CO2 Check Valve

[fencer]

I don't think there is a special check valve. The reason for the check valve is to stop water from wrecking your soleniod. Mine looks like a simple diaphram...actually looks like an aquarium pump check valve. If you really want to get fancy you can buy a spring loaded check valve for 20 bucks or so. If you do, make sure it can lift off with a couple pounds of pressure( even 1 psi )

[christyf5]

Would this work?

http://oceanaquatics.com/store/produ...lve---Airline/

[fencer]

Mine looks very similiar

[fkshiu]

Brass check valves are a lot more reliable. That's the type recommended for CO2 applications. You can get them at Princess Auto, welding supply stores and hydraulic suppliers.

[Tom R]

Originally Posted by christyf5

Would this work?

http://oceanaquatics.com/store/produ...lve---Airline/

This is the one I am using and I have never had a problem.

Tom R

[Delphinus]

I wouldn't use a brass check valve in a saltwater application.

Dennerle makes a CO2 check valve made of plastic. It doesn't seem to be listed on the Ocean Aquatics website but that's where I got mine. Call Wendell and ask for one.

It looks like this:
http://www.aquacave.com/dennerle-hig...alve-1581.html

[fencer]

I am not sure why that( the Dennerle) should be called a CO2 check valve. In other words how is it different.

[Delphinus]

Don't ask me how it works but it only works for CO2. It's the weirdest thing.

The above shown check valves are OK but I've used them in the past and have had to replace them after 6 to 12 months because they stopped working. The Dennerle I've used now for 4 years continuously and is still working, and appears to be all plastic so no worries about corrosion.

And yeah seriously it only seems to work for CO2, although maybe it's just a question of needing to build up enough pressure in the line (I run my CO2 regulator around 20psi).

[fkshiu]

I think it is a pressure thing. The ones designed for co2 are industrial grade too which would be more reliable than the hobby grade plastic ones you usually find at the LFS. Reeeeeeeeeaaaaaaallly bad things can happen if check valves fail in an industrial setting.

[fencer]

A check valve for a 20 psi application should not have more than 2 psi lift value. You want to open the valve easily but you want it slam shut easily too. and seat properly. Maybe the Dennerle is all teflon(including the spring). But really any type of check valve should work