worcester 24i DHW prob

[Bigred]

Hi, guys, just had a customer on who is having problems with his 24i, a number of repairs already,filling loop, diverter valve,(not by me) tells me that CH only ignites with low flame and that DHW will only work if the CH is on, (when he makes DHW demand no ignition) hasnt been serviced for a couple of years, boiler is a few years old, any ideas before i go to see?

Thanks

 

[SimonJohns]

Diaphragm or micro switch