Time to keep central htg restorer in system

[MrSludge]

I have a 16 year old system with almost no circulation.

There are 13 rads and last week-end I added 2 lts of Fernox Heavy Duty Central Htg Restorer after draining down the system. How long should I leave this in for before another draining down? The circulation has improved a little but all of the downstairs rads and a couple of upstairs are not getting warm. Boiler shuts down fairly quickly after coming on presumably because the circulation is poor.

Pump was replaced 3 weeks ago and is working.

 

[oilman]

You could try leaving it in for ever, but if there's no flow in a pipe it will never clear it. The options are: a) get it powerflushed, b) hire a powerflusher and do it yourself (you need an acid descaler), c) remove each radiator in turn and flush them through with a hose, and hope the pipes are not too bad, though you can connec a hose onto the pipes, but if you have a blockage you will subject the system to mains water pressure which is NOT a good idea.

The boiler cuts out because the heat is not being removed as you say, but there is no easy fix for a scaled up system, if chemical treatment doesn't work, it has to be mechanical, and if that doesn't workor is not possible, it's replacement.

 

[ChrisR]

Agree with oilman. You might try closing the "working" rads to force the medicine throughthe cold ones.

I have used the mains many times to clear things out, but now I have a power flusher I wouldn't be without it. There's info on the gas-news site about how to do it. Hiore a mchine - £50 or so a day.

 

[MrSludge]

[/quote]There's info on the gas-news site about how to do it. Hiore a mchine - £50 or so a day.

Sorry can you give me the reference of the gas-news site as I'm not familiar with this?

 

[ChrisR]

It comes up on the first page of a Google search!

http://www.gas-news.co.uk/

Look in Features, number 9

 

[MrSludge]

Thank you for that. Not sure I have the confidence to go for this on my own. I realise BG probably charge a lot for doing this. What's a reasonable sort of amount to pay for this and how do I find a suitable person? I live in Nuneaton.

As an update to the rads, the downstairs ones have draincocks because we have solid floor. Last night, I isolated 2 of the downstairs rads, bled them a couple of times, refilled and hot water came through. But when the system came on this morning, they didn't warm up again. Why is this?

 

[oilman]

Cost for powerflush £200 to £400. To find a suitable person, do some research first read this . There are probably other places as well. The idea is so you can ask pointed questions and understand what should be done. When you understand the process you might just do it yourself of course.

If the rads don't work it sounds like air has got into the system. Do you have any automatic air vents in the loft? If you don't know what one of these is, type "automatic air vents" into your browser search and look around.