a hint gratefully received.

[tonycollinet]

I would just replace with the same size, and fit a stat valve.

Output will probably be higher - but the stat valve will control the temperature, ensuring that it only outputs the necessary heat.

[mr magnolia]

thanks - but I'm instructed to replace with a 'designer' radiator that is just a big tube - so I can't just get the same size and downrate it.

[mrcharly-YHT]

It will be similar to a single-panel modern cheapy of the same dimensions. The wattage of these is quoted on most plumbing store websites.

see here for a list http://www.plumbworld.co.uk/400mm-high-central-heating-2000-0000