worcester cdi24 hot water not hot enough?

[stee41]

Hi all,

Fan assembly replaced after it siezed, central heating working fine, no thermostat and all appears ok with the boiler but..
The hot water is nearly always warm and rarely hot enough but once every few weeks the water becomes far too hot for a day or so then back to warm again, the temperature control dial on the boiler is on maximum
any ideas guys this has been going on for months now and it is doing my nut in! lol

 

[boilerdoktor]

first thing to check is pull the dhw stat knob out and see if it has snapped in situ!

 

[stee41]

DHW control knob is absolutely fine... filled a bath last night with DHW temp knob on max and didnt need to put cold water in the bath, an hour later I practically scalded myself getting washed, the temp is all over the place at times!! any idea what to check next?

 

[Agile]

The temperature sensor may be intermittently faulty.

But apart from a 24 hr monitor I dont know how you can best monitor it. I would place test leads on the sensor and measure the voltage across it constantly and look at it as the boiler faulted.

Tony