CO2 Meters & Monitors
Carbon dioxide instruments for indoor air quality checks, greenhouse enrichment control and confined-space gas safety — all built around true NDIR sensors rather than the cheaper estimate sensors found in many low-cost monitors. Ecotao can also supply single-gas, CO2-only models where temperature, humidity or other gases aren't needed.
Browse all CO2 meters at the Ecotao StoreWhich CO2 instrument fits your application?
Six instruments, each suited to a different job. If you're not sure where to start, match your application to the list below.
Spot-checking a room or office
Handheld meter with a live display and alarm for walking room to room.
Long-term environmental records
Leave it running for months and download a full history afterwards.
Greenhouse & grow room CO2 enrichment
Automatically switches a solenoid or fan to hold a target CO2 level.
Smart, connected monitoring
WiFi readings plus PM2.5, TVOC and humidity, with app-based control.
Confined-space & industrial gas safety
Multi-gas detection with alarms, built for tanks, manholes and plant rooms.
CO2 only, no other parameters
A dedicated single-gas CO2 instrument, with no temperature, humidity or multi-gas readings to manage.
Shop CO2 meters & monitors
All six instruments below are in the Ecotao Store. Check the linked product page for current stock and lead time.
S653 CO2, Humidity & Temperature Logger
Long-term environmental logger with a dual-wavelength NDIR sensor and roughly 6 months of battery life on two lithium cells.
Best for: unattended long-term monitoring in archives, greenhouses, server rooms or storage areas where you want a complete CO2, RH and temperature history to review later.
- CO2 range0–5,000 ppm
- CO2 accuracy±3% F.S.
- Temp range−30°C to +70°C
- Memory43,000 records
- Battery life~6 months
C512 CO2, Humidity & Temperature Meter
Professional handheld meter with backlight, audible alarm, Max/Min/STEL/TWA readout and a wide CO2 range, supplied with a carry case.
Best for: walking room to room with a handheld meter for IAQ audits, HVAC commissioning checks or classroom and office ventilation assessments.
- CO2 range0–30,000 ppm
- CO2 accuracy±(75ppm+3%) to 5,000ppm
- Temp range0°C to +50°C
- Memory32,000 records
- Power9V alkaline, ~10hrs
AZ-7530 CO2 Monitor & Controller
Switches a solenoid, CO2 generator or ventilation fan on and off at set thresholds, with a 4.5m external probe and day/night auto-detection for grow spaces.
Best for: automated CO2 enrichment in grow tents, greenhouses and hydroponic rooms, holding a target ppm level without anyone watching a gauge.
- CO2 range0–5,000 ppm
- Sensor2-channel low-drift NDIR
- Probe cable4.5m external
- Control outputZone & centre-value switching
PT02 Smart Air Quality Monitor
Wall-mountable monitor tracking CO2, TVOC, PM2.5, PM1.0, PM10 and humidity at once, with a Tuya smart plug for app-based automation over WiFi.
Best for: continuous smart-building or smart-home monitoring with automatic ventilation, purifier or humidifier control via WiFi.
- TracksCO2, TVOC, PM2.5/1.0/10, RH
- SensorNDIR (CO2 channel)
- ConnectivityWiFi 2.4GHz + RS-485
- Display16.5cm LCD, dimmable
- PowerDC 12V/2A
K-600N Multi Gas Detector
Diffusion-sampling safety detector covering CO, EX, H2S, O2, CO2 and SO2 in one waterproof, dust-proof, explosion-protected body.
Best for: portable pre-entry gas checks in confined spaces such as tanks, manholes and plant rooms, carried in by the technician.
- CO2 range0–5%VOL (50,000ppm)
- Gases detectedCO, EX, H2S, O2, CO2, SO2
- AlarmsSound, light, vibration, display
- CalibrationUp to 5-point
- InterfaceUSB Type-C
K-600M Multi Gas Detector with Pump
Built-in sampling pump tests CO, EX, H2S, O2, CO2 and NO2 remotely before entry, with GPS, TF-card logging and Bluetooth printing.
Best for: testing air from a distance, such as lowering the probe into a manhole or tank before anyone enters, with logged records for safety audits.
- CO2 range0–5%VOL (50,000ppm)
- Gases detectedCO, EX, H2S, O2, CO2, NO2
- Sample flow300–800ml/min, adjustable
- Logging10,000 records, CSV export
- RatingIP65, Ex ib IIC T3 Gb
Compare all six instruments at a glance
Scroll sideways on smaller screens to see every column.
| Model | Type | CO2 range | Other parameters | Memory / output | Power | Best for |
|---|---|---|---|---|---|---|
| S653 | USB data logger | 0–5,000ppm | Temp, RH | 43,000 records, USB software | 2×3.6V lithium, ~6mo | Long-term environmental records |
| C512 | Handheld meter | 0–30,000ppm | Temp, RH, alarm | 32,000 records, USB software | 9V alkaline, ~10hrs | Room-to-room spot checks |
| AZ-7530 | Controller | 0–5,000ppm | Day/night auto-detect | On-screen chart, Max/Min | Mains-powered | Greenhouse CO2 enrichment |
| PT02 | Smart IoT monitor | Tracked (range n/a) | TVOC, PM2.5/1.0/10, RH | WiFi app + RS-485 relay | DC 12V/2A mains adapter | Connected, automated monitoring |
| K-600N | Multi-gas detector | 0–5%VOL (50,000ppm) | CO, EX, H2S, O2, SO2 | On-device alarms, USB-C | Rechargeable, IP65 | Confined-space safety checks |
| K-600M | Multi-gas detector + pump | 0–5%VOL (50,000ppm) | CO, EX, H2S, O2, NO2 | 10,000 records, CSV, Bluetooth print | 4000mAh rechargeable, IP65 | Remote sampling before entry |
Frequently asked questions
What's a good CO2 level indoors?
Outdoor air is typically around 420ppm. Indoor levels under about 800ppm generally indicate good ventilation, while readings climbing past 1,000–1,500ppm are a common sign that a room needs more fresh air. These are general guideline figures rather than a legal limit, and they vary by standard and by country.
What's the difference between an NDIR CO2 sensor and a cheaper estimate sensor?
NDIR (non-dispersive infrared) sensors measure CO2 directly by how much infrared light it absorbs, which is accurate and stable over years of use. Cheaper eCO2 sensors estimate CO2 indirectly from other gases (VOCs) and drift more, so they're fine for a rough indicator but not for compliance, research or greenhouse dosing. Every meter on this page uses a true NDIR sensor.
Which CO2 meter suits a greenhouse or grow room?
The AZ-7530 is built for this specifically: it switches a CO2 solenoid or ventilation fan on and off at set thresholds, with day/night auto-detection so CO2 isn't wasted when plants aren't photosynthesising. The S653 logger is a good complement if you also want a long-term CO2 record for the same space.
Can a CO2 meter double as a gas safety detector for confined spaces?
Not the indoor air quality meters, but the K-600N and K-600M are purpose-built for this: 6-in-1 detectors that monitor CO2 alongside O2, CO, H2S and other hazardous gases, with audible, visual and vibration alarms. The K-600M adds a sampling pump to test air from a distance, such as a manhole or tank, before anyone enters.
Do CO2 data loggers need special software to read the data?
The S653 and C512 both connect over USB and come with PC software for downloading and analysing logged data, no separate purchase needed. The PT02 smart monitor instead connects over WiFi to the Tuya app, and the K-600 series can export logs to CSV or print directly to a Bluetooth printer.
How accurate are CO2 meters at high concentrations?
It depends on the sensor's calibrated range. The S653 logger is most accurate up to 5,000ppm, the C512 meter is rated to 30,000ppm, and the K-600 series gas detectors extend to 5%VOL (50,000ppm) for industrial and confined-space use, where CO2 can reach levels far beyond typical indoor air quality readings.