Operation: When the thermostat calls for heat, the circulating pump is energized and the isolated end switch (X and X) will start the boiler.
Priority Operation: When the priority dip switch is set to ON and the zone is actuated, all other connected zoning panels will stop operation until the zone is satisfied. When the priority dip switch is set to OFF and the zone is actuated, all other connected zoning panels will operate independently.
Mode Operation:When the mode dip switch is set to NORMAL, the end switch relay will be energized if any zone is in operation. When the mode dip switch is set to RESET, the end switch relay will only be energized through the operation of a plug-in reset control or closure of Priority Input.
Primary Pump Operation: When the dip switch is set to OFF, the primary circulating pump output will not energize when zone calls for heat. When the dip switch is set to ON, the primary circulating pump output will energize when zone calls for heat.
Post Purge Operation: When the dip switch is set to ON, the circulation pump output will stay energized for 2 minutes after its thermostat or aquastat is satisfied, but not operate the boiler.
Priority Protection Operation: When the dip switch is set to ON and the zone (priority) on master zone panel calls for heat continuously for more than one hour, then power is returned to the space heating zones allowing all the zones to function independently. Once the zone (priority) on master zone panel is satisfied, the control’s auto-reset is activated and the zone is again allowed to have priority for up to one hour.
Pump Exercise Operation: When the dip switch is set to ON, the solid state timer cycles all the circulating pumps that are attached to the Expandable Switching Relay at the selected time interval. The time interval can be set for the pumps to run for either 30 seconds every 2 weeks or for 4 minutes every 24 hours.
End Switch: The switch closes when the thermostat calls for heat and the mode switch is set to NORMAL. The end switch also closes when the mode switch is set to RESET and a PC Series boiler reset power control is calling for heat.
Expansion Connections: Set the expansion switch to MASTER on the switching relay that has the designated priority zone or is utilizing the PC Series plug-in option. Set all other daisy chained controls to SLAVE. Using thermostat wire (18-22 gauge) connect between terminals A, B, C on the master control to the corresponding A, B, C on the SLAVE control(s). Controls may be daisy chained up to 20 zoning panels using any combination of -EXP controls (120 zones if all are 6 zone panels).
Technical Specification and Instruction Sheet
Product Wiring Diagrams and Examples