when to use Viton or Teflon check valves

[celica]

I have used both Viton and Teflon check valves. The Teflon seem to last longer but don't seal as well under lower pressures. Viton check valves seal better but are prone to break completely in failure. I'm kind of on the fence on which one to use. They are used for the various functions that you see at the car wash. I didn't know what anybody else's experience has been. Both cost almost the same, so cost isn't really an issue. Your thoughts?

 

[MEP001]

I try to use Teflon whenever possible. The ones I use have a Teflon seal that won't come off the poppet. I have noticed as you have that Teflon doesn't always seat 100% under low pressure, but once they've been used under high pressure the Teflon conforms to the seat and they then provide a positive seal. Would it be too much bother to run the Teflon in a high pressure application to break them in before you move them where you need a 100% seal at low pressure?

 

[OurTown]

I try to use Teflon whenever possible. The ones I use have a Teflon seal that won't come off the poppet. I have noticed as you have that Teflon doesn't always seat 100% under low pressure, but once they've been used under high pressure the Teflon conforms to the seat and they then provide a positive seal. Would it be too much bother to run the Teflon in a high pressure application to break them in before you move them where you need a 100% seal at low pressure?

Which ones do you use?

 

[MEP001]

Teflon, but in the self-serve I have no place for check valves that isn't on high pressure.

Fluid Controls CV-100T Stainless Steel Check Valve - 1/4 In FxF , 3500 PSI, 4 GPM, PTFE

This Fluid Controls CV-100T check valve is made with stainless steel and has a PTFE O-Ring with female 1/4" connections. Rated for 4 GPM and 3500 PSI.

www.kleen-ritecorp.com