Heating Advice

I have just had a new combi boiler installed. The hot water in the bathroom sink comes out cloudy and white. Should this happen and is it safe?

The water from combi boilers is heated directly from the mains – so the only time the water is released to the atmosphere is when it comes out of the tap. This means that during heating the calcium bi-carbonate, present in the water, changes to calcium carbonate.

This causes the creation of carbon dioxide which, close up, is seen as millions of bubbles, this is not sediment it’s merely cosmetic and is not harmful. If you run some hot water into a glass and let it cool it will slowly clear. This phenomenon is more apparent in hard water areas and from models with perhaps slower and / or lower flow rates.

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