Hcwp3-18 Wiring Diagram. Diagram c bypass humidifier wiring diagram for operation during “heat call” only system checkout 1. S14 & s33 channel 1 input, active hi (closed) s22 channel 2 input, active. Sde Ma18 Wiring Diagram from schematron.org Wired in series with the humidifier water solenoid valve. White wires are common, the black wire goes […]