The shower has a habit of running hot and cold. We are using a combi boiler but no other water taps or washing machine /taps were being used at the time.Water does not go stone cold but reduces from very hot to cool.
most likely thermostatic cartridge going funny, buy them on line or at good merchants for about £45, can also be inbalanced water pressures but more likely the stat, easy to swap
rawplumb
November 2010
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