stop tap orientation

[Dave24]

Why won't a stop tap work if it is fitted with the arrow pointing in the wrong direction?

 

[seco services]

where would you post it then ?
maybe the painting/decorating
****s

 

[blondini]

I doubt that all stopcocks are the same design but in the type I'm thinking of the washer and the part that holds the washer aren't lifted of the seat by the spindle turning, they are lifted by water flow from the mains side. This doesn't work very well in reverse. Also think about which side of the valve the spindle gland is. If you fit it the wrong way round you won't be able to shut off water pressure to the spindle gland if it ever needs attention. .

 

[AlanE]

Why won't a stop tap work if it is fitted with the arrow pointing in the wrong direction?

Because they normally have loose jumpers in them and rely on the incomming water pressure to open them.

Fit it the wrong way round and in all probability the incomming mains pressure will hold the valve closed even if the tap is unwound to open it.

 

[Dave24]

I doubt that all stopcocks are the same design but in the type I'm thinking of the washer and the part that holds the washer aren't lifted of the seat by the spindle turning, they are lifted by water flow from the mains side. This doesn't work very well in reverse. Also think about which side of the valve the spindle gland is. If you fit it the wrong way round you won't be able to shut off water pressure to the spindle gland if it ever needs attention. .

Thanks, Blondini and Alan E. This poses another question: What is the purpose of the loose jumper?