Watch this how-to video or follow these steps:
Let the water run until both hot and cold water is fully mixed.
Rotate the handle fully counterclockwise to the hottest position.
Place a thermometer in a plastic tumbler, and hold the tumbler in the water stream.
If the water temperature is above what is allowed by your local plumbing code (110º F or 120º F), remove the handle on 1300/1400 series or temperature knob on 1700/1800 series, and rotate the rotational limit stop:
a. Counterclockwise if you have a Monitor® 1300 or 1400 series model (handle controls the temperature only, not the volume). For every tooth the rotational limit stop is rotated counterclockwise, the maximum water temperature will decrease approximately 6º F. NOTE: If water temperature is too cool, rotate the limit stop clockwise.
b. Clockwise if you have a Monitor 1700 or 1800 series model (handle controls volume; temperature knob controls temperature). For every tooth the rotational limit stop is rotated clockwise, the water temperature will decrease approximately 2º F. NOTE: If water temperature is too cool, rotate the limit stop counterclockwise.