aSense Ventostat 2,000ppm CO2 + RH/T

aSense Ventostat 2,000ppm CO2 + RH/T
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  • SE-0111

  • SE-0115

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Browse more CO2 Monitor or additional Senseair products.


  • 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.

Click here to download the UIP software for aSense.


  • aSense: 0-2,000ppm CO2, temp, 4-20mA or 0-10VDC outputs
  • aSense -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 option
  • Cost-efficient RS485 or LonWorksTM local network communication options
  • Internal 2-channel logger as option
  • Meets ISO 12039 Standard for NDIR detection of CO2


  • 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

CO2 Monitor Data Sheet

CO2 Sensor User Manual

CO2 Sensor SE-0111 Installation Manual

CO2 Meter SE-0115 Installation Manual