Honeywell CRIR M1
A commercial single-channel NDIR carbon dioxide sensor from Honeywell for HVAC, indoor air quality, demand-controlled ventilation and OEM systems.
Key Specifications
Product Positioning
CRIR M1 is positioned as a compact commercial CO₂ sensing platform for ventilation and indoor-air applications where an embedded NDIR measurement module is required.
Official Resources
Specifications on this page are based on current Honeywell manufacturer documentation. Verify the latest datasheet and user guide before integration or purchasing decisions.
View Honeywell CRIR Official PageAirAlign is an independent informational resource and is not affiliated with Honeywell. Manufacturer documentation remains authoritative.
Honeywell CRIR M1 — commercial NDIR and baseline calibration — engineering selection and model documentation
The published manufacturer values below are bounded to their orderable range, test conditions and actual interface, not general guarantees about every relative in the same sensor family.
| Parameter | Manufacturer evidence | Engineering boundary |
|---|---|---|
| Official sensing principle | Single-chamber NDIR CO₂ with filtered optical detector | Measures real carbon dioxide; reference to automatic baseline is an algorithm, not second optical wavelength. |
| Full range | Standard 400–2,000 ppm and up to 10,000 ppm extended digitally | Extended readout is not necessarily the standard-grade calibrated output accuracy band. |
| M1 accuracy | ±(40 ppm +3% of reading) maker grade | At 1,000 ppm the stated nominal expression means ±70 ppm. |
| E1 comparison | E1 is rated ±(50 ppm +5% of reading), not M1 accuracy | Product ordering must distinguish commercial M1 from economical E1. |
| Data link | UART with Modbus-framed protocol; ~4-second measurement cycle | UART protocol does not imply a built-in electrically isolated RS485 interface. |
| Power / response | 4.5–5.5V supply; up to 300mA peak and ~30mA mean; T90 <120s M1 | Controller regulator and buffer need adequate transient capacity. |
| Calibration policy | Automatic Baseline Correction adjusts minimum observed CO₂ to 400 ppm on configured interval | Do not use unchanged ABC assumption in CO₂-enriched agriculture or permanently sealed occupancy. |
| Data sheet currency | Honeywell’s M1 sheet revised/listed February 2026 | Verify purchased revision before legal building monitoring claims. |
System integration and calibration
CRIR M1 is meant for demand-controlled ventilation and embedded building monitors where a proper installation sees fresh-air background CO₂ regularly. For continuous cultivation and occupied 24/7 rooms the ABC baseline can be false and must be disabled or calibrated only when the exact OEM instructions allow it. Tie UART reading-ready/error states to BAS fault alarms, confirm 5V emission current peaks, and separate true data from warmup readings. The M1 accuracy grade is not interchangeable with the E1’s more economical grade.
Source and exact-order documentation: Original manufacturer catalogue, page and/or technical data sheet. Any version- or test-bound claim must be checked against the supplied production label before procurement.
AirAlign model-specific technical editorial update · 25 October 2026. These OEM values are not independently calibrated, certified, or evidence of active supplier stock.