Panasonic U-4LE1E5 Service Manual

Also see for U-4LE1E5: Installation instructions Service manual Installation instructions Service manual Operating instructions

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Panasonic U-4LE1E5 Service Manual Manual pdf 42 page image

2 - 142Mini VRF SYSTEMOutdoor Unit Repair Procedures(1)(2)(a) Compressor(b) Unit(1)(2)(3)(4)(5)(6)7-1. Compressor Trouble Diagnosis and Check MethodsGenerally, compressor failures can be classified into the following categories.Mechanical troubleElectrical trouble(A) Locking (intrusion of foreign objects, galling, etc.)(B) Pressure rise failure (damaged valve, seal, bearing, or other component)(C) Noise (damaged stator, rotor, valve, or other component)(A) Coil burning(B) Open circuit(C) Insulation failure(D) Short circuitFailure diagnosis is based on the following remote controller displays: [H01], [H02], [H03] (Compressor : right sidewhen viewed from front). A judgment is made based on factors that include the following: coil resistance (variesdepending on the compressor), insulation resistance, current, leakage breaker operation, oil and refrigerant fouling,odor, pressure, and noise.Reference: Insulation resistance (Use a DC 500 V insulation resistance meter and measure the insulationresistance between the electrified and non-electrified parts.)Reference: Symptoms of motor burning1. Ground fault results in breaker operation.2. Short circuit results in different coil resistance at different phases.3. Open circuit7-2. Compressor ReplacementFollow the instructions in “7-4. Replacing the Compressor” and replace compressor in the failed unit.Fully close the high- and low-pressure gauge valves on the manifold gauge, then stop the vacuum pump.Disconnect the manifold gauge from the vacuum pump. Connect the manifold gauge to the refrigerantcylinder. At this time, be careful that air does not enter the refrigerant tubing.Do not use the recovered refrigerant. Use a refrigerant cylinder that containsnew refrigerant.Open the valve on the refrigerant cylinder. When charging with the amount of recovered refrigerant iscompleted, or when charging with the amount of recovered refrigerant is not completed but no morerefrigerant will enter the unit, first turn the power OFF at the repaired outdoor unit, then remove the shortcircuit at the AP pin (CN-AP). Then fully open all valves on the gas tube, and liquid tube.If charging with the amount of recovered refrigerant was not possible, fully close the high-pressure gaugevalve on the manifold gauge. Then, while the unit is operating in Cooling mode, open the low-pressuregauge valve on the manifold gauge and charge with the designated amount of refrigerant.When charging with liquid refrigerant, add refrigerant a little at a time in orderto prevent liquid back-flow.Remove the manifold gauge.* Minimum insulation resistance as required by generally accepted requirements is 1 M .Min. 50 M (servicing part)Min. 10 M (This is due to the presence of refrigerant, which decreasesthe insulation resistance.)CAUTIONCAUTION7. Compressor