Finish Thompson BE-55C - Manual (Page 16)

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PROBLEM: UNIT WILL NOT TURN ON.
Possible Cause 1: No or Improper Electrical Power.
 No power to the unit, check main circuit breaker. If tripped, verify correct wiring and electrical
supply to the BE unit (see pg. 6 for electrical connections).
 Verify that the LED on the phase control relay is illuminated. If not, interchange any two of the three
phase wires.
 Unit has not cooled down sufficiently from the previous batch. Allow unit to cool.
If the wiring to the unit is as above and correct, refer to the “Problem: Circuit breaker keeps tripping” in
the “Troubleshooting Tests and Repairs” section of this manual.
Possible cause 2: Safety overtemp sensor(s) activated
CAUTION: Disconnect electrical power to the BE unit at the main breaker before performing
tests on the temperature activated Switches (TAS)
Check TAS2 for continuity. This is a “normally closed” switch, threaded into the front of the process
tank behind the heaters covers. It is a 1/2” diameter white ceramic sensor with a brass hex base and
two wires (#1L1 and #10) connected to it. Check for continuity between these wires. See “Parts
Location Diagram” on page 36.
 If
there is continuity between the two terminals of TAS2, the switch is O.K.
 If there is not continuity between the two terminals of TAS2, the sensor has tripped.
These units’s use a switch rated for 385ºF. This will be indicated by “L385” written on the sensor. This
sensor should reset at 285ºF. If the process tank is cool and this sensor has not reset, then replace
TAS2.
If TAS2 has tripped, this indicates that the process tank is overheating. This can occur if there is a
residue build-up in the tank, or if the low-level control system does not turn off the unit with 5-7 gallons
of liquid left in the Process Tank. Perform a “detergent flush” and check the low-level control system.
See “Low Level Control Probe is shorted to ground” on page 26.
Check TAS4 for continuity. This is a “normally closed” switch threaded into the Distillate Piping between
the Condenser and the Divert Solenoid Valve. It is a 1/2” diameter white ceramic sensor with a brass
hex base and two wires (#18A and #18) connected to it. See “Parts Location Diagram” on page 36.
 If
there is continuity between the two terminals of TAS4, the switch is O.K.
 If there is not continuity between the two terminals of TAS4, the sensor has tripped.
TAS4 is a switch rated for 180ºF. This will be indicated by “L180” written on the sensor. This sensor
should reset at 100ºF. If TAS4 has tripped, this indicates that the Distillate Piping has overheated. One
way this can occur is if the operator attempts to fill the Process Tank when the unit is still hot. The
uncooled steam created can trip TAS4, which will prevent the unit’s heaters from turning on (fans will
still run and the Autofill switch (SW2) will be illuminated in the off position). If the unit is cool TAS4
should have reset, if it has not reset, TAS4 is defective and must be replaced.