Thetford C263 CS noise

[pearley]

Our toilet has started making a rattling sound for a few seconds on occasions after the finger is taken off the flush button. Difficult to diagnose as you can't press the button with the cassette removed.

 

The 'wiring diagram' in the manual is next to useless but the parts diagram gives a bit more info. We have the control panel which houses the switch and 3 LEDs, a flush valve and a vacuum breaker. The rattling noise is probably the flush valve and it is relatively easy to replace, although expensive. Not sure where the vacuum breaker is but perhaps if faulty could be holding the valve open. Or maybe the control panel is faulty sending a partial voltage to the valve causing it to chatter.

 

Anyone else had this problem or any thought or is it diagnosis by substitution.

c263cs.pdf

[ditchcrawler]

Vacuum breakers are normally just a vent with maybe a float to close them off, nothing powered