Caleffi ZSR104 4-Zone Expandable Switching Pump Relay

The Caleffi ZSR104 4-Zone Expandable Switching Pump Relay is a control component that manages multiple circulator pumps and zoning operations in compatible heating equipment. The component processes thermostat signals and activates pump circuits to regulate individual zone requirements with 4-zone expandable control capability. This relay works with HVAC systems such as hydronic heating and boiler units to assist with temperature zoning and pump management mounted in the control panel section. It organize switching operations and supports accurate communication between thermostats and heating circuits.