tekmar 421 Mixing Reset Module - Manual (Page 17)

17 of 20 © 2007 D 421 - 08/07
Error Message Description
ADJUST ERROR
The control failed to read the Adjust menu settings, and reloaded the factory default settings.
Operation stops until you check the Adjust menu settings.
Note:
To clear the error, the access level must be set to Advanced and the settings in the
Adjust menu must be checked.
MISCELLANEOUS ERROR
The control failed to read the Miscellaneous menu settings, and reloaded the factory default
settings. Operation stops until you check the Miscellaneous menu settings.
Note:
To clear the error, the access level must be set to Advanced and the settings in the Misc
menu must be checked.
MIX BUS ERROR
Communication has been lost on the boiler bus. Check the tN4, C and R wires for each tN4
device. Check the polarity of the C and R wires. Check for loose or broken wires.
MIX BUS DEVICE LOST
Communication is lost to tN4 device AA on the Mix bus. The LCD on the lost device displays
Bus 1 OPn. Ensure that there is power to the lost device. Trace the wires from the control to
the lost device looking for loose or damaged wires. Once the error is corrected, press any
button to clear the error.
Note:
If you deliberately remove a tN4 device, hold the Up and Down buttons to clear the error.
MIX MODULE ERROR
A Mixing Module has been connected to the Mix bus. Ensure that there is not a Mixing Module
on the Mix bus.
MIX SENSOR SHORT CIRCUIT
Due to a short circuit, the control failed to read the Mix supply sensor. As a result, the control
operates mixing device at a fixed output as long as there is a call for heat. Locate and repair
the problem as described in the Data Brochure D 070.
MIX SENSOR OPEN CIRCUIT
Due to an open circuit, the control failed to read the Mix supply sensor. The control operates
the mixing device at a fixed output as long as there is a call for heat. Locate and repair the
problem as described in the Data Brochure D 070.
BOILER SENSOR SHORT CIRCUIT
Due to a short circuit, the control failed to read the boiler sensor. When there is a call for heat,
the control no longer controls the boiler(s). Instead, the control provides a boiler enable to the
boiler’s aquastat or boiler control until the sensor is repaired. The control will not operate the
boiler contact if the Boil Minimum setting is less than 100°F (38.0°C). Locate and repair the
problem as described in the Data Brochure D 070.
Error Messages (1 of 2)