Torn diverter diaphragm on a Worcester Bosch 24CDi

[Andy7]

The diverter valve on my Worcester Bosch 24CDi has been replaced, but the hot water failed after just a week.

On inspection, the rim of the diaphragm is torn.
The diapragm was fitted the right way round, springs in all the right places and appears to have been seated centrally due to nicely concentric tears!

I've got a spare, and it's pretty straightforward to get it all apart and back again (though I can see why engineers hate that job!).

Wierdly, if I try popping the diaphragm in the WRONG way round, there's a lip that slips nicely into a groove in the diverter valve cap. It almost looks like there should be a big o-ring in the groove in the cap but I've not seen it in any documentation.

Scratching my head....

Could the cap have just been tightened too much? I had to grunt a bit to get some of the screws undone.

I'm a bit reluctant to fit my spare one in case this one tears too.

 

[AfterburN003]

Is it possible it WAS fitted the weong way around? The Vokera diverter valve diaphragms fit into a groove an the divertor cap.

 

[Andy7]

The springs should be facing into the cap shouldn't they? (Away from the valve mech)

Plus the whole movement just feels more natural that way around.