The Pro Leaf CO₂ Regulator is a brass regulator with a built-in industrial solenoid valve, an adjustable flow meter and an Australian mains plug. It mounts on a standard CO₂ cylinder and controls the rate gas is released into your space — and because the solenoid is switched by mains power, it is the piece that lets a controller run your CO₂ for you rather than you opening a valve by hand.
The missing piece in an automated CO₂ setup
This is the arrangement we run, and it is one of the better-value things you can do with an AC Infinity system. Take a Controller AI+ with the CO₂ + Light Sensor in a sensor port, put a UIS Control Plug on a device port, and plug this regulator into the control plug.
The controller now reads ppm and switches the solenoid to hold your target, all visible in the app on your phone. Better still, it is the same controller running your extraction fan, so it can hold off venting while the CO₂ is doing its job rather than pushing it straight out the duct. A dedicated CO₂ controller does that one task and costs considerably more; this does it inside the system you already own. Both the control plug and this regulator carry Australian plugs, so there are no adapters in the chain.
What you get
A brass-bodied regulator with an oil-less pressure gauge and an adjustable flow meter so you can set the release rate to suit your room size. The solenoid is a heavy-duty industrial valve rather than a hobby part, wired to a 240 V Australian plug and ready to connect. Two plastic cylinder washers and CO₂ dispensing tube are included, and the hose tail suits 4.2 mm internal diameter hose.
Specifications
| Product identification | |
| Brand | Pro Leaf (not an AC Infinity product) |
| Product name | CO₂ Regulator / Solenoid |
| Performance and technical | |
| Flow rate | 0–30 L/min, adjustable |
| Body | Brass |
| Gauge | Oil-less pressure gauge |
| Valve | Heavy-duty industrial solenoid |
| Electrical | 240 V / 50 Hz, Australian plug fitted |
| Hose tail | Suits 4.2 mm internal diameter hose |
| Included | Regulator with flow meter, solenoid valve, CO₂ dispensing tube, two cylinder washers |
| Not included | CO₂ cylinder |
FAQ
How do I automate it?
Plug it into a UIS Control Plug connected to a Controller AI+ running the CO₂ + Light Sensor. The controller switches the plug's power, the plug powers the solenoid, the solenoid opens. It also works on a simple timer or schedule from a Controller 69 Pro or Pro+ if you do not want ppm-based control, though then you are dosing blind.
Does it come with a CO₂ bottle?
No — the cylinder is sourced locally from a gas supplier. Bottles are heavy and are usually supplied on an exchange or hire basis, so buying locally is both cheaper and more practical than shipping one.
Do I need an electrician?
No. It arrives with an Australian plug fitted and goes straight into a socket or a control plug.
What flow rate should I set?
It depends on the volume of your space and how quickly you want to reach target, which is why the meter is adjustable. Start low, watch the ppm reading on your controller, and increase until the room reaches target in a sensible time without overshooting badly. If you do not have a CO₂ reading to watch, that tuning is guesswork — which is the argument for the sensor.
Is CO₂ worth adding to my room?
It pays off once everything else is already right — light intensity at the top of what the plants can use, temperature and VPD steady, feeding not a limiting factor. Enrichment raises the ceiling when nothing else is holding you back; it will not compensate for a room that is short on light. Get a fortnight of climate data first if you are unsure which situation you are in.
Anything to know about running CO₂ safely?
CO₂ displaces air and is heavier than it, so it collects low. Keep enrichment to sealed or well-managed grow spaces rather than rooms people sit in, ventilate before spending time in the space, and shut the cylinder off at the bottle when you are working in there. Ask us if you want the setup checked over before you order.