**Please Note: The CO2Meter offices will be closed in observance of the US Thanksgiving holiday beginning at 5:00 pm et. Wednesday, November 24. All operations will reopen Monday, November 29 at 8:30 am et. Orders placed after noon et. November 24 will be fulfilled on November 29. Happy Holiday!**

Day Night CO2 Monitor & Controller for Greenhouses

Day Night CO2 Monitor & Controller for Greenhouses
Regular price $249.00

POs or wholesale quantity discounts click here

The Day/Night CO2 Controller can be used in greenhouses, grow rooms, hydroponics rooms, and other places where elevated carbon dioxide levels are used to maximize plant growth.

  • Accurate CO2 Generator Control
  • Photo Sensor Turns off CO2 at Night
  • Easy Fresh-Air Calibration
The Day/Night CO2 Monitor & Controller lets you set high and low target CO2 levels. Using advanced hysteresis logic, when CO2 levels get too low, power is supplied to a CO2 generator or regulator via the built-in 100-240 VAC 5A piggyback power cord. When the target level is reached, the power is turned off.
In addition, the CO2 Monitor & Controller has a built-in photo sensor that overrides the CO2 control and shuts off the CO2 when it senses darkness. Photosensor control saves dollars and energy by ensuring you’ll only be supplying CO2 during the light cycle when it is needed.

Best of all, the CO2 Monitor & Controller is easy to install and use. Simply mount the unit inside your grow room, (all cables and hardware included), plug it into a standard wall jack, plug in your CO2 generator or regulator and it is ready to maximize your plant growing yields.

See our CO2 Tank Regulator with Solenoid Valve here.

View our CO2Meter RAD-0501E for Greenhouses with European Output.


  • Large digital LCD display clearly indicates the current CO2 level and temperature
  • Easy to read display with all functions set from 3 push buttons
  • Power, upper limit, lower limit and photo sensor verification LEDs
  • Non-UV Emitting LED's - no interference with the grow cycle
  • IP54 Enclosure - cover during cleaning, fertilization, or washdown
  • Default settings: Low Set Point - 800 ppm. High Set Point - 1,500 ppm
  • Measurement Range: 0-10,000ppm
  • NDIR CO2 Sensing Technology
  • Accuracy: ± 70ppm or ± 5% CO2
  • Sensor Response Time: < 2 minutes
  • Operating Temperature: 32° to 122° F
  • Calibration: In-situ with fresh air
  • Sensor Life Expectancy: 15 years
  • Relay: One Relay output, Peak Current < 5A@ 250 VAC, SPST. Normally Open
  • Max Coverage Area: 1,500 sq.ft. with proper air handling 


  • Power: 110VAC Grounded US Plug Only
  • Power Consumption:2 Watts Maximum
  • Piggyback Cable: Peak Current < 5A @ 250 VAC


  • 1 year - See CO2Meter Terms and Conditions.
  • Data Sheets

  • Manuals

  • Technical Documents

  • Videos

  • Additional Resources

Customer Reviews

Based on 15 reviews
MetroCrops, LLC.
great device

perfect for indoor growing - vertical farm

Max Meraner
The plugs...

Surely good devices, problem is I thought I was buying the EU version: unfortunately the price and the looks of the devices are the same and I ended up ordering the US version by mistake. My bad, I admit it, but since the devices are not cheap and I bought three of them, plus the shipping address clearly said "Italy", it would have been nice to get a mail from your customer service checking in if the devices were really the ones that I needed (which is unlikely, having both US plugs instead of EU ones). Fortunately the device itself works on both US and EU voltage, so I'll just have to purchase six extra adaptors of two different kinds...

Paul Nelms

These are great when they work, I have four of them and two were faulty from new. Warranty is a drawn out blame game irrelevant of the fact that they have turned up faulty. Like I said they are great when they work but the quality is ambiguous and the back service is disgraceful.

Stephanie Williams
good value and product

good value and product

Dave Wignall
Fantastic unit

Rock solid performance as one should expect from a greenhouse controller. Have used several in the past and rate them as extremely user friendly and reliable.

"Easy to install, easy to set up, and easy calibration - just what I was looking for."

- Phillip Farrar
Water Plant Superintendent

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