There is a water stat in the pipe to the left of the heat exchanger which senses the temp of the incoming water. Easy to replace - pay about £20 for it. Beware, it is MAINS water so turn the supply off before you remove stat
Alistair Gilroy
February 2009
hot water thermistor needs replacingh
stu
January 2009
I can answer this question...
How can i fix my Revenheat boiler hot water problem ?