Amron 9000-ECS, User Manual

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MODEL 9000-ECS USER MANUAL
9000-ECS-UM REV 4.0
11
7. MAINTENANCE AND TROUBLESHOOTING
GENERAL 7.1
Trained personnel should perform maintenance. A refrigeration technician should be used
for any servicing of the refrigeration system. An electrician can service the electrical system.
The balance of the system can most likely be serviced by either.
To gain access to the system, remove the side covers by removing the screws at the bottom
of the panels. After removing the screws on the side, slide the panels downward and
remove. To charge the system with Freon, remove both front and rear panels. The suction
service valve is located on the front side, on compressor. The discharge service valve is
located on the rear side, on the accumulator.
To charge or check Freon pressure, remove service valve covers, attach refrigerant gauges,
crack service valves. To add Freon, attach Freon bottle and use standard charging
procedures.
To check or set the high temperature limit controller, operate the unit in the heat mode with
the chamber internal conditioning unit shut off. Monitor supply thermometer on front panel or
place a calibrated thermometer in the reservoir and monitor the fluid temperature. Unit
should shut off at approximately 110
o
F. If unit does not shut off at the correct temperature
adjust the high temperature limit controller, (located on the upper level, front left side of the
reservoir). An easy way to adjust the controller is to note the present setting of the controller
and the point at which the heater did shut off and adjust accordingly. Example: The unit shut
off at 100
o
F and the controller is set at 105
o
F, the difference between the actual and the
desired is 10
o
F, therefore it will be necessary to raise the actual set point by 10
o
F. Set
temperature controller to 115
o
F and check the results.
The low temperature limit controller is set in the same manner. Allow the unit to operate until
the compressor shuts off and check the temperature. Adjust the controller, heat the unit up
slightly and run another test to check the set point.
The cool circuit has a second controller to stop the system in the event of loss of Freon. This
is the low-pressure controller mounted on top of the compressor electrical junction box. This
controller will also act as a low limit controller.
To adjust the time delay for the compressor, remove the cover from the electrical control
box. NOTE: Removing the cover exposes voltages that are hazards to life, this should only
be attempted by personnel qualified to work on electrical equipment. The time delay is
located in the upper left corner of the box.
Turn clockwise to increase delay time. Check by starting a cycle and timing the time for the
cool contactor to pull in.
To check internal fuses, disconnect power from system, remove cover from power control
box, remove fuses one at a time and check continuity. Replace blown fuses with fuse of
same value. If fuse blows a second time remove power and determine cause.