Simplified Installation: 3/4" NPT threads and the compact PopTop footprint allow for quick retrofits in tight mechanical closets

making it compatible with a wide range of modulating hot/chilled water valves and actuators

Advanced System Diagnostics: Integrated logic helps technicians quickly identify and resolve system lockouts and safety switch trips

Key Benefits for Contractors Broad Operating Range: Temperature range of -40°F to +50°F makes it suitable for various medium and low-temperature R407C systems

this is a brand-specific Lennox replacement part

Resideo L4006A1009 Aquastat Controller 321894-709 Simplified Installation: 3/4" NPT threadsThe Resideo L4006A1009 Aquastat Controller is a professional grade immersion temperature controller designed for precise regulation in hydronic heating systems, storage tanks, and boilers. This high or low limit aquastat utilizes a 3 8" x 2 7 8" copper sensing bulb to monitor liquid temperatures between 100F and 240F. Featuring internal SPST contacts that break on temperature rise, this unit is engineered for reliable safety shut off or cycling