- 1). Remove the Kohler faucet handle by unscrewing the small screw on the base of the handle with an Allen wrench and sliding the handle off the faucet.
- 2). Turn the cartridge stem, the part that slides into the handle when it is on the faucet, all the way to the right in the full open position. Let the water run and test the temperature.
- 3). Adjust the small set screw on the side of the collar, which is the knob on top of the cartridge stem, to increase or decrease the temperature slightly. This collar slides over the stem, and it contacts the limit stop, a square knob on top of the cartridge, to prevent the handle from rotating too far.
- 4). Test the water temperature with a thermometer and look for a reading around 105 degrees Fahrenheit but never over 120 degrees Fahrenheit. If this does not solve the problem, loosen the screw and slide the collar off the faucet.
- 5). Set the temperature by turning just the stem with a pair of pliers. Once the temperature is set perfectly, install the knob so the screw is flush against the limit stop, the square knob on the side of the cartridge stem.
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