Rheem Water Heater - Manual (Page 46)

CONNECTIONS – ELECTRICAL
46
MANUAL CONTROLS
Rheem recommends an additional manual isolating switch be installed in the
power supply circuit to the booster heating unit. This booster switch is to be
installed in a convenient location such as the kitchen or laundry and will enable
the householder to control the electrical boosting during periods of poor solar
gain.
A suitably rated single-pole
on / off switch or timer control switch should be
used to control a booster heating unit connected to an Extended Off-
Peak / time-controlled electricity supply. The timer control switch should be a
type which has an internal rechargeable battery to keep time when the power
supply is not available to the timer.
A booster heating unit connected to a continuous / time of use electricity supply
should be controlled by either a suitably rated single pole
on / off switch or
“One Shot Control” switch or timer control switch .
Refer to the manufacturer’s instructions supplied with the switch for installation
details. Discuss the manual switching arrangements with the householder.
The timer control switch should be set to suit the hot water consumption pattern
of the household. It is recommended only one or two periods per day, prior to
peak hot water consumption periods, be programmed into the timer. Suggested
periods, based on a 3.6 kW heating unit, are:
• between 4:30 PM and 6:30 PM (270 model),
and if a second boost period is required,
• between 4:30 AM and 6:30 AM (270 model).
This will be sufficient for most installations. If the water heater has a 4.8 kW
booster heating unit, these periods could be reduced by 30 minutes with the
start time delayed, or a 2.4 kW booster heating unit, extended by 45 minutes
with the start time brought forward.
A manual on / off switch can also be installed in between the timer control
switch and the water heater. This can be used to provide further control over
the boosting of the water temperature.