also identified as the SA-12S Indicator

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

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

the polyester media is designed to be cleaned with mild soap and water or low-pressure air

This genuine Mitsubishi replacement part is essential when a system experiences erratic signaling or power surges that compromise the existing printed circuit board (PCB)

Caleffi ZVR104 Relay 319852-301 also identified as the SA-12SThe 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