tekmar 365 Mixing Control - Manual (Page 14)

Copyright © D 365 - 06/00 14 of 16
90
70
50
30
10
Power WWSD
UnOcc.
Switch
Min.
Return
Boiler
Heat
Demand
Max. or
Setpoint
Pump
% of full
output
Test
90
70
50
30
10
Power WWSD
UnOcc.
Switch
Min.
Return
Boiler
Heat
Demand
Max. or
Setpoint
Pump
% of full
output
Test
Power light on — Test light on — Decreasing "% of full output" lights on — System Pump
light on — Boiler light on
After 10 seconds of the system pump running the control leaves the system pump on and
turns on the boiler relay for 10 seconds.
During this 10 second step, if there is a heat demand signal, and the Test button is
pressed, the test routine will be halted and the system pump and boiler will remain on.
The "Test" light will flash, and the control will be held in a pause mode for 5 minutes, after
which time it will automatically exit the test routine and cycle into normal operating mode.
Pushing the Test button during the 5 minute pause will allow the control to resume the
test routine at the next step.
Power light on — Test light on — Decreasing "% of full output" lights on
The control turns off the boiler and system pump and continues to ramp down the 4-20 mA / Variable speed
pump outputs.
If the Test button is pushed once during this step, the "Test" light will flash, and the control will be held
in a pause mode for 5 minutes, after which time it will automatically exit the test routine and cycle into
normal operating mode. Pushing the Test button during the 5 minute pause will allow the control to exit
the test routine.
90
70
50
30
10
Power WWSD
UnOcc.
Switch
Min.
Return
Boiler
Heat
Demand
Max. or
Setpoint
Pump
% of full
output
Test
Power light on — Test light off
The control has exited the test routine, entered operating mode and will function according to the
sequence of operation described on pages 5, 6 & 7. One or more of the indicator lights may be on. Refer
to pages 5, 6 & 7 for a description of the possible indicator light combinations under operating conditions.
90
70
50
30
10
Power WWSD
UnOcc.
Switch
Min.
Return
Boiler
Heat
Demand
Max. or
Setpoint
Pump
% of full
output
Step Eight Troubleshooting
As in any troubleshooting procedure, it is important to isolate a problem as much as possible before proceeding. The Error
Messages and Test button greatly simplify troubleshooting of the Mixing Control 365. When the control is flashing an Error
Message, identify the fault from the look-up table on the next page and then follow standard testing procedures to confirm the
problem. If you suspect a wiring fault, return to steps four and five and carefully check all external wiring and wiring connections.
Notes:
When a fault occurs in Reset Mode
• If the Outdoor Sensor develops either a short circuit or an open circuit, the control is programmed to calculate the outdoor
temperature at 32 °F (0°C), and control the supply temperature accordingly, subject to the limit of the supply maximum
setting. An error message will then be displayed (see error messages).
• If the Supply Sensor develops either a short circuit or an open circuit, the control is programmed to fully close the mixing
valve and turn off the variable speed pump and boiler. An error message will then be displayed (see error messages).
• If a 2k RTU or a 10k Indoor Sensor or Zone Control is connected and an open circuit develops, the control will operate at the
setting of the Occupied and Unoccupied dials. No error message will be generated.
• If a short circuit develops at either the 2k RTU – Com Sen or 10k Sen – Com Sen terminals, the control will operate at the
setting of the Occupied and Unoccupied dials. An error message will then be displayed (see error messages).
• If a Boiler Return Sensor is connected and an open circuit develops, or if no sensor is installed but the "Minimum Boiler Return"
dial is set up from the off position. An error message will then be displayed (see error messages).
• If a short circuit develops at the boiler return sensor terminals, the Boiler Return function will become inactive. An error message
will then be displayed (see error messages).
• If the enclosure overheats, the control will shut down its outputs and display an error message (see error messages) until it
cools off again. Check to ensure that the ambient temperature is less than 104 °F(40°C).
When a fault occurs in Setpoint Mode
• A short circuit or an open circuit at the Outdoor Sensor terminals will not affect the operation of the control. In the case of a
short circuit, an error message will be displayed (see error messages). An open circuit will not cause an error message to be
generated.
• If the Supply Sensor develops either a short circuit or an open circuit, the control is programmed to fully close the mixing
valve and turn off the variable speed pump and boiler. An error message will then be displayed (see error messages).
• A short circuit or an open circuit at the 2k RTU or a 10k Indoor Sensor or Zone Control terminals will not affect the operation
of the control if these terminals are not being used. In the case of a short circuit, an error message will be displayed (see error
messages). An open circuit will not cause an error message to be generated.
• If a short circuit develops at either the 2k RTU – Com Sen or 10k Sen – Com Sen terminals, the control will operate at the
setting of the Occupied and Unoccupied dials. An error message will then be displayed (see error messages).
• If the enclosure overheats, the control will shut down its outputs and display an error message (see error messages) until it
cools off again. Check to ensure that the ambient temperature is less than 104 °F(40°C).