Belimo 22DCM-11 : Active Duct Air Quality Transmitter, CO2 + VOC + Temperature, 0-5V / 0-10V Output, NDIR Dual-Channel CO2, 3 Analog Outputs, NEMA 4X / IP65, 24 VAC/VDC (C + Metric), 5-Year Warranty

What does the 22DCM-11 measure?

This SKU measures CO2, VOC, Temperature. Each measurement has its own dedicated analog output (3 outputs total), so each value can be wired to a separate BAS analog input simultaneously.

What output signals can this provide?

All 3 analog outputs are voltage-only: jumper-selectable between 0-5V and 0-10V per channel, minimum 10 kΩ load resistance. For a 4-20 mA output option, see the universal-output 22DCM-13 variant of this same product.

What is the difference between the 1x and 5x hardware revisions?

The leading digit after 22DCM- indicates the hardware revision. 1x SKUs are the older 2022 revision: they ship with the A-22D-A35 mounting flange and an ø6-8 mm cable gland; no 1/2" NPT conduit adapter is included. 5x SKUs are the newer 2024 revision: they ship with the A-22D-A34 mounting flange and include a 1/2" NPT conduit adapter in the box for direct compliance with US/Canadian/Mexican NFPA conduit installations. Sensing technology and accuracy specifications are identical across both revisions.

How does NDIR dual-channel CO2 sensing work?

NDIR (non-dispersive infrared) measures CO2 by detecting how much infrared light the gas absorbs at a specific wavelength. The 'dual-channel' design uses a second reference wavelength that CO2 does NOT absorb — by comparing the two signals, the sensor automatically corrects for lamp aging, dirt accumulation on the optics, and background gas interference. This is why the sensor is self-calibrating and rated for ±50 ppm/year long-term stability without manual recalibration.

What does VOC measure and what range does it cover?

VOC = Volatile Organic Compounds — gases released by paints, solvents, cleaning products, off-gassing materials, cooking, and combustion. The metal oxide semiconductor sensor measures total VOC (TVOC) from 0-100% relative concentration (equivalent to roughly 0-5000 ppb TVOC). Output scales linearly across the range. VOC is typically monitored as a relative trend rather than a calibrated absolute value — a sudden VOC spike is a meaningful BAS event regardless of the absolute ppb number.

How do I choose between DCK, DCM, and DCV?

DCK = CO2 + VOC + Temperature + CO2/VOC Mix (4 outputs, max IAQ coverage). DCM = CO2 + VOC + Temperature (3 outputs, no mix value). DCV = CO2 + VOC only (2 outputs, no temperature). Choose by which signals your BAS actually uses — there's no benefit to paying for outputs you won't wire. If you need temperature at the same duct location and want to consolidate sensors, DCM or DCK eliminate a separate 22DT install.

Can I use this just for temperature?

Yes, but it's overpriced for that use — if you only need duct temperature, the single-variable 22DT family is significantly cheaper and provides 8 selectable measuring ranges that this combo sensor does not. Use the integrated temp output here only when you also need CO2 and/or VOC at the same location.

Does it need 24V power?

Yes. The 22DCM-11 requires 24 VAC or 24 VDC (19-29 VAC, 15-35 VDC). Power consumption is 4.3 VA AC / 2.3 W DC — higher than single-variable temperature sensors due to the active CO2 NDIR sensing element.

What air velocity does it need to operate?

Operating air flow range is 1-40 ft/s (0.3-12 m/s). The CO2 NDIR cell needs some air movement past the probe to refresh the gas sample for accurate readings. Below 1 ft/s the reading lags actual duct air composition; above 40 ft/s the response stays accurate but probe vibration becomes a long-term wear concern.

Can I configure this sensor with the Belimo Duct Sensor Assistant App?

Yes. The Belimo Duct Sensor Assistant App (iOS / Android) connects to this sensor via the A-22G-A05 Bluetooth dongle for parametrization — adjusting CO2 scaling (2000 / 5000 ppm), output mapping, and (on multi-variable sensors) the CO2/VOC mix ratio. Most installations don't require this — the sensor arrives pre-configured with sensible defaults — but it's available for advanced or non-standard applications. See the Documentation section above for the app brochure.