My household hot water is supplied by a combi-boiler. The boiler is supplied from the rising main. In this cold weather, I'm finding it a bit uncomfortable to rinse my mouth after cleaning my teeth with the water from the cold tap in the bathroom sink due to the temperature. Is it safe to use the hot water tap supplied from the combi-boiler for the purpose?
I've no intention of making tea, filling a kettle or something just as daft from the hot water supply but surely a cupful of warm water from the tap wouldn't do any harm. I well remember the old stories of what people used to find in their hot water storage tanks years ago but there's no prolonged storage involved in a combi-boiler and it is sealed after all. Would it be OK to do this?
Of course that's fine! I've been drinking water from the bathroom tap (fed from a traditional covered tank in the loft) for over 40 years and I'm still alive!
With a Combi, the cold feed is taken from the mains, just the same as any cold tap in the house.
It's the same water. It just flows through a "heat exchanger" where water destined for taps is indirectly heated by the circulating water in the boiler.
In short, you're just drinking tap water, and it's not "radiator" water either ;o)