Using old steel radiators

[robandjan]

Hi,

I have the opportunity to obtain 7 steel radiators (free of charge), they have been stored for the last 6 years (indoors) but the inlet and outlet were never sealed. They appear to be OK but I was wondering if anyone could advise me on their suitability for use in a new system I shall be installing soon.

Many thanks in advance

Rob

 

[gas4you]

They could be ok but inefficient in output by todays standards.

How old were they when they were stored?

Give them a good chemical flush first if you decide to use them.

You probably won't get any others to match them visually now either.

 

[chrishutt]

They could be ok but inefficient in output by todays standards.

How? All radiators are 100% efficient in that the energy extracted from the circulating water is 100% put into the space being heated.

Give the rads a good flushing with a hose outside before installing them and then the chemical cleaning mentioned.

 

[gas4you]

If they do not have fins on then then they will need a larger surface area to get the same amount of heat out of them, therefore more water in them so more water for the boiler to heat to acheive the required room temperature.

 

[chrishutt]

That doesn't really alter their efficiency in any significant way, except in terms of wall space required per kW. The amount of water being heated up doesn't make that much difference, especially when combi boilers are usually massively over sized for the heating load. The amount of heat put into the water at one end and the amount given out at the other end will be the same with or without fins.

I suppose heat up time might be a little quicker with lower water content, so reducing the time the heating needs to come on in advance of demand, but by the same token the heating can switch off a little earlier in advance of the end of the demand period with higher water content.

Also radiators without fins radiate more and convect less, and the radiant effect will make the room feel warm more quickly than the convection effect. But I doubt whether any of it makes any difference worth worrying about.