Installation for:

See wiring for Prioritized Indirect Fired
DHW Tank (boiler with integral pump relay)

The wires from the first thermostat connect to TS1 and the corresponding wires from the zone valve connect to ZV1. This goes for TS2 and ZV2, etc. If there is only one or if this is the last Zone Valve Controller, then the line out on the circuit board is connected to the boiler and circulator control.

 

When networking more than one Zone Valve Controller, the line out on Zone Valve Controller 1 is connected to the line in on Zone Valve Controller 2, and the line out on Zone Valve Controller 2 is connected to the line in on Zone Valve Controller 3, etc.

See the wiring diagram for multiple
MDC2001 Zone Valve Controls

In the case where the 24 VAC Relay is used to control the circulating pump which does not have an integral transformer, set the jumper JP2 (Slave) to JP1 (Master). This provides the relay with the required voltage to operate the switch.
If a number of Zone Valve Controllers are networked, the jumper JP2 (Slave) is set to JP1 (Master) on the first controller ONLY.

In the case where the 24 VAC relay does have it's own transformer or it has it's own separate transformer then set the jumpers to the JP2 (Slave) position on all controls.

See wiring diagram for
Circulator Control - Option A

See wiring diagram for Circulator Control Option B

See wiring diagram for Circulator Control Option C