Setting Up a CO2-Injected Aquarium
CO2 Tank
CO2 Regulator
Solenoid Valve
Metering Valve

CO2 & the Planted Aquarium

Solenoid Valve

This (the black thing on the right with the wires coming out) is the solenoid valve that turns the CO2 on and off. solenoid valveIt is controlled by the pH meter/controller. On the left you can see the metering valve ("needle valve") that is used to fine-tune the bubble count.

Manufacturer: Snap-Tite/Allied, Valve Division, Erie, PA 16506
Part number: V273X-9
Orifice: 0.250 inch
Voltage: 12 volts DC
Watts: 11
PSI: 5

Note that this valve is rated for only 5 pounds per square inch. My understanding is that most regulators work best at 15 PSI or more. This valve occasionally sticks at that pressure. (That's 3 times its rated working pressue, so it's not surprising.) If I had it to do over, I would have gotten a different valve with a higher pressure rating. This one has worked fine for years at about 12 PSI, however. I got it at a boat supplier and was told that people use them to turn the propane supply on and off.

The valve consumes 11 watts when it's turned on. That's quite a bit, and it gets too hot to touch at the base. It is drilled and tapped at its base, and I'm sure that if it was mounted on a metal base which acted as a heat sink, it would stay cooler.

11 watts at 12 volts requires almost one amp of current (11 watts / 12 volts = 0.92 amps). I run it off an old "wall wart" type power supply, but it's a big one that's rated for 1.5 amps. You can't run a valve like this off a tiny little power supply.

I can't find this valve listed anywhere anymore, so I assume that it's no longer being manufactured. (I bought it in 1999.)