Thermostat Settings - Electronic Control Models; Electronic Control Models Operation; Control System Features; Control System Navigation - A.O. Smith dre-52 Instruction Manual

therMostat settInGs - electronIc controls
These models are equipped with an electronic control system. The
control system senses temperature from a factory installed Immersion
Temperature Probe (see Figure 1). The "Operating Set Point" is
adjusted to control water temperature. This is an adjustable user setting
in the control system's "Temperatures Menu." This and all control
system menus are accessed through the UIM (User Interface Module
- see Figure 5) located on the front panel of the water heater.

electronIc control Models operatIon

control systeM features

Advanced Diagnostics: Plain English text and animated icons display
detailed operational and diagnostic information. LCD screen on the
front of the water heater displays the Sequence of Operation in real
time. Fault or Alert messages are displayed when operational problems
occur. Advanced Service menu displays a list of possible causes for
current Fault and Alert conditions to aid in servicing.
Economy Mode Operation: Control system automatically lowers
the Operating Set Point by a programmed value during user defined
time periods. Helps reduce operating costs during unoccupied or
peak demand periods.
Linear Sequencing: Banks of heating elements (3 elements per
bank) are energized according to adjustable (1 to 20°) differential
set points for each bank. First bank on is the last bank off. Helps
reduce operating costs during low/moderate loads.

control systeM naVIGatIon

The UIM (User Interface Module) is located on the front cabinet of the
Electronic Control Model water heaters. All operational information
and user settings are displayed and accessed using the UIM. The
UIM includes five snap acting (momentary) user input buttons; an
Up, Down and 3 Operational Buttons.
uIM - user Interface Module
fIGure 6.
The Operating Set Point is adjustable from 90°F/42°C to 190°F/88°C.
The factory setting is 120°F/49°C. See the Electronic Control Models
Operation section of this manual for instructions on how to adjust
the Operating Set Point and other user settings.
uIM (user Interface Module)
Set the Operating Set Point at the lowest setting which produces
an acceptable hot water supply. This will always give the most
energy efficient operation.
up & down Buttons
Used to navigate (up and down) and to select (highlight) menu items.
Also used to adjust or change (increase/decrease, on/off, set time)
various user settings.
operational Buttons
The 3 Operational Buttons are multifunctional. Their current function is
defined by the text that appears above each button on the LCD screen.
The function will change depending on what menu is currently displayed
or what menu item is selected. When no text appears on the LCD
screen above an Operational Button there is no function assigned.
the desktop screen
Figure 7 below shows the control system "Desktop Screen." This
is the default screen. If there are no active Fault or Alert conditions
and no user input for approximately 10 minutes the control system
will return to this screen automatically.
Model Information
Model information and menu titles are shown in the black bar at the
top of the Desktop Screen.
tank temperature
Current water temperature as sensed from the immersion
Temperature Probe.
Operating Set Point: Temperature at which the control system will
maintain tank (water) temperature in the Normal Mode. This line of
text will read economy set point whenever the control system is
operating in the Economy Mode.
Status: The Operating State of the control system is displayed
beneath the Operating Set Point.
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fIGure 5
fIGure 7.