This chapter hereto is aimed to help operators performing the unit to analyze causes resulting in the failures and provides them with methods to debug. The controls made to the dehumidifier unit can be designed and modified with convenience based on the requirements to use. In order to favor analyzing the failures, please refer to the circuit diagram and the relevant materials attached to the unit.
There is high voltagse existing inside of the dehumidifier and so that it shall be made certain that the power to the dehumidifier is cut off before any measure is taken up to debug.
There are high-temperature areas (reactivation heating and other heating segments) in the inner of the dehumidifier and thereby no maintenance is allowed to undertake until the unit and pipes connected are all cooled down.
Any operation including adjustment, maintenance and reapir shall be performed by technicians qualified and such relevant personnel shall be definitely aware of the fact that there are high temperature and high voltage existing inside of the dehumidifier.
Should the unit come to failure, please refer to the contents shown as following containing analysis description of such failures and then measures that may be taken to debug prior to contacting the OEM. The table hereinunder does not include any content regarding the exterior parts to the unit and thus please refer to the other relevant materials provided by the OEM for description where necessary.
Symptom |
Possible Causes |
Debugging Measures |
Unit Shutdown |
Power Supply Fault |
Inspection of Power Supply Available to the Unit |
（All indication lights off） |
Transformer of the control wiring fails or fuse of secondary circuit trips . |
Find out the causes resulting in the fault and take up the corresponding debugging. |
Unit Shutdown |
|
Reset the fused switch of line. |
(Indication lights of the unit while the operation |
Manual operating mode: |
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indication lights off.) |
the unit is to shifted to the automatic operating mode(user mode)though), |
unit shifted to the manual operating mode. |
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the unit has not received any exterior operation signal. |
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Resulted from the wrong control wiring inside of the dehumidifier or from |
Inspect and debug the corresponding faults in accordance with the electric |
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parts’faults. |
installation drawing attached to the unit. |
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Automatic operating mode: |
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Faults of exterior control signal. |
Debugging shall be made in accordance with the materials provided by OEM. |
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Resulted from the wrong control wiring inside of the dehumidifier or from |
Inspect and debug the corresponding faults in accordance with the electric |
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parts’faults. |
installation drawing attached to the unit. |
Unit Shutdown |
Fault A: |
|
（Indication lights of the malfunction alarm on and the |
On-off action made to the protection switch （ QM** ）of the electric motor. |
Inspect the electric motor and power supply, inspection made to make sure the |
one of the power supply on.） |
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rotation of the fan flexible. |
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Inspect the air volume to process and reactivate. Inaccuracy of air volume may cause the motor of the fan overloaded. |
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Fault B: |
Inspect flexibility to the rotation of the fan and the drive unit. |
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Motion made to the tripping protection device against the high temperature. |
Inspection made to check any blockage existing in the air pipe of the air inlet/outlet and in the valve. |
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（There are none acailable to the steam heating types.） |
Clear off the dust or off the clogged sundries; open up the air valve. |
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Reset the tripping protection device as the unit cools down. |
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Or other fault signal accessed to based on the control requirements. |
Find out faults and debug by referring to the relevant materials. |
Dehumidifying capacity declines |
Insufficient regenerating heating capacity. |
Inspect the operation conditions of the heater. |
（The dehumidifier is displayed normal though, |
The air volume of the reactivation air or of the process air doesn't meet the design |
Measure and adjust the air volume of the reactivation air or of the process air. |
the humidity stays.） |
requirements to the unit. |
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Rotor-driven system failure. |
Inspect rotor-driven belt and the drive motor. |
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Abnormal operation of the exterior control system(automatic operating mode). |
Inspect the operation conditions of the control system in accordance with the |
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methods recommended by the supplier. |
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air-conditioned air system may possibly be leaked |
Find out the leakage point of the system and take up the sealing again. |
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Insufficient refrigeration capacity available to the heat exchanger(pre- refrigeration) of the dehumidifying system |
Inspect the refrigeration system and the controls. |
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(the temperature of the ice water is excessively high or the flow of it is extremely small). |
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The heat exchanger(pre-cooling) may be dust-clogged. |
Clear the heat exchanger off the dusts or blocked sundries. |
Temperature excessively high at the outlet air of the dehumidifier. |
Insufficient refrigeration capacity available to the heat exchanger(post-refrigeration) of the dehumidifying |
Inspect the refrigeration system and the controls. |
(Temperature requirements expected and set to the |
system(the temperature of the ice water is excessively high or the flow of it is extremely small). |
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dehumidifier,however,the temperature fails to drop). |
The heat exchanger(pre-cooling)may be dust-clogged. |
Clear the heat exchanger off the dusts or blocked sundries. |
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Leakage possibly be existing to the reactivation air. |
Inspect the sealing between the reactivation air and the process air (the |
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radial sealed strips at the either side of the rotor ). |
