Combi Boiler Question

[accyis]

Hi. Can anyone explain a query i have with combi boilers?
When running the domestic hot water at a restricted flow rate (mid rate) into a glass it arrives extremely cloudy(It eventually settles down) If i run it off at full flow its fine and clear. I've experienced this with worcester, baxi's etc. Is this common with all combi's?
Can anyone shed any light please?
Thank you

 

[gas4you]

Yes it is quite common for this to happen.

If water clears from bottom upwards it is thousands of little air bubbles. Clearing from top to bottom would be some sort of solid.

 

[accyis]

Thank you. Yes they clear from the bottom upward. I assumed it was air due to the restriction. Could this leave a resisdue at all?

 

[gas4you]

I personally have not known it to.

 

[ChrisR]

The air bubbles are held in solution (like co2 in a bottle of fizzy drink) while the water's at pressure.

If you open the tap full, it drops in pressure at the flow restrictor in the combi, and big bubbles which don't cloud the water, have a chance to form up inside the pipe.
If you open the tap a little, the water is pressurised until it reaches the tap, so the bubbles only form when the water comes through the tap, so they're still there for you to see.

 

[gas4you]

The air bubbles are held in solution (like co2 in a bottle of fizzy drink) while the water's at pressure.

If you open the tap full, it drops in pressure at the flow restrictor in the combi, and big bubbles which don't cloud the water, have a chance to form up inside the pipe.
If you open the tap a little, the water is pressurised until it reaches the tap, so the bubbles only form when the water comes through the tap, so they're still there for you to see.

Thanks Chris always wondered why it happened

 

[accyis]

Ok, thank you for your quick reply. It's never caused me a problem.
Thanks again.