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White wall-mounted air quality sensor, 3.5625 inches wide

SIEMENS

SIEMENS QPA2000 air quality sensor wall mount 3.5625inW thermostat

SKU CH-8WEJ-KB88G

Wall-mount air quality sensor measures CO₂ with ±50 ppm + 2 % accuracy and outputs 0-10 V DC, 0-5 V DC or 4-20 mA on 24 V AC power

  • Product typeLearning Thermostats
  • Product colorWhite
  • Measures CO2 within ±50 ppm + 2% of reading for precise air monitoring
  • Operates on 24 V AC ±20% for flexible building power compatibility
  • Outputs 0–10 V DC, 0–5 V DC and 4–20 mA to suit diverse control systems
  • Functions from –31 °F to 113 °F for reliable performance in extreme environments
  • Communicates via BACnet IP for direct integration with building automation networks

Siemens QPA2000 air quality sensor

The Siemens QPA2000 is a wall-mounted air quality sensor designed for building automation systems. It measures gas concentration and provides CO2 accuracy within +/-50 ppm plus 2 percent of measured value. The unit operates on 24V AC power with a 20 percent tolerance and outputs 0 to 10V DC, 0 to 5V DC, or 4 to 20 mA signals. It communicates via BACnet IP protocol for integration.

Check power and protocol compatibility

Verify that your system supplies 24V AC within the specified tolerance before installation. Confirm that your building automation controller supports BACnet IP communication for data integration. The sensor has no display, so readings must be accessed through the connected automation platform. Ensure the wall mounting location suits the polyethylene housing and white color.

Suits automated CO2 monitoring without local readout

This sensor suits facilities managers adding CO2 monitoring to existing BACnet IP networks where no local display is required. It is not for users who need an on-device screen to view air quality values directly at the unit. Installers without 24V AC infrastructure or a different communication protocol should look at other options.

How it compares

Measured against everything we stock in Thermostats & Thermostat Accessories, at today’s prices. Recalculated every night.

Price $222.99
Pricier than about 86% of the 286 comparable items (median $78.49).

Specifications

Product
Brand nameSIEMENS
Product typeLearning Thermostats
Product colorWhite

Questions about this item

What comes with the SIEMENS QPA2000 sensor and do I need a separate power supply?

The sensor requires a 24V AC supply with a tolerance of plus or minus 20 percent. No display is included and the housing is white polyethylene.

Which output signal should I select for my building automation system?

The unit provides three selectable outputs: 0 to 10V DC, 0 to 5V DC, or 4 to 20 mA. Choose the one that matches your controller input.

How accurate is the CO2 reading once the sensor is installed in a room?

CO2 accuracy is rated at plus or minus 50 ppm plus 2 percent of the measured value across the operating range.

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