Header tank mould.....

[Mikomotor]

Hi,

Over last few years, I've had various work done to flush CH system / unblock pipes and it's been working fine for over a year now.

The other day, I had reason to check the header tank and was surprised to see not just murkier water than I'd seen in the past, but also a kind of rust coloured 'skin' all round the inside of the tank at water level or just under, probably protruding about 2" into tank. In some areas it seemed quite thick.

Just unsure if I should be concerned and / or whether any action is needed given, as mentioned above, that everything seems to be working fine?

Cheers,
Mike.

 

[Bahco]

Sound like rust .

Has your system been filled with inhibitor?

Might be best to flush out and add some Fernox or Sentinel inhibitor.

 

[JohnD]

also, bale out the F&E first and sponge out all the mud into a bucket. You don't want it washing down into your rads.

A tight-fitting cover will keep dust and wildlife out of the tank.

an insulating jacket will stop it being too warm in summer as well as too cold in winter

AFAIK the anti-corrosion chemicals still contain biocides to prevent fungal growths in the water. Get a good brand like Sentinel or Fernox.

 

[bengasman]

What exactly was done when the system was flushed? Your description sounds like more than a year’s worth of corrosion

 

[Mikomotor]

What exactly was done when the system was flushed? Your description sounds like more than a year’s worth of corrosion

....thanks for your help, everyone.

Bahco / John D - all noted.

Bengasman - I hired the kit and flushed each rad independently as per the instructions. Whenever I've had to empty / re-fill system, I've always added an inhibitor. Last time would have been April (rad off for wallpapering). So, as you say, the state of the header tank really surprised me!

Anyway, I'll clear it all out and hope for the best cheers.
Mike