Emicon RAH - Troubleshooting

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___________________________________RAH / PAH Ka_________________________________
5.3 TROUBLESHOOTING
The detection of the failures occurring during the operation is made by the microprocessor, which besides signalling alarms, also shows the active failure kind.
The hereafter table reports the most common miss-functioning, and for each one the most common causes and possible solutions.
In case of alarm, before any intervention, verify that:
• Working conditions are the expected ones, and in any case, compatible with the unit working limits;
• All electrical cables of the involved components are rmly connected to their terminals (refer to the enclosed wiring diagram);
• The set values for the involved parameters are compatible with the real working conditions (refer to the enclosed microprocessor handbook).
Contactors used to activate electrical loads must be inspected to check their integrity, contacts condition and the coil functionality. Also verify that the electrical
cables are correctly and rmly tighten to their terminals. If required, remove any dust or waste which can cause a noisy and unreliable operation of the device.
FAILURE PROBABLE CAUSE SUGGESTED ACTIONS
1. Unit is not working
a) electrical board is not power supplied.
Check each phase Voltage in the power supply line
Check that main Switch is closed (position ON)
b) Auxiliary circuit is not power supplied
Check the fuses of the auxiliary circuit (see wiring
diagram)
c) Microprocessor does not start the unit
Check microprocessor electrical connections
Check temperature set value
d)External consent to the unit start is missing
Check that the remote ON/OFF contact is
closed (see wiring diagram)
Enable consent to the unit start from user board
(display)
2. High pressure switch is
activated
a) The condensation pressure control system (if
present) is not efcient
Check calibration and functionality of the
condensation pressure control system.
b) One or more condensing fans are out of order
Check if the internal thermal protection of non
functioning fan(s) has been activated; replace
broken fans
c) Not calibrated high pressure switch Replace High Pressure Switch
d) Too high discharge pressure See point 8
e) Condensation water ow is not enough
Check that all the valves are correctly positioned
Check that there is no air in the circuit
3. Low pressure switch
activation
a) Low pressure switch is not calibrated Replace low pressure switch
b) Too low suction pressure See point 7
4. Compressor is not working
a) Automatic switch intervention Reset the Switch, check the short circuit pause
b) Compressor internal protection activation
Check the heater of compressor internal windings.
Once reset, measures voltage and absorption.
Check that the working parameters fall within nominal
values
c) Contactor does not work Verify contactor contacts and coil.