Six Superior Valves Clicking After Solenoid Swap: Low Voltage Root Cause

Clicking Solenoids = Voltage Problem, Not Bad Solenoids

6 of 9 Superior valves clicked, user replaced all 6 solenoids (or just plungers). Clicking persists. Voltage test revealed only 5 VAC at valve (should be 22–26).

The Real Culprit

Controller outputting low voltage under load. Causes:

• Controller output stage failing.
• Common wire partial break (high resistance).
• Too many valves on one transformer (exceeds VA rating).

Diagnostic Isolation

1. Disconnect one valve wire at controller. 2. Test voltage at that terminal (COM + Zone) with zone ON. 3. If voltage recovers to 24 VAC → field wiring issue (short/leak). 4. If still low → controller failure.

Dial Position Myth

Leaving dial on zone number doesn't cause clicking. The "start" position just exits manual mode. Voltage should be steady regardless.

Fix Path

Most likely: controller output transistor failing. Replace controller. Keep new solenoids as spares.