As I said, there is one thing I am puzzled about: you measured 28VAC between COM and zone 2, and you have the solenoid wires plugged into COM and zone 2 when you did the measurement, and you said it doesn’t activate the solenoid. This I really cannot explain — whether triacs inside are burned or not, or whether the controller is working or not, 28VAC was clearly present between COM and zone 2 when you measured it, why does it not activate the solenoid? I cannot explain. This is like saying: I measured 28VAC across a resistor, but there is no current detected in resistor. How is this possible? I don’t know. This defies physics.