White Metal Flakes from central heating

[Deleted member 15730]

Hi all,

Today I had one of my boilers replaced, it was in an extended part of the house where the pipe work is buried in the concrete floor.

My GSR sent the following email :-

We did boiler today, I have enclosed these picture !
Filled up , but the rads didn't get very hot , there was a circulation problem ! Even though it was flushed
We kept filling system to 3 bar then opened magna clean and loads of white metal flakes came out !!!!!! They where blocking the return from rads .
I don't no why they are white ! Usually brown or black sludge !! Don't know what type of pipe is under floor

Anyway , I think we got most out, and the rest will be court by the magna clean ! The old boiler was full of them so not surprising the valve was stuck !

I think it will be a case of returning in three weeks to remove magna clean and cleaning out again !

Should I be concerned about a potential problem with the buried pipes ? Or is this something that GSRs come across from time to time and so not a major issue as long as the magna filter does its job.....

Thank you for comments/advice

 

[Masood]

Never seen white flakes! I wonder if the pipework is plastic or MLCP that starting to break up? Or maybe it's flakes of limescale? Are you in a hard water area?

 

[Deleted member 15730]

Yes it is a hard water area......the boiler has needed a lot of pressure topping up (ideal logic plus hex problems back in 2009/10) and i guess a lot of the original inhibitor will have been lost not sure if that explains the flakes though........

 

[Masood]

Yes it is a hard water area......the boiler has needed a lot of pressure topping up (ideal logic plus hex problems back in 2009/10) and i guess a lot of the original inhibitor will have been lost not sure if that explains the flakes though........

Generally, repeatedly topping up with fresh oxygenated water will lead to rusty orange or black magnetite deposits. Do you know what pipe material was used in the extension?

 

[Deleted member 15730]

Unfortunately I don't know what type of pipe was buried.....the extended part is a self contained annex with its own boiler and heating circuit, this was built new back in 2010.

 

[jtsplumbing]

Could be scale get a sample analysed, you could have major problems going on under the floor.

 

[Deleted member 15730]

Here are the pictures the gsr sent me......

 

[Masood]

It's not anywhere near as white as I'd imagined LOL!

That looks like normal metallic sludge - if the inhibitor was lost and lots of fresh water introduced that would be the expected result. The odd whitish flake does look like limescale to me.

You can have water samples analysed quite cheaply by companies like Adey and Fernox amongst others, if it will put your mind at rest.

I find it odd that the system is so dirty after being flushed, though. Not casting aspersions on your GSR's competence but a thorough powerflush would have removed that. How exactly did he flush? A mains flush? Or just run it hot with some cleanser then drain it down and refill? Both are valid methods so he didn't do anything wrong if that's what he did, but they are better suited to less dirty systems.

 

[Deleted member 15730]

No idea how he flushed it but he will check the magna filter again in 3 weeks and see where we go from there......thank you for suggestions.....

 

[Stigster]

Do you have aluminium radiators on the system? I ask because I noticed when getting rid of a load of old aluminium radiators that had been stored for a while, bone dry, that they all had a lot of white metallic flakes a bit like those in them. I could pour out a small handful from each rad. I can't quite work out why there was so much in there. I haven't noticed the same with steel panel rads.

 

[armourer]

I would be more worried about the engineers grasp of English and why he is filling to 3 bar?