As a veteran HVACR technician, you know that precise environmental monitoring is non-negotiable for system performance. The Johnson Controls D351AA-1 Display Module is a purpose-built digital interface designed specifically for use with System 350 humidity controls, such as the W351 and W351P series. This module provides a continuous 3-digit LCD readout of actual relative humidity (RH), drawing its power and data directly from the parent control via a reliable 5-pin plug-in connector. The D351AA-1 humidity display is engineered for high-accuracy sensing and troubleshooting. By pressing the integrated setpoint button, you can instantly verify the humidity setpoint value, ensuring the system is dialed into the correct parameters. This unit effectively monitors conditions with a 10-90% RH range and includes critical diagnostic indicators: the display signals an out-of-range condition if the setpoint exceeds 95% RH or if the sensor value surpasses 100% RH. Housed in a durable NEMA 1 thermoplastic enclosure, it supports both surface and 35 mm DIN rail mounting, making it a versatile HVACR digital readout module for demanding commercial and industrial applications. Key Benefits for the Contractor: Plug-and-Play Integration: Standard 5-pin connectors provide seamless communication with System 350 modules without additional field wiring. Robust Diagnostic Logic: Quickly identify sensor failures or setpoint errors through built-in out-of-range notifications. Application Versatility: Suitable for permanent installation or as a portable service tool when used with a WHA29A extension cable (up to 50 feet). Durable Construction: Features a high-impact NEMA 1 enclosure designed for professional environments. Common Questions: Can this module display temperature or pressure? No, the D351AA-1 is specifically calibrated for humidity. For temperature or pressure readouts, use the D350 or D352 modules respectively. What power source does this require? It is powered by the 12 VDC supply provided by the W351 Humidity Control module once connected. Is this module compatible with other sensors? It is designed to work with HE-67S3 Series Humidity Transmitters when connected through the W351 controller. 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.
