Rheem Electric Domestic Water Heater - Manual (Page 9)

HOW YOUR WATER HEATER WORKS
TWIN ELEMENT MODEL
This type of water heater has two heating units, each with its own thermostat.
One heating unit is at the base of the water heater and the other near the top.
• Bottom heating unit
During normal operation this
heating unit supplies all the hot
water.
• Top heating unit (Booster)
This heating unit only operates
during periods of high demand to
provide an additional supply of
heated water.
• Electrical connection
The two heating units are wired for
non-simultaneous operation, so that
only one heating unit can operate at
a time. The bottom heating unit is
usually connected to an Off-Peak
(overnight) or time controlled
electricity supply and the top
heating unit to a continuous supply.
Some electricity suppliers allow
both heating units to be metered at
the Off-Peak or controlled tariff.
NOTE: Power must be available to the top heating unit circuit at all times
for this water heater to operate as designed.
GOING ON HOLIDAY?
If you plan to be away from home for one or two nights, we suggest you leave
the water heater switched on. However, if you plan to stay away more than a
few nights, conserve energy by switching the water heater off at either the
switchboard or isolating switch.
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