Hot water goes cold then hot then a little warm ,now no hot water ,central heating is fine
Thomas
February 2017
ive had this problem.its the filter.a silver box fitted at the back of the boiler.eventualy tracked the problem down,and had it flushed out.it was ok for a couple of weeks,then went again.we then had a new one fitted and that was ok for a couple of months,and has just happened again.so now we will have to find out why this keeps happening.ime 100% sure this is your problem.it looks like the bottom of a burnt sausepan when cleaned out.!.hope this helps.
nigel.
May 2010
sounds like the diverter valve is not operating correctly