Rheem 491 Owner's Manual And Installation Instructions page 38

CONNECTIONS – ELECTRICAL
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 TWIN ELEMENT ELECTRIC WATER HEATERS
NON-SIMULTANEOUS OPERATION OFF-PEAK CONNECTION
Top thermostat – fixed setting
Bottom thermostat – tradesperson adjustable
Electrical Circuit for Twin Element Models – Robertshaw "ST" Thermostats
The active from the continuous supply must be connected to the top heating unit
circuit and the active from the Off-Peak or time controlled supply must be
connected to the bottom heating unit circuit.
60°C.
min 60°C, max 70°C.
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