Robertshaw J10-821

Robertshaw J10-821 is a 24/120V SPST horizontal wall mount humidistat designed to deliver precise humidity control. This unit operates over a 20–80% relative humidity range, helping protect wood, fabrics, electronics, and moisture-sensitive equipment while improving comfort and indoor air quality. With dual-voltage compatibility, it fits a wide range of HVAC systems, delivering consistent performance in both residential and commercial environments. Built for durability, the J10-821 offers reliable, maintenance-free operation and straightforward installation in new or retrofit projects.

• 24/120V AC dual-voltage operation
• SPST (single-pole) switching for simple control
• Horizontal wall mount design for unobtrusive installation
• Humidity range 20–80% relative humidity for stable climate control
• Ideal for HVAC systems and environmental regulation
• Durable construction for long service life