Rain Dial RD-900: Zones 1 & 2 Low Voltage — Check for Short

Zones 1 & 2 show 7–8 VAC + 14 VDC (should be 24 VAC, 0 DC). DC component = fried triac (AC switch) on board.

Test

Disconnect wire from terminal 1.
Measure voltage at terminal → 24 VAC? If yes, short in field (wire or solenoid).
If still low → board failed.

Missing ground can allow surge damage. Connect if absent.

Local irrigation shop may repair board cheaper than replacement.

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