State Water Heaters SUF60 Service Handbook page 23

ACTION:
Press Change then use the UP and DOWN buttons to change the Operating Set Point.
DISPLAY:
Note: This procedure can also be used to change the Differential. The Tank Upper and Lower Temperatures
are not user changeable. They are determined by the temperature probes on the heater.
ACTION:
Press Update to accept the change or Cancel to reset it.
DISPLAY:
Servicing should only be performed by a Qualified Service Technician 21