How to fix the Waste King H711 Dripping FaucetI have been using hot water dispensers for 25 years. I went through so many InSinkErator brand “Hot Taps” that I lost count. They would last 2 or 3 years and fail.In 2009 I decided to try the Waste King H711-U and it lasted an incredible 5 years and 3 months.I also liked it better that the InSinkErator “Hot Taps”. It had a larger capacity tank, better flow rate and a better faucet. Several of the copper tanks in the old InSinkErator models had failed, so the stainless steel tank in the Waster King sounded like a good idea.When the heater coil in my H711 corroded and burned out after 5 years I bought a second one without hesitation. I have had more issues with the second unit. At a year of age the tank stopped reaching full temperature. Customer support worked with me and with some effort I could get it to 180 degrees when set at max. They replaced the tank free of charge!Unfortunately, the faucet started dripping occasionally just after 1 year of age. It would drip for a few days and then stop for a few weeks. However at about 17 months of use, it became a fast steady dripping and needed to be fixed. This seems to be a top cause of negative reviews here.I asked Waste King customer support if this valve could be serviced, perhaps a washer or o-ring could be replaced. They were nice but said it was sealed and could not be serviced. They said it had to be replaced. They also acknowledged the odd fact that most suppliers sold just the replacement faucet assembly for more money than the entire H711-U installation including the tank, fittings and faucet. As of this writing, Amazon charges just one dollar less for the faucet than the whole kit. Better to buy the whole thing and have a spare tank if you need it.So, I was faced with replacing the whole unit. With nothing to lose, I decided to attempt repair. I was successful and it may be a very easy repair or a moderately difficult repair depending on your situation. Mine was the latter. Here is what fixed my HL711-U faucet:First, you need to be reasonably comfortable with plumbing and hand tools. You don’t want to flood your kitchen with near-boiling water.Step 1: Before working on this appliance, please unplug it and wait for it to cool down or run the water until it is cool.Step 2: Turn off the water supply to the H711. If the water is on, you will make a fountain in your kitchen when you open the valve. If you didn’t do step 1, you will make a fountain of near boiling water.Step 3: Repair the leak.I had to fully tear down the faucet and so I uninstalled it before taking it apart. To remove the faucet, you have to disconnect the two water lines from the tank and remove the nut under the sink that holds the faucet to the sink deck.If you are very lucky, you may be able to fix the faucet QUICKLY without even removing it.The first picture is of the valve mounted on a sink. There is a nut that holds the valve parts together. You can remove this with a 3/4” crescent wrench or an adjustable wrench. There is a white plastic plunger under the valve lever. It has a strong spring below it and you should be careful when you remove the nut and faucet lever. My valve was stuck and did not fly apart when I disassembled it.Note the angle of the faucet lever and the position of the slotted metal collar below it so that you can return the lever to its original orientation. (When you re-assemble the faucet, you can actually rotate these two pieces to make the faucet lever work sideways if you prefer.)If you look at the second picture you will see what is below the faucet lever. The white plastic plunger has two 1/4" o-rings. In my case, the bottom o-ring was damaged and causing the leak.If the plunger comes out and you see that the o-ring is damaged (or now missing) replacing this o-ring will stop the leak. This is a standard 1/4"x1/8”x1/16” faucet o-ring available at any hardware or big-box DIY store. (See the third picture, I bought mine at Lowes for $0.50)In my case the o-ring had become jammed in the bottom of the valve and the white plastic plunger could not be removed. This required some significant extra effort to fix. This is where it became apparent that the customer service people were telling the truth. If the plunger does not pop out, then you have to disassemble the whole valve.To remove the whole valve core shown in the picture, you need a 17/32” socket that will fit into the hole that you have opened in the top of the faucet. 17/32” is an odd size and is not in many socket sets. The only 17/32” socket I had was slightly too large to fit in the hole. I had to use a bench grinder to grind it down a bit to fit. This is the hard step and if you can’t get a wrench or socket down that hole you are finished.You will have to remove a slotted metal cylinder (not shown) that is just sitting in the hole. This is the slotted piece that the faucet lever rests in and which determines its orientation.At the bottom of the hole you will see the nut (marked on the second photo). Once I reached that nut at the bottom of the hole with a socket, it came out easily. I then had the whole assembly as shown in the picture.Clean out the damaged o-ring bits, replace the o-ring and re-assembled the valve.When re-assembling, the two larger o-rings rest on the smooth areas marked in the picture.The repaired plunger with two good o-rings easily slid into place but had to be held down against the spring until the nut holding the lever down was replaced.It has now worked perfectly for over a month dispensing at over 190 degrees.---------------------------------------------------------------------December 2017 UpdateThe repair lasted less than 8 months before the dripping began again.Since I had the disassembly process all figured out and I had the tools, it took only about 1 minute to get the valve apart and see the problem. The same o-ring was again bulging out and causing the leak.Though I could easily see the problem, the O-ring proved quite difficult to remove. The original O-ring easily came out in pieces. The replacement O-ring that I bought in a local big-box store was a LOT more sturdy and could not easily be ripped out in pieces. The trick that finally worked was to use a sharp pin.Puncture the O-ring with the pin and then compress the spring. Pry the O-Ring out slightly and release the spring. The O-ring will now be pinched slightly further out of the groove. Repeat 3 or 4 times and work the o-ring further out of the groove in the plunger. You can then pull out the O-ring with a pair of tweezers while compressing the spring.1. Unplug hot water dispenser and allow to fully cool.2. Turn off water supply and observe that dripping stops.3. Use a 3/4” crescent wrench or an adjustable wrench to remove the nut under the faucet lever.4. Remove the slotted collar with tweezers or fine needle-nose pliers.5. Use the 17/32” socket to remove the whole valve core6. If the valve doesn’t come apart, you will have to depress the white plunger to compress the spring while working to remove the o-ring. (I did this by pressing the assembly down onto a hex-nut that was smaller than the plunger.) Once the o-ring is removed, the assembly slides apart and a new o-ring can be easily installed.It was suggested that a “Viton” o-ring might last longer and reduce the frequency of repairs.I will try that if another repair is needed and post an update.