THERMOJET
®
G-3700E SERIES
OIL PURIFIER SYSTEM
INSTALLATION AND OPERATING MANUAL
Doc #
77740151
Rev
03
Date
June 2020
Page
78
of
111
Temperature
Control
Problems
Low Oil Temperature
A.
Verify that the “heater on” light is illuminated.
B.
Verify the unit is connected to the correct power supply.
C.
Verify that the temperature controller is set at the desired operating
temperature. If the temperature controller is set to the desired temperature, then the
parameters of the PID temperature controller may have drifted and need to be
readjusted. To adjust the parameters of the temperature controller, initiate the auto-
tune function of the controller. To initiate the auto-tune function, depress the up
arrow and the down arrow keys of the controller at the same time for longer than 4
seconds. After the up key and the down key are released, the process value should
start flashing. This flashing indicates that the auto-tune function of the temperature
controller has been started. Once the controller enters auto-tune mode, the
ThermoJet
must be running so that the controller can learn the process which the
ThermoJet
is operating. The flashing should last for several minutes but the length
of time will vary per application. Once the flashing stops, the temperature controller
should have adjusted the temperature values and the temperature should return to
normal level.
D.
Verify that the temperature the controller is reading from the
thermocouple is accurate. A method of accomplishing this might be to remove the
thermocouple that is in the
ThermoJet
and attempt to read ambient condition or a
known temperature. Then verify that the temperature reading being displayed by the
temperature controller would match the temperature of the ambient or known
condition. If the two temperatures do not match, then either the temperature
controller or the thermocouple may need to be replaced.
E.
If all of the above are correct, then check the heater resistance, the
heater contactor, the temperature controller contactor, and the pressure switch for
possible malfunction.
High Oil Temperature
A. Verify that oil is flowing normally through the inlet sight glass and that the
pressures of the system are normal.
B. Verify that the temperature controller is set at the desired operating temperature.
The parameters of the PID temperature controller may have drifted and need to be
readjusted. To adjust the parameters of the temperature controller, initiate the auto-
tune function of the controller. To initiate the auto-tune function, depress the up
arrow and the down arrow keys at the same time for longer than 4 seconds. After the
up key and the down key are released, the process value should start flashing. This
flashing indicates that the auto-tune function of the temperature controller has been
started. The flashing should last for several minutes but the length of time will vary
per application. Once the flashing stops, the temperature controller should have
adjusted the temperature values and the temperature should return to a normal level.
C. Verify that the heater contactor is neither stuck, nor has failed in the energized
position. If so, replace the contactor.
