AL01 Carrier — Humidifier fault
At a glance
- Severity
- WARNING
- Domain
- air_handling_unit
- Reference standard
- UNI EN 13053, VDI 6022, ASHRAE 62.1
- Product / context
- Sensor fault
What it means
The AHU humidifier is not working correctly. The relative humidity of the treated air does not reach the required setpoint. This can be caused by faults in the humidification section (steam, atomized water, or adiabatic) or its related sensors and actuators.
Probable causes
- Steam humidifier cylinder exhausted (accumulated limescale)
- Water supply solenoid valve stuck or not opening
- Humidity sensor faulty or out of calibration
- Water humidifier nozzles clogged with limescale
- Humidifier control board faulty
- Power supply to humidifier absent
Where to start
Check the condition of the steam production cylinder (if it has excessive limescale, replace it). Check electrical supply to the cylinder. Verify water level in the cylinder. Check the water fill solenoid valve. Measure current draw.
Full guided diagnosis in the app
The diagnostic tree for this fault has 5 guided steps with measurements, checks and resolutions. You'll find it in HVACIQ, one of the five IndexOS apps: free, works offline.
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