This CO₂ Monitor provides real-time measurement of carbon dioxide, temperature and relative humidity, featuring a three-color backlight LCD to indicate CO₂ levels at a glance.

Note: All Tongdy monitors and controls ship direct from the factory. Please allow 10-15 business days for shipping and handling.

It can optionally display 24-hour averages and maximum CO₂ values for more comprehensive tracking. A buzzer alarm can be enabled, disabled, or silenced once triggered for flexible alerting. The device offers optional on/off output to control a ventilator and an RS485 Modbus interface for system integration. It supports multiple power options, including 24VAC/VDC, 100–240VAC or USB/DC adapter, and is designed for wall-mounting (desktop version also available).

• Real-time CO₂ monitoring for accurate indoor air quality management

• NDIR infrared CO₂ sensor with self-calibration for precise and reliable readings

• Long-lasting sensor with over 10-year lifespan

• Monitors temperature and humidity alongside CO₂

• Three-color LCD backlight (Green/Yellow/Red) indicates ventilation levels at a glance

• Buzzer alarm can be enabled or disabled as needed

• Optional 24-hour average and maximum CO₂ display

• Optional relay output to control ventilation systems

• Modbus RS485 communication for system integration

• Touch-button interface for simple operation

• Multiple power options: 24VAC/VDC, 100–240VAC, or USB 5V

• Desktop version also available

Applications

• Schools, offices, hotels, meeting rooms
• Shops, restaurants, hospitals, theaters
• Air ports, train stations, other public places
• Apartments, houses
• All ventilation systems

Specifications

Power supply	100~240VAC or 24VAC/VDC wire connecting USB 5V (>1A for USB adaptor) 24V with an adaptor
Consumption	3.5 W max. ; 2.5 W avg
Gas detected	Carbon Dioxide (CO2)
Sensing element	Non-Dispersive Infrared Detector (NDIR)
Accuracy@25℃(77℉)	±50ppm + 3% of reading
Stability	<2% of FS over life of sensor (15 yr typical)
Calibration interval	ABC Logic Self Calibration Algorithm
CO2 sensor life	15 years
Response Time	<2 minutes for 90% step change
Signal update	Every 2 seconds
Warm up time	<3 minutes (operation)
CO2 measuring range	0～5,000ppm
CO2 Display resolution	1ppm
3-color backlight for CO2 range	Green : <1000ppm Yellow: 1001~1400ppm Red: >1400ppm
LCD Display	Real time CO2, Temp &RH Extra 24h average/max/min CO2 (optional)
Temperature measuring range	-20～60℃(-4～140℉)
Humidity measuring range	0～99%RH
Relay output (optional)	One relay output with rated switching current: 3A, resistance load
Operation conditions	-20~60℃(32~122℉); 0~95%RH, non condensing
Storage conditions	0~50℃(14~140℉), 5~70%RH
Dimensions/ Weight	130mm(H)×85mm(W)×36.5mm(D) / 200g
Housing and IP class	PC/ABS fireproof plastic material, protection class: IP30
Installation	Wall mounting (65mm×65mm or 2”×4”wire box) Desktop version also available
Standard	CE-Approval

Downloads

Wall Mount CO2 Monitor with Temp / RH Datasheet