The SimpleHuman automatic soap dispenser is a touch-free pump that puts soap or sanitizer in your hand when you place it under the sensor. These are great in dispensing soap without having to touch anything but over time the soap can dry out (or if you use too thick a soap) and form a blockage in the tube leading from the pump to the dispenser port.
If this happens, the pump will whine but not dispense any soap. Sometimes you can flush it with water or thinner soap but if the blockage is too thick the only way to fix the problem is to disassemble the pump and remove the blockage.
The instructions in this Instructable allowed me to repair a soap dispenser that was so gunked up that the motor wouldn't turn. This Instructable is for a SimpleHuman dispenser with two buttons on the top of the dispenser. I have a different Instructable for a dispenser without the buttons on top https://www.instructables.com/id/Unclogging-a-SimpleHuman-Soap-Dispenser/
Step 1: Remove the Top
The top is held on by two screws which are visible once you remove the filling port cover and a third screw from the bottom of the spout.
Step 2: Disconnect Cables and Spout
Disconnect the black/red wire for the battery and the black/white for the motor. Disconnect the spout.
Step 3: Remove and Clean Spout
The spout is attached to the feed tube which is disconnected. Then the spout is cleaned to remove any blockage. There is a very tiny hole at the bottom which is invisible but needs to be free of obstructions.
Step 4: Flush Out the Soap Feed Tube
Force hot water down the tube to clean out any soap blockages. This may be all you need to get the pump working. In my case, more work was needed.
The syringe I use is the one from my Sawyer Mini Water Filter kit. It's the perfect size for these types of tubes.
Step 5: Remove Chrome Spout Assembly
The spout assembly is removed by pulling the spout assembly outward and downward.
Step 6: Remove the Bottom
Remove two screws holding the bottom.
As you can see in this instance, the bottom is completely gunked up with dried soap and the motor and pump are covered with dried soap so as to be immoveable.
Step 7: Remove the Battery Assembly
Unscrew the two screws holding the battery assembly to the bottom assembly.
Step 8: Clean the Bottom
Remove any dried soap and dry off the bottom.
Step 9: Remove and Clean the Pump
The pump assembly consists of two sides held together with 4 screws. Two of the screws are easily removable while the other two are under the pully wheel. You may be able to pry off the wheel and get access to the other two screws but I didn't want to risk breaking the wheel so I just cleaned everything off and ran water through the pump input (on the other side of the pump assembly.
Step 10: Remove the Motor Assembly
The motor assembly is attached with 2 screws and the motor has a small pully wheel which is hard to remove. Be careful not to break the pully. I forgot to take pictures of the end of the motor but there is a rubber cover that's accessible once the small pully wheel is removed.
In this instance, the motor was unable to turn due to the dried soap and possibly rust. After careful scrubbing with a small toothbrush, the motor was reasonable clean and a light oil was applied and eventually the motor was unstuck and with repeated cleaning/lubricating the motor spun freely.
Step 11: Reassemble
Reverse the steps to reassemble the pump. As you can see, it's quite a difference from the original picture where everything was covered in junk.
The pump worked perfectly. Be careful in how you place the batteries because the image is the reverse as to what I would have expected and the motor didn't work until the polarity was reversed.
This is my second type of SimpleHuman soap pump that I've disassembled and repaired.
- Make sure your soap is thin enough to pump. Dilute the soap if necessary and bump up the amount dispensed to compensate.
- In some models you can force water into the pump output spout to force any clog back into the reservoir. This wasn't possible with this model.
- Use the soap dispenser constantly. If you don't use it for a length of time the soap will start to dry out and clog the feed tube.
- Be careful of concentrated soap. I used the Dawn Ultra Concentrated soap in one of my dispensers and that stuff if way too concentrated. It also doesn't dilute well. It also skins over which makes clogs more likely.