StillSmart

As per my new post, the pressure reducing valve does nothing other than reducing pressure.

Any flush or tap or heating still affects the flow.

Science.

Try this thread.

viewtopic.php?f=12&t=3065&p=31369&hilit=Gate+valve#p31369

Surely there must be something in a plumbers tool box that achieves this?

Find a plumber and ask is one way....

Any reputable plumber would have a Gate valve skidding around the back of his van.
A needle valve may be more specialist.

Robert.

I use a washing machine valve which works a treat. It's essentially a ball valve. We're talking about defeating fluctuations in water pressure here. Although after a run last night this is no longer a worry for me.