LOFT TANK FLOAT VALVE

[RONCHAM]

This is a bit pedantic but should be dead easy to answer! I've bought a new float valve for my loft tank - it didn't come with any plastic washers. One of the two fixing nuts has a raised shoulder on one side (approx. 2mm deep, 3mm wide) around the perimeter of its thread and will screw on either way round - what's this for, is it the inner or outer nut, which way round does it go, and do I need to use any washers??
Thanks in advance.

 

[seco services]

if the hole in the tank is large enough for the lip to sit in you can use it to centralise the float valve if not turn it round so both flat edges tighten to the tank.

have you any plastic washers on the old one ?
sometimes they'll have a metal plate aswell.

 

[RONCHAM]

That was quick! I have got washers if necessary (I suppose in theory water should never reach this level?). Old valve is a similar Part 2 type but has plastic nuts. Loft tank is plastic rectangular and there is no metal reinforcing plate. All DIY books I've seen show flat nuts used with washers but I thought there must be a reason for shoulder on one nut and also a reason for not supplying 1p washers.

 

[seco services]

if you have the washers then you might aswell use them.

 

[RONCHAM]

I did warn you I'm pedantic but thanks anyway!! There must be a reason Screwfix don't supply plastic washers and I doubt it's to save money. And there must be a reason one of the nuts is distinctly different (could be to centralise as you suggested).

 

[david17uk]

Yep as already mentioned above, it's just a centralising nut

You don't really need the washers, which is why screwfix don't supply them. (water shouldn't be at that level like you say)