cast iron radiator clean and reconnect

[chrispy33]

Hi all

Just in the process of reconnecting 2 cast iron radiators to a combi system (approx 18 months old/new pipework etc) and wondering the best way to clean the crud from them.

The radiators look in pretty good condition and i've got them outside and have been flushing them out with a hosepipe. Question is, is this the best or only way to get the muck out? They're bloody heavy as you'd expect so its impossible to give them a good shaking but i've been banging thm with a rubber mallet to try and agitate them etc. Can i leave something soaking in them for a few days, if so what?

Would it also be a good idea to run some cleaner in the system after reconnecting? I'm replacing the copper pipe to them as i don't want to leave a weak link in the chain, also new trv's fitted etc.

Cheers for the help in advance

C

 

[gas4you]

You could fill them with Fernox DS40, but read instructions very carefully first and only use this if you are certain they can stand it.

 

[chrispy33]

Thanks Dave, would this really shift the muck out or do you think plenty of time with the hose would be sufficient. i know this is a kind of 'how longs a piece of string' question, just want to make sure that I'm doing a good job. Also my girlfriend would probably kill me!!

C

 

[gas4you]

Hose and water will clean most 'loose' stuff out. Chemical will eat away at harder stuff. But as DS40 is very powerful only use if you think rads can stand it. Only you are there to ascertain condition of rads

 

[ChrisR]

The waterways are so big I'd have thought it hard to block them completely. As long as water goes through OK it'll get hot, so does a lack of a %age of heat dissipation really matter that much? Compromise if they're old rads.
If you use DS40 or FX-2 do use neutraliser or it'll possibly eat away at the jointing materials.