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CAP PPM-4 CO2 Controller






CAP’s PPM-4 is a safe, easy-to-operate CO2 controller that accurately controls the carbon dioxide levels in your growing environment. The controller features two pieces, an electrically safe 120v wall-plug in and a wall-mounted infrared sensor connected together by a 10-foot power cord. The PPM-4 comes factory-calibrated and programmed with an optimal CO2 maximum control set point of 1450 PPM, when levels drop below 1400 PPM the plug-in controller will power the CO2 source until it reaches the optimal point. Reading PPM levels is quick and easy with the 3-LED interface featured on the wall-mounted controller.

Only 4 left in stock

SKU: ENV-CAP-PPM4 Categories: , , Tag:
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CAP PPM-4 CO2 Controller

C.A.P. offers a full range of equipment for growing enthusiasts. The PPM-4 is the simplest, safest, and most affordable CO2 controller available today from any manufacturer. Perfect for controlling LP or natural gas generators with PPM accuracy.


  • The PPM-4 is a two-piece controller that includes a wall-mounted infrared sensor with a 10 ft. cord and a plug-in pass-through controller/power supply.
  • The plug-in control is designed to be electrically safe.
  • Designed specifically to control the carbon dioxide level in your grow environment with PPM accuracy and is easy to use out of the box due to its easy-to-read 3 LED interfaces.
  • Switching set point factory set to 1450 PPM with 50 PPM hysteresis/dead band.
  • Calibration couldn’t be easier. Simply step outside and press a button.
  • The PPM-4 is easily mated to any 120-volt valve or CO2 Generator with a simple plug-in device.


  • Operating principle: Single-beam Non-Dispersive Infrared (NDIR) with a 5” optical path length
  • Recommended calibration interval: 1 to 3 years
  • Measurement range: 0 – 5000 PPM CO2
  • Operating voltages: 120 volts to plug in controller
  • Warm-up time: 1 Minute
  • Maximum amperage: 10 amps @ 120 volts
  • Maximum drift per year: +/- 15 PPM
  • Operating temperature range: 0-50’ C, 32 to 120 ̊F
  • Accuracy @ 77 ̊F: +/- 50 PPM
  • Operating humidity range: 0-99% RH (non-condensing)
  • Operating life expectancy: 15 years typical


Weight 2 lbs
Dimensions 13.5 × 7 × 3 in


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