My faucet started leaking after about 3 years, it was fixed by replacing the O-rings.
Mine is called Anaheim Manufacturing Waste King Quick & Hot. It goes by some other names and brands too, if your faucet looks like the pictures then try this.
- needle nose pliers
- electric hand drill
- Small drill bit ~5/64"
- Small screw
- At least two #60 O-rings (1/4" O.D. x 1/8" I.D. x 1/16") part Danco 96774
- Plumbers grease (optional)
Step 2: Remove the Recessed Nut
Turn off the water supply and unplug.
Push needle nose pliers in the holes and turn counter-clockwise to unscrew the nut. If you are worried about scratches, put some masking tape around the area to protect the metal. If someone finds the proper tool to unscrew the nut let me know and I'll update.
Step 3: Drill a Hole Into the Plunger & Replace the O-rings
Drill a small hole into the top of the plastic plunger towards the middle. Just make it deep enough for about 2 threads of the screw to go in. Use the screw to pull out the plunger.
Remove the old o-rings with your finger nails, tooth picks or plastic only. If you use something harder than plastic like metal, you can scratch the plastic and it will never seal. It may help to user your fingers to squish the o-ring towards one side, then get a toothpick underneath.
Put the new o-rings on.
Step 4: Reassemble & Test
Put optional plumbers grease on the threads to allow easier removal next time.
Slowly turn on the water supply and check for leaks. Turn down the temperature dial and plug it in, test, then turn up the temperature to normal.
The last picture is of a Sonin Leak Detector purchased from Harbor Freight for ~$12, the newer model is linked below. I highly recommend putting these underneath your instahot, dishwasher, clothes washer, hot water heater, ice maker, sinks and toilets in your home. They have saved me thousands of dollars in repairs! The Sonin's beep when the batteries get low which is a handy feature.