Operation/external diagnostics - when any thermostat calls for heat, the appropriate zone valve is energized and the yellow light goes on|When the zone valve is fully open, the red light goes on and energizes the end switch relay|The green light should always be on, indicating that power is connected|Priority operation - when zone 4 is switched to the priority setting and is actuated, all other zones will stop operation until zone 4 is satisfied|When zone 4 is not switched to priority, all zones will operate independently|When a circulator is used on the priority zone instead of a zone valve, jumper 3 and 4 of the priority zone|Priority protection operation - when the priority zone calls continuously for more than one hour, power is returned to all the other zones, allowing each zone to function independently|Once the priority zone is satisfied, the control's auto-reset is activated and the priority zone is again allowed to have priority for up to one hour starting from when it calls next
Taco Zone Valve Control, Series: ZVC, 4 Zones, 120 VAC, 1/6 hp, DPDT, For Use With: System Pump, 7 in Height, 10-3/4 in Width, 2-3/4 in Depth, Domestic