Troubleshooting
I
6-15
6
Troubleshooting
Unit Faults
The Thermolator has detected a problem with the internal components, wiring, electrical power, or operat-
ing environment. Without correction, the fault could lead to equipment damage or personal injury if it is
not corrected.
•
The controller displays an error code indicating the cause of the problem.
•
The TCU may take automatic control actions, based on the nature of the fault, to best protect the op-
erator and the TCU until the fault is corrected.
•
If the optional alarm package is installed, the fault strobe will illuminate and the audible alarm will
activate.
•
Some faults require a power cycle to reset.
Fault
Possible Cause
Solution
tcU
ht
Hardware Over-Temperature
Trip
The temperature of the process
fluid bypass tube has exceeded
the maximum permissible operat-
ing temperature.
For models with SSR’s, this fault
can also refer to an overheated
SSR heatsink.
WARNING:
Only qualified elec-
trical service personnel should
examine and correct problems
that require opening the unit’s
electrical enclosure or checking
electrical current.
u
ALARM LED illuminated.
u
Optional strobe, sounder,
dry contacts actuated.
u
Pump locks on.
u
Heater locks off.
u
Cooling valve locks open.
Power must be cycled to reset
this fault.
Has water stopped flowing
through the unit or between the
supply outlet and return inlet?
Verify that the unit is running and
that the pump is working.
Check for closed or defec-
tive cooling or vent valves and
plugged lines.
See Repairing
Cooling Valves.
Check for external closed valve on
the process fluid going to external
equipment.
Has the heater contactor (or SSR)
failed with the contacts welded
closed?
Replace the contactor if defec-
tive.
See Replacing the Heater
Contactor.
If SSR Model: Has the heatsink
fan failed or is the air pathway
blocked?
Replace the fan or clear the
blocked air pathway.
Reset the heatsink thermostat by
depressing the button on the top
of it.
Has the optional high temperature
switch failed?
Verify that the switch is closed
near room temperature with a
VOM. If not, replace the optional
temperature limit switch.
(Continued)
Summary of Contents for Thermolator TW-P
Page 6: ...iv I Table of Contents ...
Page 12: ...1 6 I Introduction ...
Page 36: ...3 14 I ...
Page 58: ...4 22 I Operation ...
Page 72: ...5 14 I Maintenance ...
Page 128: ...E 4 I Appendix ...
Page 134: ...G 4 I Appendix ...
Page 136: ...H 2 I Appendix ...