Caleffi ZSR104 - Z-one™ Relay (four zone)
MULTI-ZONE PUMP CONTROL.
The ZSR104 is a multi-zone pump and boiler operating control for multiple zone hydronic heating or cooling systems. The ZSR104 interfaces with low voltage thermostats, or any other low voltage controllers having a switching action. The ZSR104 controls up to 4 heating circulator pumps, a primary pump and has LED indicators to provide functional status and easy system troubleshooting.