Why is an isolating valve supplied with an air valve?
If you’ve ever been quoted an air valve “complete with isolator”, here’s why it’s there, and why those three words don’t quite tell the whole story.
What does the isolating valve do?
It lets you shut off the air valve from the main, so you can inspect, service or replace it without draining the pipeline. Close the isolator, do the work, open it back up.
What type of isolator do I need?
It depends on the size. Smaller air valves can have an integral ball valve built in. Larger ones need a separate butterfly or gate valve fitted underneath.
Is “complete with isolator” enough?
Not quite. We still need to know the air valve type, size, inlet connection, pressure rating and the isolator you want. One recent enquiry for a 100 mm double orifice air valve with isolator needed both the air valve and a suitable lugged butterfly valve to go with it.
Why does it matter on industrial sites?
On sites where shutting off the water isn’t an option, like data centres, hospitals or factories running around the clock, the isolator is what makes routine maintenance possible at all.
Quick tip: check there’s room to reach and operate the isolator once everything is installed, especially in a chamber.
Before you enquire, have ready: air valve type and size, pressure rating, flange standard, medium, and whether you want an integral or separate isolator.
Related reading: Which type of air valve do I need? · Does a butterfly valve need a lever or a gearbox?
Contact us now to see how we can help you!
Contact us by email at sales@gavalves.co.uk or call us on 01484 711983
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