Stone cold radiator - tried just about everything!

[JohnD]

no. 2 and no. 5

and probably some others

//www.diynot.com/forums/viewtopic.php?t=37170

 

[Hooky]

I think we have balanced radiators, turning valves to a minimum nearest the boiler etc. I am also getting conflicting info on whether to have the heating on or off when you bleed the radiators. Can I add more inhibitor as we have added a fair amount of fresh water to the system over the time we have been trying to sort this. We have 19 radiators. Does that have bearing on how much we should add? Would we do this the same way as the sludge stuff and if so do we wait till the sludge stuff has done its stuff and then add it?

 

[JohnD]

if you have 19 radiators you probably need two litres each of X400 (sediment loosener) and X100 (inhibitor). The ratio is a 1% solution. My system holds 85 litres of water and has 9 radiators (some rather large).

Because you drain out the X400 after 4 weeks, washing out the loosened sediment, most people will not top up the inhibitor until the refill.

the chemicals will cost you about £15 per litre bottle each.

If you can do basic DIY plumbing and have signs of sludge, and can afford an extra £100, you can fit a Magnaclean as well. I guarantee you will be amazed and delighted to see how much sediment it captures.

 

[gigz]

I am also getting conflicting info on whether to have the heating on or off when you bleed the radiators.

Turn the heating off while bleeding, start at the furthest lowest rads first, then same upstairs, once full bleed again after a few days (if you have inhibitor in and no leaks you should'nt need to bleed again for a long while)