Rheem STELLAR 4A Series Owner's Manual And Installation Instructions page 41

THERMOSTAT SETTING
The thermostat at the bottom of the water heater is tradesperson adjustable from
60°C to 75°C (60°C to 80°C on a 050 model). The factory setting of the
thermostat is 70°C for a single element 080 to 315 model, 70°C for a twin
element model and 80°C for a 050 model.
The thermostat is adjusted by turning the adjuster anticlockwise to decrease the
temperature setting and clockwise to increase the temperature setting. Only
adjust the thermostat setting when the isolating switch is switched off at the
switchboard.
The top thermostat on a twin element model has a fixed setting of 60°C.
For reasons of safety and economy, we advise the thermostat be set at the
lowest temperature that will provide sufficient hot water. Dishwasher running
costs can be adversely affected if the thermostat is set below 65°C. Discuss the
thermostat setting requirements with the householder.
WIRING DIAGRAM SINGLE ELEMENT ELECTRIC WATER HEATERS
Thermostat Robertshaw "ST" – tradesperson adjustable
080 to 315 models
minimum 60°C
maximum 75°C
050 model
minimum 60°C
maximum 80°C
CONNECTIONS – ELECTRICAL
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