The water pressure in my house is great even with the main valve, gate valve, opened just half a turn. Is it OK to keep valve at just half a turn or should it be opened all the way?

thanks.

I'd keep it fully open. Why would you want to not keep it fully open?

Just wondering. Guy who replaced shower faucet turned water main valve off and only turned it back on a half turn, saying pressure was so good why turn it on all the way. I wasn't sure if this was a good idea or not.

NOT a good idea to throttle a gate valve

excessive turbulence / velocity through valve WILL (eventually) erode and/or 'wire draw' the valve seat and gate

only globe and 'most' ball valves can/should be 'throttled'


hj; please don't start with needle valves, etc.

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

IMO globe and gate valves when opened should be opened completely to "backseat" the valve stem. There may be some time that you would regulate the water flow with a globe or ball valve during actual use. Gate valves are always normally completely open OR completely closed.

Thanks guys. Really appreciate your answers.



Edited 1 times.

not all valves are machined to actually 'backseat'
there needs to be an actual machined seat (or insert) in the valve body AND a specially machined 'plug' on the stem itself:

the reason for backseating a valve is to allow repacking while valve is OPEN
this is a good 'trick' when servicing hi-press steam @ 250 degree F !
(would y'all like pics of my scars?)


alternate backseating:



much more comfortable

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638



Edited 1 times.

He just didn't want to turn it all the way one because it would have taken 30 seconds more to do it, and if his repair did not go right, he would have had to turn it off again. Having it half open does not change the "static pressure" but if you use a lot of water at one time, it will affect the "dynamic pressure" and volume.

The reason for using globe/stop valves is because they CAN safely be throttled. Ball and gate valves can be damaged by turbulence if they are partially closed.

For the reliable operation of the Industrial Gate Valve [anixusa.com] over a long period, several challenges are associated with the pipeline valve's operating and maintenance conditions. A variety of lubricants, the properties, and characteristics of which must be adapted to the operating media and operating conditions, can help prevent problems. Some elements of valves can be made of plastics or elastomers, so when selecting lubricants for valves, their compatibility with these materials should be taken into account.



Edited 2 times.