A.O. Smith DRE-52 Series, Инструкция по эксплуатации

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differential settings
Adjustable user setting(s) 1°F to 20° range; factory default is 2°F.
The water heaters covered in this Instruction Manual will have 3, 6 or
9 heating elements. Each group of 3 heating elements is one “Bank” of
heating elements. Heating elements are energized in Banks of 3. Each
Bank of heating elements will have a Differential Setting associated
with it. Differential Settings are located in the Temperatures Menu.
There is a 1st Differential Setting on all models. There will be one
additional Differential Setting visible/adjustable for each additional
Bank of (3) heating elements.
operating sequence
With an Operating Set Point of 120°F and all Differential settings at 2°F
the On/Off sequencing of heating element Banks would be as follows:
BANK NUMBER
DIFFERENTIAL
SETTING
TURN ON
TEMP
TURN OFF
TEMP
Bank 1 2°F 118°F 120°F
Bank 2 2°F 116°F 118°F
Bank 3 2°F 114°F 116°F
tank temperature
Non adjustable information display. Current water temperature as sensed
by the control system from the immersion Temperature Probe.
tank Probe offset
User adjustable setting -5°F to +5°F range; factory default is 0°F. If the
current Tank Temperature is sensed (from the immersion Temperature
Probe) at 120°F and the offset is adjusted to -5°F the control system
would calibrate or “offset” the Tank Temperature to 115°F. Heating cycles
would then start/stop based on the calibrated Tank Temperature.
Used to calibrate for slight differences in control system temperature
sensing. This can improve the precision of temperature control in
the storage tank and at points of use. This feature can also be
used to compensate for building recirculation loops (hot water
returning to the storage tank) that may cause the heating cycle to
terminate prematurely.
tEMPErAturE sEttInGs
The Operating Set Point and the Differential Settings are adjusted
in the Temperatures Menu. The following instructions explain how to
adjust these user settings and navigate the control system menus.
ACtIon dIsPLAy
From the Desktop Screen, press the Operational Button underneath “MENU”
to enter the Main Menu.
Notice how the text above the Operational Buttons on the display changes
as you navigate through the various menus and screens.
With Temperatures selected (highlight in black) in the Main Menu, press
the Operational Button underneath “SELECT” to enter the Temperatures
Menu.
If Temperatures is not selected use the Up and Down buttons to select this
menu item.
With the Operating Set Point selected in the Temperatures Menu, press
the Operational Button underneath “CHANGE” to activate the adjustment
mode for this menu item.
Press the Up and Down buttons to adjust the Operating Set Point to the
desired setting.
Press the Operational Button underneath “UPDATE” to confirm the new
setting. Press the Operational Button underneath “CANCEL” to discard the
new setting and retain the previous setting.
The new Operating Set Point value should now be displayed as the current
value.
NOTE: Use this same procedure to adjust the Differential settings and the
Tank Probe Offset in the Temperatures Menu.
This same procedure is used to change user settings in other control system
menus.