W
willingnotable
Hi guys, Over the last few months I noticed that the hot water temperature in the shower has been fluctuating from very hot to stone cold every few minutes. Thought it was the thermostatic shower control but decided to check the boiler first. Boiler pressure is 1.5bar, mains cold water supply and pressure is good and constant. So, I ran the kitchen hot tap at full flow and measured the temperature. The boiler clicks on and water heats up to 53c, then boiler cuts out and temperature drops to 41c before boiler clicks back on and heats up again. This cycle continues all the time the tap is on. I set the HW temp dial on the boiler to min - same temp range happened. Set it to max and the boiler heats water to 65c for a couple of minutes then cuts out and down to 41c we go again. I did the same test at bathroom taps with same result. Questions:- 1) Is this normal combi boiler behaviour? 2) If not is this a common problem with a common solution? 3) Can this be fixed by the relevant component (whatever it is) being replaced or is it new boiler time 
Any help and advice appreciated, thanks.
Any help and advice appreciated, thanks.