Metal slivers coming out of all the hot water taps.

[Gazzer]

Hi guys any advice much appreciated. We had a new Baxi 630 combi boiler fitted last July. The last few weeks we have had what we thought was sand residue left in the sinks and bath. Thinking it was the water board doing whatever. Now we realise they are magnetic slivers of metal and only coming out of ALL the hot water taps. Cold completely clear. I have tried flushing all the taps for ages and it makes no difference. The metal slivers are shiny and can be picked up by a magnet. I have contacted our installer who in turn contacted Baxi but they just said it must be the house plumbing because they have a stainless steel exchanger . There are no valves in the house which we have been in for 30 years. I have checked and traced the pipework in the loft and under the floor. No metal valves and all fittings are brass or copper.
Any suggestions?

 

[Ric2013]

Doesn't sound like steel pipe as that would be rust and would be dark brown.

Is the grade of stainless used by Baxi non-magnetic?

 

[Gazzer]

Doesn't sound like steel pipe as that would be rust and would be dark brown.

Is the grade of stainless used by Baxi non-magnetic?

Thank you for your reply.I really don't know. I know that there are different grades of s/s and some have a carbon steel content and only the highest grade used for marine are "pure" s/s.There is definitely no steel pipework in the house. I'm quite disappointed with the way they have reacted. Surely you would think if it is the exchanger they might have received a poor quality batch and in their own interest at least check it.

 

[Chuck]

The Baxi boilers I'm aware of use ANSI 316L stainless steel for their heat exchangers. In its annealed condition this is not ferromagnetic but it can become ferromagnetic after welding or cold working.

It doesn't seem very likely that 'shiny' ferromagnetic particles suddenly start being from 30 year old copper plumbing.

 

[Gazzer]

Thanks for your reply.I don't think so either. Our plumber who fitted it is coming round this week to check out. The cold intake and hot output are very easy to access at the boiler. Supposing the boiler hot water and cold water p/work was disconnected and a flexible pipe was fitted between them completely bypassing the boiler , this would either eliminate or prove the boiler was at fault , wouldn't it ? The boiler does not need to be heating the water for the particles to come out. I've flushed the hot taps for ages with the boiler switched off and still get the metal coming out.

 

[Ric2013]

Supposing the boiler hot water and cold water p/work was disconnected and a flexible pipe was fitted between them completely bypassing the boiler , this would either eliminate or prove the boiler was at fault , wouldn't it ?

Good idea!

 

[Ben-gee]

Yes that should prove it, obviously need to clear what’s in pipes already - but if it’s the boiler responsible, you should run clear after a few minutes.
Maybe pulse it on/off to catch any stubborn bits.

 

[Gazzer]

Okay guys thanks for your replies. When our plumber has checked things out I'll let you know the outcome either way.

 

[cjg]

plate heat exchanger got chromed inside by mistake?

 

[Gazzer]

Okay guys thanks for your replies. When our plumber has checked things out I'll let you know the outcome either way.

It's taken all this time for the water be completely clear. Baxi engineer came out and changed the heat exchanger which did have particles inside but didn't look like it was causing the problem cleaned out the boiler and gave it a clean bill of health. Our plumber came back and completely renewed the hot water outlet pipe. Waited a few days ,no difference . He came back and renewed the cold water inlet. When removing the pipework it was full of scaly "crud" which looked "shiny" when in water. Obviously the culprit. The expansion pipe must have filled up and dried out over time and the central heating water dried out and whatever was in it stuck to the inside and took the best part of a year to start coming off. Both the engineer and plumber said it was normal practice to utilise the C.H. header tank expansion and pump header when changing from a system to a combi. Maybe so. Just giving you guys a heads up if you encounter something similar in the future.