Green crust on heating pipe joints

[wx05]

Opened the heat interface unit (I think that’s what it’s called) to read my heating meter, and noticed there’s mainly green (and some white) crusts on pipe joints. Some of it flakes off with just a light brush, but does not come off completely.

Is it something to worry about?

[Kelvin]

It’s copper oxidation (the reason the statue of Liberty is green) happens when the copper is exposed to oxygen and water.  It depends how bad it is. Show us a picture. 

Edited December 19, 2022 by Kelvin

[wx05]

[wx05]

[wx05]

[wx05]

I’m in a new build that was only completed 3 years ago. So this is max 3 years accumulation / damages.

Can I just clean it off? Or the pipes need changing?

[Kelvin]

 Nothing to worry about. Sometimes you might get some water weep and this happens which can self seal, or the plumber left some flux on the pipe (picture two) When to be concerned is when you have a thicker line of it running down a pipe as that means there has been a leak. 

Edited December 19, 2022 by Kelvin

[wx05]

That's a relief.

Shall monitor it from time to time.

Many thanks!

[Nickfromwales]

Yup, flux residue ( likely they used PowerFlux or Laco ) from acidic "self-cleaning" fluxes. The others are leaks which look to have sealed themselves as @Kelvin said.

Clean all these joints up so you can be sure they've cured, but this is typically what you see under a combi boiler where it's leaked a little but then sealed itself up, eg very minor weeping joints.