Air admittance valve McAlpine anti-syphon basin trap

[Mutley56]

Hi,

I’ve fitted one on my basin. Do I remove this screw cap and blanking piece completely to set the trap up, or loosely screw the white cap back on.

Thanks for the advice.

Mutley56

 

[blup]

Hi,

I’ve fitted one on my basin. Do I remove this screw cap and blanking piece completely to set the trap up, or loosely screw the white cap back on.

Thanks for the advice.

Mutley56

AFAIK you need both, the white cap secures the blue disc which moves up and down in to seal and release air, which then passes through the white cap so don't tighten hard.

 

[Mutley56]

Thanks blup