hot water going cold Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[wimiu012uk]

I have a woster 30i combi boiler and while running hot water for a bath the hot water runs hot and then it runs cold for a while approx 1min and then runs hot again.
Also while using the shower the same happens, this happens even when there is no other demand on the hot water system.
Anyone got any ideas as to why this is happening ?

[htg engineer]

Possibly a fault on HW sensor - or a restriction/blockage in the boiler. If the flames extinguish then the boiler thinks the water is hot enough - when the sensors cool the flames will come back on - so either a faulty sensor telling the boiler it's hot Or the boiler is retaining the heat for too long.


htg

[wimiu012uk]

Thanks for that, will watch next time used to see if flame extinguishes while delivering hot water.

[eggers]

what is the water flow like? is it alot less the before?
does the water become very cloudy?
does the boiler make any kettling noises?