** Note: CO2Meter will be closed Monday May 29th in observance of the Memorial Day holiday. Operations will reopen at 8:30 am et on Tuesday May 30th. Orders placed after 1:00 am et Friday May 26th will ship on May 30th. Happy Memorial Day!! **

aSense Ventostat 2,000ppm CO2 + RH/T

aSense Ventostat 2,000ppm CO2 + RH/T - CO2 Meter
Regular price $849.00

POs or wholesale quantity discounts click here

  • LEED Projects & Credits
  • Green building design
  • Green building certification
  • CO2-Controlled Fan or Alarm

The aSense is an all-digital, low-cost CO2 and temperature transmitter for installation in a building’s climate zone. It measures both carbon dioxide concentration and temperature in real-time, and returns the values to the HVAC system.

The aSense is a key component in green building projects and is designed to maximize LEED credits for both LEED design retrofits and new LEED buildings. Studies show that demand-controlled HVAC systems using CO2 can save up to 50% of energy costs as well as improving comfort for the occupants.

For installations that need to drive a fan, alarm, horn, flasher, etc, the aSense -RL includes a normally open relay programmed to close at 1,000ppm.


  • SE-0115: 0-2,000ppm CO2, temp, 4-20mA or 0-10VDC outputs
  • SE-0111 -Disp RL: includes above + LCD Display, 1 Amp relay


  • State-of-the-art Non-Dispersive Infra-Red (NDIR) technology to measure CO2
  • Cost-optimized for connection to LEED, DCV or HVAC systems
  • Contributes to lower energy costs when it is applied in a Demand Control Ventilation (DCV) strategy
  • Internal automatic self-diagnostics
  • Maintenance interval > 5 years
  • Serial communication port for connection to a PC or a GSM module
  • 2 analog outputs as standard (V/mA)
  • Relay output as an option
  • Cost-efficient RS485 or LonWorksTM local network communication options
  • Internal 2-channel logger as an option
  • Meets ISO 12039 Standard for NDIR detection of CO2


This device will NOT meet requirements for CO2 safety monitoring which requires a Fixed/Wall mounted, hard-wired alarm per the NBIC, NFPA, or IFC regulations. Refer to our CO2 Safety Products page for devices that meet your needs.

Call us at (877) 678-4259 toll-free or email us to speak with our technical sales team about purchasing the correct device.


  • Operating Principle: Non-dispersive infrared (NDIR) with Automatic Baseline Correction
  • Response Time (T1/e): 2 min. diffusion time
  • Accuracy: ± 1% of measurement range ± 5 % of measured value
  • Pressure Dependence: +1.58% reading per kPa deviation from normal pressure, 100 kPa
  • Annual Zero Drift: < ± 0.3 % of measurement range
  • Measurement ranges: 0 – 2,000 ppm (standard)
  • Temperature Range: -20 to +60 C


  • Power Input: 24 VAC/VDC ± 20%, 50-60 Hz (half-wave rectifier input)
  • Power Consumption: < 3 Watts average
  • Wiring Connections: screw terminals, European and US standard J-boxes
  • Dimensions: 120×82×30mm (4.7×3.3×1.2in) HxWxD


  • 2 years manufacturer - See CO2Meter Terms and Conditions. 
  • Data Sheets

  • Manuals

  • Technical Documents

  • Videos

  • Additional Resources

  • Case Studies

Customer Reviews

No reviews yet

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

- Phillip Farrar
Water Plant Superintendent

Read More Reviews...