THERMOJET
®
H-2000E SERIES
OIL PURIFIER SYSTEM
INSTALLATION AND OPERATING MANUAL
Doc #
77740121
Rev
15
Date
June 2020
Page
65
of
102
Verify Oil Heater High Temperature Cutout Operation
To perform this maintenance task, the ThermoJet Oil Purifier must be running and operating
normally. This maintenance task is performed to ensure safe operation should a high temperature
condition occur. For additional information regarding the operation of the high temperature circuit
see drawings and schematics in section of this manual titled IX PARTS LIST / DRAWINGS /
SCHEMATICS.
The oil heater is equipped a thermocouples for high temperature protection. The thermocouple is
clamped to the outside of the heater vessel. This thermocouple provides a signal for a high
temperature alarm and cutout for the heater vessel surface.
Should the heater vessel surface thermocouple output reach the high temperature alarm/heater
cutout setting, power to the oil heater element is interrupted. When this happens the oil
temperature as indicated on the heater controller display will begin to decrease. As the oil
temperature falls below oil heater controller setting, the heater control thermocouple will sense
the decreasing oil temperature and signal the oil heater temperature controller to energize the
heater. However the high limit controller will prohibit the oil heater from energizing and oil
temperature will continue to fall. The Heater On pilot light will be illuminated because the heater
controller is providing an ON signal to the heater power control relay.
NOTICE:
When a Heater High Temperature alarm occurs the red
pilot light will illuminate. The alarm pilot light will remain
illuminated and the oil heater will not be operable until the
Heater High Temperature reset button is depressed. Press
the reset push button to resume heater operation.
High temperature pilot light (red)
/ manual high limit reset
T/C clamped to outside of heater
vessel
Heater ON pilot light (amber)
