worcester greenstar 24i junior problem

[ledge]

hi i have a Worcester greenstar 24i junior boiler ,cental heatiung working ok and the pressure on boiler is fine ,when I run hot water for a bath the water comes through hot for about 5 to 10 mins then shuts the boiler down and the reset and blue buttons start to flash,only does this when I run hot water,any ideas what is best to change first,also is it best to call Worcester bosch engineer to fix problem.many thanks.

 

[Agile]

Exactly what pattern of flashes on the blue light?

Tony

 

[ledge]

hi tony
the blue light flashes light for 2 seconds goes dim then light and goes off again and then repeats ,hope this makes sense,

 

[bazdaman]

Is the light more on or off (blue one)

 

[ledge]

Hi the blue light is more on than off.

 

[Agile]

hi tony
the blue light flashes light for 2 seconds goes dim then light and goes off again and then repeats ,hope this makes sense,

We need to know how many flashes!

And if they are slow and fast flashes!

Tony

 

[ledge]

hi ,the blue light comes on for 2 seconds goes slightly dim but not off for approx. 1 second then goes back to full blue light then goes off and repeats the sequence,hope this makes sense.

 

[Agile]

Right at last! Its 2 sec on and 1 sec off!

That indicates a heat exchanger or flue overheat.

Like most Worcester fault codes there can be several causes which makes fault finding more demanding.

It can also be the PCB too!

In my limited experience of this fault code it has usually been the overheat stat being out of calibration. BUT it can also be caused by dirt in the system too.

So as usual my advice is to get a competent engineer who is not phased by the complexities of fault finding on these models!

Tony