Radiator sludge and flushing

Hi,

We have gas fired CH here (not a combi) and one big downstairs radiator in the lounge isn’t heating at the bottom (hot at the top). The rest are fine (thirteen in total) but one does require bleeding every 2-3 months. We’ve had no specific radiator work done for the eight years we’ve lived here (new pump, couple of replacement radiators where rooms refurbed) but I’ve no idea about the application of corrosion inhibitor and the boiler hasn’t regularly been serviced. I turned all but this radiator off and set the CH running and it still failed to heat promptly and uniformly so the pump itself seems fit for the system.

By all accounts this is a sludge problem, so beyond agreement of the initial diagnosis is it best to:

1. Get a plumber in to drain down, remove this one rad and give it some irrigation
2. Get a plumber in to chemically flush the system
3. Get a plumber in to power flush the system
4. Move house / something else

I don’t want to get mugged on some unnecessary treatment as it seems like flushing and associated operation has a bit of an aura about it (as well as BG being one to avoid).

Also anyone get any recommendations for this work in Huddersfield (or slightly wider area)?

Have you balanced the system? If not, you might have radiators near the boiler shorting out others further away, so they don’t warm up (they are all wired/plumbed in parallel).

You could try shutting off all the TRVs except the cold rad and seeing if it then heats up?

Footflaps – did you read his post? He’s already isolated that rad and it made no difference.

Why don’t you drain down the system yourself and flush the radiator with a hosepipe.

Then when you let the system refill you can add some inhibitor so you know it’s got some in it.

It’s a very easy job to DIY and needs nothing more than a spanner and a bleed key (and £10 for the inhibitor).

tbh, you don’t even need to drain the whole system if you’re careful – you can turn off the taps on that rad and just slightly undo that radiator at one end until water comes out and drain it into a bowl. I find cutting a coke bottle to the right shape to fit and using it as a funnel helps a lot.

if it was me , id drop the water, remove the rad and take it out side – give it a seeing to with the hose on the drive – possibly even the pressure washer.

Stick it back in , put in some fernox cleaner and run the system to temperature for the prescribed time.

then drain it and refill with inhibitor.

You just reminded me i should empty the magnaclean filter this week pre winter.

How ever if this

is you. Get a plumber to come and give his opinion.

+1 for draining the rad and cleaning it out with a hose in the garden. Lots of YouTube tips on this.

IME a power flush is a total waste of time.

I had this exact problem. Took every radiator out and flushed them all in the garden, then I flushed all the pipes. (Top tip, one of the B&Q hose adaptors from their value range screws into standard 15mm pipework fittings). Flushed every pipe in the system and cleaned the header tank. Refilled with inhibitor.

Made no difference at all. I hope you have more luck.

I had our entire system power flushed and it made a huge difference – couldn’t believe how much of a difference!

It helped that I’ve got a mate who’s a plumber!

DIY it, heres a few tips:

1) Close the valves either side of the rads!!

2) Make a wooden wedge/s out of a bit of softwood floorboard. Use a joiners axe to shape it to valve hole, old valves often leak you can’t tell before hand because the system is sealed, the wooden wedge quickly swells and blocks said leak from valve leaking on to the floor while you are in the back garden flushing the rads!

3) Drain as much out of each rad as necessary to carry and flip (you don’t need to drain all of the water out till you get to the garden), 2 people blocking the valve holes with thumbs then lift and quickly flip no more drips!!

4) Hose out the rad till water runs clear can take a while!

I’ve resurrected 70’s systems that have never been serviced this way, that have then gone to work for over 10+ years.

Have fun 😉

I would prioritise the boiler service to be honest, carbon monoxide is the silent killer.

Make sure you cover the area around the rad VERY well. If any of that sludge gets on your carpet, you’ll struggle to get it out.
And to mtbfix who said power flush is a total waste of time.
You know absolutely nothing pal.
The only time a power flush is a total waste of time is:
a. When you don’t need one.
b. If you do and it’s not done correctly.

You can flush everything with just one radiator off can’t you? I did (I think!) by closing them all off at both ends, then opening them up one at a time with clean water going in one end where the one radiator was off, dirty water then after a few minutes clean water coming out the other end where that one was off. Close that one and open the next. Had to tie up the ball cock in the wee header tank first, then poured a bottle of that stuff and and let it all fill up again. System still works!

thegreatape – Member

You can flush everything with just one radiator off can’t you?
This would be one method of connecting a power flusher, but not knowing how to use it properly and also additional ways to help remove the sludge, (some of which can be almost solid where it’s gathered over the years,) will render your efforts futile.
Please refer to my previous comment.

I did it with a hosepipe from my garden tap. I don’t doubt what you say either, but it got a load of crap out so must have done some good?