Turning valve - pump always off?

[BeijoNJ]

new homeowner, sorry for dumb question.

A YouTube video mentioned that you should ALWAYS turn ur pump off first before moving any valves (like shutting off Main drain and turning to partially skimmer)

Is this true??? Or can I have the pump running and turn the valve? Does it turn easily or a little force? I’m scared to break anything!! Thanks!!!

 

[AK-]

You should “always” turn off.

You don’t want to run damage the pump by running it dry if you close its water supply, you don’t want to burst a pipe or damaging the pump if you close a valve after the pump by over pressure.
It is not just pressure, moving water also has inertia and when it suddenly stops moving you get a water hammer.

Most 3/4-way (aka multi-port) valves will always briefly be in a closed position when changing ports.

If you absolutely know what you are doing AND all your valves are simple valves then you might get away if not turning off the valve. Emphasis on might.

 

[duraleigh]

Yeah, turn the pump off when changing ANY flow.......it's just good practice.