Belimo’s Broadband Refrigerant Monitor: One Calibration Gas, Verified Accuracy

Many refrigerant leak detection monitors are gas-specific, which means they must be calibrated to the exact refrigerant being measured. This can add complexity during commissioning and service as refrigerant types vary by application. For technicians, that means needing separate calibration gas bottles for each refrigerant, which can be a hassle.

Belimo’s 22G21-5C broadband refrigerant gas monitor was developed to simplify the calibration burden without compromising performance. In the field, there is sometimes a perception that broadband refrigerant sensors sacrifice accuracy for flexibility. To address that concern, the broadband sensing element used in the recently released Belimo refrigerant gas monitor underwent benchmark testing for accuracy to verify performance across all selectable refrigerants.

Why Broadband Matters

With Belimo’s broadband refrigerant sensing approach, the 22G21-5C refrigerant gas monitor can be calibrated to one gas (R134a) and then configured in the field to accurately measure any refrigerant in the monitor’s selection list. This simplifies commissioning and ongoing service because installers only need one refrigerant calibration gas bottle (R134a) and are covered, even when the target refrigerant varies by jobsite.

Benchmark Testing

For the benchmark testing, the 22G21-5C was calibrated to R134a and then evaluated for accuracy while detecting the other refrigerants available in the selection list. The example below shows performance when calibrated to R134a but programmed to detect R1234ze, evaluated across the benchmark sequence (0–2000 ppm), with accuracy points at 100, 200, 500, 1000, and 2000 ppm. The testing tracked accuracy through repeat runs using the same sensor, and also tested a second sensor, confirming consistency between different units.

Summary And Field Benefits

For technicians, the 22G21-5C’s simplified calibration procedure is a big advantage. It allows the gas monitor to accurately measure any of the selectable refrigerants, while requiring only R134a for calibration. This eliminates the need to transport separate calibration gas bottles for each refrigerant across different jobs.

Field-selectable refrigerants include R11, R22, R23, R32, R125, R134a (default), R404A, R407A, R407C, R407F, R410A, R448A, R449A, R452A, R454B, R455A, R507, R513A, R1233zd, R1234yf, and R1234ze.

Bottom Line

The 22G21-5C is designed to simplify commissioning and service by allowing installers to calibrate to one gas (R134a) and then configure the monitor to measure any other selectable refrigerant, reducing the need to manage multiple calibration gases in the field. With benchmark testing verifying broadband sensor accuracy, technicians can move forward with confidence that simplified calibration does not come at the expense of performance.