technicians should use anti-static protection and verify all terminal connections are secure and free of oxidation before powering the system

avoid mounting the actuator below the horizontal plane to prevent moisture from entering the housing

the 93-HDLS utilizes a robust mechanical float-operated mechanism to provide reliable boiler pump control and essential low-water protection

Smith water heater latches

also identified as the SA-12S Indicator

Caleffi ZVR104 Relay 319852-301 technicians should use anti-static protectionThe Caleffi ZVR104 is a professional grade 4 zone valve relay designed for precise control of hydronic heating systems. Serving as a direct HPZC104 replacement, this multi zone controller manages up to four zone valves and features priority zoning functionality, allowing a single zone to be designated for domestic hot water (DHW) production. Engineered with a multi pin selectable priority option, the ZVR104 ensures that space heating loads are