Butteryfly Valve

[allwet]

I have a 4" Butterfly that leaks on a sch 80 pvc line for a aquarium on a salt water system. How can I replace it under pressure?

 

[EdStainless]

Freeze the line to plug it and then replace the valve. I have seen comcercial services that use liquid nitrogen to do this.

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Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[mshimko]

Freeze a PVC line? Won't this present a high risk of cracking the PVC?

 

[metengr]

I would agree with mshimko - do NOT use a freeze plug on PVC material. Can you use a bladder or rubber plug on the inlet end of the piping?