Taco SR503-EXP Zone Switching RelayThe Taco SR503 EXP is a 3 Zone Switching Relay for circulators with priority control and three powerports, built to simplify hydronic heating installations. This compact module manages up to three independent zones, prioritizing one zone when demand requires it to optimize boiler efficiency and comfort. Its robust design supports safe operation, easy wiring, and long term reliability in both residential and light commercial settings. It supports

delivering consistent performance across temperature ranges and pressure levels

White-Rodgers 1F80-361 Thermostat is a versatile programmable thermostat designed for comfort and energy savings

and rooftop systems

a robust ceramic material known for high-temperature stability and long life in demanding combustion environments

The Robertshaw 720-055 Gas Valve uses a durable lever actuator and operates on 24 Volt AC (0

durable operation in compact panel applications

and extend the life of your split system

Terminals: 1/4 inch quick-connect

and heat exchangers without sacrificing airflow

Voltage: 24 Volt AC

Durable construction: Robust valve body for reliable operation

Proportional Valve for precise mixing