Surrey / Warix flanges how to tell the difference????

[Tony Mason]

Does any on know how to establish whether an existing hot water cylinder is fitted with a Warix or a Surrey flange.

I have always had air in the shower water and note that these flanges have different shower outlet positions, the Surrey, at the side and the Warix at the top. I wonder if the plumber we used connected it wrongly and its sucking air from the top of the cylinder.

Any help greatly appreciated

 

[ChrisR]

shower outlets... the Surrey, at the side and the Warix at the top.

Those are the right way round.
To distinguish the fittings, the Warix has a flat hex top with a gasket under it, allowing the body below to be rotated before tightening.

The original HW outlet from the cylinder would have probably gone straight off to the side, which is why the Surrey is silly - and the Warix was invented - I suppose.

Hw temp should be below about 65 to prevent cavitation.

And it's still possible to suck hard enough with a pump bring air in from the vent to the bottom of the dip tube. STRICTLY as a trial only, try the shower with the vent covered - by someone's thumb, say.

If that's the problem, increase the diameter of the CW feed to the HW cylinder; 28mm is usually big enough, but not always.

 

[Tony Mason]

Many thanks ChrisR, I came to the same conclusion and have 28mm on order.
Tony