PowerFlush of CH

[futureechos]

Hi All.

My CH/HW hasn't had much love and attention in the last ~10 years, and we've been putting this right as issues arise. The boiler (Worcester Bosch 19/14 cbi I think) failed a few months ago which was fixed with servicing it, and the duo/zone valve was replaced a month ago to fix the lack of CH.

I was shown a build up of black stuff in the surrounding pipework when the valve was changed, the pump is noisy on startup and makes various noises so I've been advised I need to powerflush the system, and I know I need a new pump.

The CH certainly takes a little while to warm up downstairs, which I've been tweaking by closing down the rad values upstairs but clearly not a great way forward, likely more sludge in the pipes.

So powerflush sounds like a good idea, however I'm worried about causing leaks in the existing pipework.. When we replaced the kitchen we found a leaking compression joint that corroded the pipe, the pipe looked galvanised, and this runs behind walls up to the water tank so worried if there is more corrosion there will be a pinhole or perhaps more serious leak.. it's all hidden.

So Q1)
I guess I don't have much of a choice? but should I be worried about causing leaks with a powerflush?

Q2) We have 10 single and 1 double rad, some of which are quite old, a couple with sticking TRV's. Would it be worth replacing the older rads before the powerflushing?

Q3) A quick off guess by the plumber who did the Duo Valve said around £500 for a power flush, for a 11 rad 5 bedroom house is that within reason?

Thanks all for the advice, I'm an enthusiastic amateur but out of my depth here.

Mark

 

[JohnD]

If you are a keen DIYer and can do basic plumbing, you could give it a chemical clean and add a system filter.

It is cheap and easy and will do nothing but good, even if you eventually do need a powerflush.

Are your radiators cold in the middle?

 

[futureechos]

Hi JohnD,

When the system gets going the rads heat up fine, hot all over, but some seem to take long while - since the duo valve was replaced though 1 rad in far opposite corner of the house to boiler seems to not get as hot. no air lock, valve and TRV open full so might be sludge/blockage perhaps moving around?

When I bleed rads it comes out black, and the CH has been drained several times over the years when we've been fixing/moving rads and re-routing pipes. (I can do basic plumbing but time and enthusiasm lacking, especially if I screw it up... means I think I'll leave this to someone who knows what they are doing. Been a few years since I've done any pipework plumbing and lost all confidence to be honest).

 

[ianmcd]

Im a little bit concerned about the pipe that you found leaking, you say it was galvanised this is doubtfull, if you can have a look at this pipe and feel all round it and see if you can feel a seam on the pipe, there is a chance that your system has some truewell pipe on it and if it does you wont be able to use chemicals or a power flush, truewell pipe was used when there was a shortage of Copper but its horrible stuff and if you do have it you will have to replace it

 

[futureechos]

Hi Ian, OK thanks v much, I'll take some pics tonight and see if anyone can advise.

 

[ianmcd]

Hi Ian, OK thanks v much, I'll take some pics tonight and see if anyone can advise.

Yes please do, lots on here very experienced with truewell, not the end of the world if it turns out to be that but will need replacing dont try and flush it if it is that

 

[futureechos]

OK so here's the pic of the pipe that was replaced, down in the kitchen in 2010 (IMG_0045.jpg)

And the existing in the airing cupboard: IMG_1908 and IMG_1909.

thanks for your help!


Mark

 

[Dan Robinson]

That's the stuff.... Yuck.

 

[slapper]

Truewell +1

 

[futureechos]

Damn. . Thanks for the heads up, at least I know what we are up against.


So is the price about right for a power flush?

And replacing rads before is a good idea?

Thanks
Mark

 

[Elkato531]

I think the advice was not to flush.

 

[futureechos]

The plan is to replace that piping before the flush, the system needs flushing as far as I can tell.

Unless there are other ways to address?

 

[ianmcd]

You will have to replace all the truewell before you can flush anything or you will end up with lots of bits like that