Blue staining coming from electric shower

[dan_the_plumber]

Hello All.

I've got a quick query concirning a job I'm doing at the moment.

It's an electric shower that had been leaking water down behind the shower unit, through a hole in the tiles and into the wall, which blew the tiles.

I removed the shower, re-tiled and made sure of a good seal where electrical cable comes through wall with grout and silicon.

I then made a really good seal at back of shower with more silocon and ran a beed across top.

The cold feed is not in the wall it is clipped to tiles.

So I pretty sure it's all sealed nicely, however we still have this blue oxide staining occuring on the tiles.

I have only spoken on the phone about it so far, customer recons it's coming from the actual guts of the shower, which in my view is the only place it can be coming from.

I just wondered if anyone else has had this problem?

Is it a specific component of the shower that might cause this?

If not what is this blue oxide caused by?

Any help as usual very much appreciated

Regards....Dan

 

[Paulus]

Hi dan,

The oxide is obviously copper oxide which could be coming from any of the copper components in the shower unit. Once you take the cover off it should be easy to find the source. Most likely it's the copper tank in there if it's an old unit.

 

[dan_the_plumber]

Yes I was thinking i could follow the trail left by the Copper Oxide.

I've done some reading on internet and it seams that what I can expect is a corroded joint or even a pin hole in the pipe.

As it seams to me this may be caused by electrolytic action.


All the earth cables are attached as they should be in the unit.

Dya recon this means there might be a problem with the earth bonding of the shower unit or is it just one of those age things?


The shower has been in for about 4 years


Cheers....Dan

 

[TGor]

Copper oxide is usually red or dark brown .. most green staining is copper carbonate compounds .. Blue colour is copper sulphate .. it may well be that there is some kind of anodic protection in the shower unit which might be causing a reaction .. but without chemical analysis it's hard to say. If its not leaking then you can't do much more.

 

[dan_the_plumber]

Hi TGor

Copper oxide is red/brown is it...ok thanks

Yeah maybe there is some kind of sacrificail onode built in the shower I guess there's no way of knowing without contacting the manafacturer

I'll check pop the cover off and check for leaks....It's obviously coming from somewhere

The customer is happy for me to replace components if needs be but obviously if I can avoid doing that i will

Thanks for the advise

Dan