A.O. Smith AHPW-25, Руководство пользователя

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21
Notice: Please make sure you are running a
Johnson controller (page 20) before you con-
tinue to the next page. If you are running a PLC
(Programmable Logic Controller) skip to the
directions starting on page 22.
FUNCTION RANGES & SETTINGS
Some of the A421 controllers settings are preprogrammed
by AO Smith before shipment. These settings along with
parameter ranges have been provided for your reference in the
Parameter Settings table below.
SCREEN NAVIGATION
The A421 control buttons and display operate the same in
both Basic and Advanced mode.
• When in Menu screens the parameters and values will
fl ash on and off .
• Use the Arrow keys to navigate through all of the parameters
and values
• To select a parameter press MENU
• To save a selected value, press MENU.
• This will automatically bring you to the next settable parameter
• To exit menus and return to the main screen press both
arrow keys simultaneously.
Note:
If you do not press MENU to save a new value, the
control reverts to the last saved value.
After 30 seconds of inactivity, while in any screen, the control
reverts to the Main screen.
Saved settings remain in the control’s memory during power
interruptions.
BASIC MODE
In this mode you can adjust the OFF, On, SF and ASd Parameters
ONLY. Most adjustments that are needed to run your unit will
be performed in this mode.
Basic Mode Menu: From the main screen press MENU once.
The screen will display the fl ashing OFF parameter indicating
that you have entered the menu.
OFF: This parameter indicates your desired high temperature.
When this temp is reached the unit will enter a cool down
mode until the On value is reached. WARNING: Never set
above 160°F.
ON : This parameter indicates your desired low temperature.
When this temperature is reached the unit will enter heating
mode until it reaches the OFF value again.
ASd : The Anti-Short Cycle Delay indicates the time required
for the unit to wait before running again. This parameter is set
to 0 min because AO Smith units come equipped with safety
timers already in place.
SF : Sensor Failure indicates that the temperature sensor has
failed.
bLL: Black Light Level indicates the brightness of the LCD
screen.
ADVANCED MODE
In Advanced mode you can adjust all of the basic parameters
as well as; Un, Tsb, So, HtS and LtS. The main function of this
mode is to add more control over your unit and to set restrictions
for parameters in basic mode.
Advanced Mode Menu: From the main screen press and hold both
arrow keys simultaneously. The screen will display the fl ashing
Un parameter to indicate that you have entered the menu.
Un: Indicates the temperature units. This can be in either Fahrenheit
(°F) or Celsius (°C).
LtS: Low Temp. Stop indicates the lowest temperature that the
On or OFF parameters can be set to in Basic Mode.
HtS: High Temp. Stop indicates the highest temperature that
the On or OFF parameters can be set to in Basic Mode.
tSb: Temp Setback indicates the value for setting back the On
and OFF temperature values. Default to 0°F because it is not
applicable to the application of this unit type.