Adding a Second Valve to Hunter XC: Common Wire Wiring

Expanding a Hunter XC from one to two valves is straightforward: the controller has a single common (C) terminal, and all valves share one common wire in the field. Here's how to wire it correctly at both ends.

Controller Side

• One common terminal labeled "C" or "COM"
• Existing common wire already connected
• Do not add a second wire to the C terminal—use the existing common

Valve Box Side

You'll see multiple white (common) wires spliced together. This is the shared common bundle. To add valve 2:

1. Identify the common splice (usually a waterproof connector joining 2+ white wires).
2. Add the new valve's common wire to this same splice.
3. Connect the new valve's "hot" wire (distinct color) to the zone 2 terminal at the controller.

Identifying the Correct Common Wire

If commons aren't pre-spliced (rare), you can:

• Trace wire from existing working valve's solenoid—one lead goes to common bundle.
• Use a multimeter: with controller off, check continuity between controller C terminal and each white wire in valve box.
• Or simply twist all white wires together in a new waterproof connector—all solenoids share common.

Key Points

• Each valve needs: one unique hot wire (to its zone terminal) + one common wire (to shared C)
• Wire nuts must be waterproof (gel-filled or silicone-sealed)
• Leave slack for future maintenance
• Test zone 2 manually at controller after wiring

Reference

Hunter XC manual: lit397enw.pdf