MAMAC Systems HU-921-VDC-7 Humidity Sensor

The MAMAC Systems HU-921-VDC-7 is a high-performance HVAC humidity sensor engineered for demanding commercial environments, including roof-top air handlers, fresh air hoods, and return air ducts. This unit mount transmitter delivers a precise 0-10Vdc output proportionally across a 0-100% relative humidity range, maintaining 3% accuracy between 30% and 70% RH. Designed for long-term stability in 100% condensing environments, it features conformal coated electronics and a proprietary ePTFE filter that shields the bulk polymer capacitive element from salt air and pollutants.

Integrated with a 10,000 Ohm NTC thermistor (Type III), this sensor provides simultaneous temperature monitoring, making it an essential component for economizer control and advanced humidification/dehumidification strategies. The rugged 20% glass-filled polycarbonate enclosure and 1/4-inch quick disconnect terminals ensure a streamlined installation for any technician. Whether you are performing a field replacement or a new OEM installation, the HU-921-VDC-7 provides the reliability required for modern building automation systems.

• All-Polymer Sensing Element: Utilizes a fast-response bulk polymer capacitive sensor for rapid detection of humidity shifts.
• Contaminant Protection: The oleophobic ePTFE filter prevents sensor drift caused by fog, pollutants, and condensation.
• Versatile Power Compatibility: Reliable operation with a supply voltage of 12-40Vdc or 12-35Vac.
• Wide Operating Range: Fully temperature compensated to maintain signal integrity from -30°F to 130°F.
• Industrial Durability: Housed in a UL-95-V-0 rated low-smoke enclosure suitable for plenum applications.

Is this sensor compatible with my existing BAS?
Yes, the 0-10Vdc humidity output and 10K Type III thermistor represent industry-standard signals compatible with most major HVAC controllers.

Can this unit handle high-moisture air streams?
The electronics are specifically moisture-sealed with an acrylic coating to survive 100% condensing humidity without failure.

What are the wiring requirements?
The device features standard 1/4" male quick-disconnect terminals and accepts up to 12 AWG wire for secure connections.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.