A.O. Smith VB/VW-500 - Manual (Page 36)

36
The software revision level of the MCB.
• Current Error Screen:
Displays the last error that the system has detected plus a
time stamp of when the error occurred. (The time stamp is
based on the elapsed hours value at the time the error
occurred. It is displayed in hours and minutes. This error
remain displayed as long as it is still valid. When cleared
it is moved to the Error History Screen. The system will
automatically jump to this screen when an error is detected.
It will also go to this screen upon power-up if an error was
still valid when power was turned off.
NOTE: Errors are cleared from this screen by pressing
the "select" key.
• Error History Screen:
This screen displays a list of the last 9 errors (with time
stamps) that have occurred. The last error to occur is
displayed first. If a new error occurs this screen is
presented to display the error.
• Reload Defaults Screen:
From this screen the user can restore the factory default
values for screen adjustable configurations by pressing
the Select key. The values restored are as follows:
VW Models
Oper Setpnt (Operating Setpoint) - 145° F (63° C)
Hi Limit (High Limit Setpoint) = 210° F (99° C)
Hi Limit Dif (High Limit Differential) = 20° F (11° C)
VB Models
Oper Setpnt (Operating Setpoint) = 190° F (88° C)
Hi Limit (High Limit Setpoint) = 230° F (110° C)
Hi Limit Dif (High Limit Differential) = 20° F (11° C)
Both Models
Tempert Units (Temperature Units) = F
Post Cir Secs (Post Circulation pump delay = 45 seconds
Network Address (Network Address) = (none)
UIM Touch Switches
Below the LCD display are five touch switches or keys, that the
operator uses to operate the system.
• Menu Key:
Pressing this key activates the menu screen where the other
screens can be accessed.
• Select Key:
This key performs several functions. Screens can be selected
from the menu screen by pressing this key when the ">" appears
next to the screen desired.
On the User Settings screen items that appear next to a ">"
symbol can be selected with this key. If a setpoint configuration
item is selected, the ">" will then flash slowly to indicate that
the item has been selected. The Up and Down keys are then
used to change its value.
From the Current Error Screen this key is used to reset the
system from an error:
• Up and Down Keys:
These keys are used to move upwards and downwards in
screens to reach a desired item and to change setpoints
and user settings. They have an auto increment/decrement
feature for some of the configurations and values. When
you first press one of the keys and value changes by 1
count, then wait 1/2 second and changes slowly until the
key is released or if held for 3 or more seconds it will
change the value quickly.
• Help Key:
Pressing the Help key from any screen displays helpful
information about that screen. From the menu screen, general
help information is displayed as to how to use the user interface.
To return to the previous screen press the Help or Select keys,
or press Menu key to go to the menu screen. If a small down
arrow appears in the lower right hand corner then there is off
screen content below what is displayed. Press the down arrow
to scroll down to this information. After scrolling down an up
arrow will appear in the upper right hand corner to indicate off
screen content above what is displayed.
UIM LED's
The three LED's to the right of the LCD indicate the status of the
overall system. The red LED indicates that a fault has been
detected and the system has stopped running. It is on continuously
for soft faults and flashes for hard faults. The Yellow LED indicates
that the boiler is in a ready mode waiting for a call for heat
command. When on continuously the Green LED indicates that
the system is in the heating mode. If it is flashing it indicates that
the UIM is in the initialization mode and the touch switches are
being calibrated.
The VF ® boiler has a display on the UIM which is a scaled display
indicating the current firing rate of the boiler (25% to 100%).
Fault Messages and Troubleshooting Guide
The EMC 5000 modulation system does excessive self-diagnostics
and displays detected faults on the UIM display in an easy to read
manner. There are approximately 80 different faults that can be
detected. Some of the faults are caused by internal problems and
some by external causes. The faults create different types of system
lockouts (shut down). Hard lockouts are serious problems that
require the user to manually restart the system. Soft lockouts can
be reset by the user or after 60 minutes the system will automatically
clear the error and restart. Auto Reset lockouts will monitor the
cause of the fault and it the fault clears itself the system resets
itself. The following table shows the fault messages and some
possible troubleshooting hints: