The hot water goes from hot to cold then hot and the process repeats itself.
i've changed the Thermister but it hasn't made any difference.
If you turn on the hot tap only halfway the hot water is consistence, but as soon as you open fully it goes cold and then the cycle starts again.
the shower is exactly the same
any suggestions
a combi can only put out a set amount of hot water if you turn the tap on too much you exceed the specified flow rate and the water won'be hot (this is most noticeable in winter when the mains cold water is COLD) check the specs for your boiler it should be able to give you an hot shower so long as the shower head doesn't allow more water through it than the boiler can cope with having said all that you may have a problem with the boiler but as you can get hot water i don't think so
brian
January 2011
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