tekmar 421 Mixing Reset Module - Manual (Page 16)

© 2007 D 421 - 08/07 16 of 20
Error Messages
Local Errors and Device Errors
Error messages are used to indicate a problem somewhere in the system. There are two types of error messages: Local
Errors and Device Errors.
A Local Error indicates an error specific to a device. For example, a thermostat with a sensor short circuit will show a Sensor
Short Error on its display. No other devices will show this specific error (unless they also have a sensor short circuit).
A Device Error is used to indicate that there is a local error somewhere else on the system. For example, if a thermostat
has a sensor short circuit, that thermostat will show a Local Error indicating specifically what the problem is. All other
devices on the network will show Device Errors, indicating the address of the device with the Local Error. In other words,
Device Errors are nothing more than pointers, showing you that there is a local error somewhere on the system and where
to find it.
Error Priority
Only one error can be shown on a particular device at a time. If there is more than one error on the system, the highest
priority error will be the one that is shown. The table on pages 22 and 23 lists error messages in order of high priority to
low priority.
How to Locate an Error Message
If the warning symbol (flashing circle with exclamation mark) is visible on screen, this indicates that there is an error
somewhere on the system. To view the error message, you must first put the control into the Advanced or Installer access
level (available in MISC menu). When an error message is present, it is available as an item in the VIEW menu.
Device is attempting to
show supply temperature
but cannot because of
sensor problem.
Keep pressing the Item
button to find the actual
error message
Once error is corrected,
the temperature can be
displayed
If the error message is a Device Error (if “DEV” or “DEV ERR” is shown on screen), read the address shown and go to the
device with that address. That device will have a Local Error indicating specifically what the problem is. When the problem
is corrected, the error message will automatically clear.
Access Levels
In some cases, it is not desirable to let day-to-day users view error messages. In these cases, by lowering the access level
of the thermostat or setpoint device to ‘User’ or lower, error messages cannot be seen in the View menu and the warning
symbol only appears if there is a local error or a device error caused by a critical error on another device. If there is an error
message on the system that you cannot find on a particular thermostat, make sure that the access level on that thermostat
is set to Installer or Advanced.
Sensor Temperature Errors
If a control is unable to display a temperature due to a sensor malfunction or communication problem, the word “Err” is
displayed in place of the temperature. This usually indicates that there is an error somewhere on the system but is not the
actual error message. Keep looking through the View menu to find the actual error message.
While in the View Menu, press the item button until the error message is displayed. You may have to advance through
several View Menu items before the message is displayed.