Hi just wondered if anybody can point me in the right direction, central heating wont come on, if you press the diverter valve in so it hits the micro switches it works but if you let go it turns off, I have taken diverter valve apart cleaned and fit new diaphragm but still wont stop on.

Nozza, May 2018

It isn't the diverter, it'll be the servo valve not returning to its rest position, those little tubes will point you to the servo.
The most likely cause of it not returning will be a leaking water valve through the stuffing box, this 'gums up' the push rod that operates the servo when the domestic water is used.

New stuffing box/water valve & clean the push rod (in the bracket that the servo sits on), Bob's your mothers brother

Carefree, June 2019