Q: I have a York HVAC system, and the inside blower motor is running continuously. In addition, yesterday, I noticed marks coming from the capacitor outside of the blower housing. I turned the unit off, and there was also water dripping on the outside of the unit.  The HVAC unit runs fine today, but I didn’t want to take my chances so I turned the unit off from the breaker box.
Questions:
1. What is causing the water to be dripping down onto the blower housing?
2. What could cause the sparking (burned wires) on the capacitor?
3. What could be causing the blower motor to be continuously running even when I turn the thermostat to “off”?

It sounds like the system has an iced up coil and the water is shorting out the blower capacitor. The blower relay may also be damaged due to the dripping water. You need to call in for service and check the filters as well as the refrigerant charge in the system. They also should check for a dirty coil and blower wheel.