My VCMA-15ULS pump has started making an awful humming noise. Can I safely unplug it while keeping the furnace (Carrier Comfort 92) on? (I also have a Carrier 38TKB a/c unit, but it isn't currently being used)

SOURCE: the VCMA-20ULS pump is not shutting off

These pumps have a float arm inside that tell the pump when to turn on and off, it sounds like your arm is stuck or broken. The top of the unit can be taken off of the reservoir to check for damage.

Good luck

SOURCE: Water is dripping rapidly from my VCMA 15ULS. Do I

I assume the unit is overflowing, because the pump is not running. Check th hose connection and be sure the line bringing the water into the pump is inserted in the opening. Can you hear the motor run? You can remove the top, and be sure the float switch is working and that the pump inlet is not clogged with debris. Sometimes you'll get mold and dirt mixed with water clogging the inlet. If the motor doesn't run, and the switch works, then it probably isn't worth fixing as you can buy these from 35.00--50.00