Milky coloured hot water from combi?

[Gareth]

I had a combination boiler (Baxi/Potterton) installed about 6 weeks ago. The boiler seems to be working okay in terms of providing central heating and hot water.

The problem is that the hot water provided by the boiler has a milky white colour - to the extent that when the kitchen sink is filled with hot water the water is completely white. I thought, initially, that the problem was perhaps down to flux in the system or alternatively to limescale (I live in a very hard water area). But I think something else is probably wrong. The problem seems to be less apparent when the bath is filled with hot water and more apparent when water is drawn from a sink.

Has anyone come across this before?

Gareth

Is this anything to be worried about?

[Gordon Henderson]

Fill a glass. Let it stand for 5 minutes. Does it clear? (from the bottom up?)

If so, it's probably air getting into the system - some taps do this by design and there are little widgets you can fit onto them to do this, because some people like it.

If it's clears, it's probably nothing to wory about!

Or you might have a leak thats sucking air in somewhere...

Gordon

[mark_yh]

If it clears as described above then this is normal for a combi boiler, and just the result of naturally dissolved air in the mains water coming out of solurion as the water heats up. In a tank system any bubbles have time to fully come out as the water sits for a long time at high temp. With a combi, there's not enough time so you end up with milky hot water....

[Gareth]

Thanks Gordon and Mark. Yes, the glass of water clears within a couple of minutes - from the bottom up. After a while the air bubbles are visible as tiny individual bubbles. Thanks!

Gareth

[John Rumm]

You may find it worst at low flow rates (i.e. with just a trickle of water) - up the flow and you ought to get less.

[Dave Fawthrop]

|I had a combination boiler (Baxi/Potterton) installed about 6 weeks ago. The |boiler seems to be working okay in terms of providing central heating and |hot water. | |The problem is that the hot water provided by the boiler has a milky white |colour - to the extent that when the kitchen sink is filled with hot water |the water is completely white. I thought, initially, that the problem was |perhaps down to flux in the system or alternatively to limescale (I live in |a very hard water area). But I think something else is probably wrong. The |problem seems to be less apparent when the bath is filled with hot water and |more apparent when water is drawn from a sink.

It is dissolved air which is coming out of the water. It even happens with our very *soft* water. I have discussed this with an Environmental Health Officer and he confirmed that it was OK to use this milky water straight out of the tap, to be incorporated into food, to serve to the public. Because the water has not been stored in a perhaps mucky tank.

[Owain]

If you label it as "oxygen enriched water" you can charge more for it :-)

Owain

[Adrian C]

Fish would thrive in the stuff (if they could see where they were going!)

[sponix]

Mine does exactly the same! Seems it's air in the water.

sponix

[Steve Walker]

At that temperature, they're going on a plate....

[Adrian C]

Doh! At least they won't see that one coming (like me...)

[Christian McArdle]

Yes, it happens with any unvented system, including heat banks (which are unvented on the DHW side).

Christian.