isolation valves arrow

[darren bergin]

normal iso valves (type you turn with screwdriver)
why have they got flow arrow marked on them?
looks physically the same whichever way around
would it affect flow if wrong way around?
thanks

 

[Nige F]

Well, a million site-work monkeys can`t be wrong

 

[darren bergin]

the reason i ask, say if your extending radiator circuit and you want to put some of these iso's in line and you didnt know which was flow and return from boiler
would it make amassivve difference if one was installed wrong way around

radiators would still heat up!!!! shirley

 

[Gasguru]

Never EVER EVER put isolating valves designed for hot and cold domestic service on the heating pipework. Eventually they always leak on the spindle seal.

Only use quality full bore isolators with a seperate compressable gland seal on the spindle.

However you should not require isolating valves just to add a circuit.


The arrow indicates the flow direction. If you install them backwards then once in the off position the water pressure (mains) can force the ball out so it no longer isolates