Guidelines For Maintenance And Inspection Of Major Parts - Mitsubishi Electric CAHV-R450YA-HPB Service Manual

[ IX Maintenance ]

[2] Guidelines for Maintenance and Inspection of Major Parts

Troubleshooting according to the remote controller malfunction or the external inpu t error
Both for MA remote con troller and ME remote controller
The table below shows regular inspection items, schedule, and parts replacement criteria under normal use condition. The "Inspection schedule" column under the "Preventive maintenance"
column indicates the regular inspection schedule, and the "Maintenance schedule" column indicates an estimation of the time when the parts need to be cleaned or adjusted or when old parts need to
be replaced or repaired. The cleaning/adjustment schedule is provided in order to take proper measure to protect the parts from deterioration or performance drop, and the estimated
operating time or use period when each part goes into the wear-out failure period is provided so that replacement of the parts can be made at the right timing after the inspection.
Parts name
Component
Parts name
parts
Refrigerant
circuit
Compressor
Electronic
expansion valve
Inner piping
Refrigerant
system
Solenoid valve,
4-way valve
Container
High-voltage circuit
Protection
breaker
device
(security
parts)
Fusible plug
Air side
Heat
exchanger
Water side
Electrical/
Fan motor
Electronic parts
Cooling fan
Electromagnetic
Switch
switch
(including
Overcurrent relay
FFB and ELB)
Auxiliary relay
Thermostat
Oil heater
Crankcase heater
Fuse
Control box
(including inverter)
Electrolytic capacitor
Smoothing
capacitor
Electric parts box
(including circuit board)
Pressure sensor, thermistor
SW power source
Structural
Decorative part (design part)
parts
Frame, bottom plate
Propeller fan
Drain pan
Guard panel
Optional parts
Remote controller switch
Central control system
Flow switch
Phase-advanced condenser
Elapsed time integrator Ammeter
Water circuit
Strainer
Water pipe
Flow regulating valve
Pump
Pressure gauge
Thermometer
Water
Note1) Unexpected failure is a sudden and unpredictable failure that occurs randomly before the parts or the device reaches its lifespan. It is difficult to take the technical measures, and at the moment where only the measures based on
statistics can be taken.
Note2) The elapsed year shown in the column marked with * is the estimated period of time under the condition the equipment use
the operating condition. Confirm the details whenever conclude the maintenance contract.
Note3) shows the estimated the year of initial wear-out happen and increase of failure rate year by year.
HWE22020
Inspection item Inspection method/tools
• Sound or vibration at startup, during Visual, auditory, and tactile
operation, and at stoppage of the check
compressor 500V megahertz
• Insulation resistance Screwdriver, visual check
• Terminals and wiring
• Operation Tactile check
• Operating sound by turning ON or OFF Auditory and tactile check
the unit (pressure check)
• Sympathetic vibration, contact, and Visual check
corrosion of the inner piping
• Sympathetic vibration and contact of Visual check
the capillary tube
• Operation and insulation performance of 500V megahertz
the solenoid valve and the 4-way valve
• Corrosion and abnormal sound Visual and auditory check
• Corrosion of the accumulator or the oil
separator
• Operating pressure, refrigerant leak, Pressure gauge etc.
and insulation resistance
• Appearance Visual check
(swollen soluble metal)
• Clogging and damage Visual check
• Refrigerant leak Refrigerant leak detector
• Amount of water, temperature • Thermometer, flowmeter and
• Refrigerant leak differential pressure gauge
• Drain • Refrigerant leak detector
• Check the heat exchanger
and the inside the pipe.
• Abnormal sound
Auditory check
• Insulation resistance
500V megahertz
• Insulation resistance and abnormal 500V megahertz,
sound auditory check
• Operation and appearance Visual check
• Contact points
• Operation check • Operation by the unit
• Check energization • Tester or ammeter
• Insulation resistance • Visual check
• 500V megahertz
• Whether the crankcase heater is Tester
powered during compressor stop
• Insulation resistance of the crankcase 500V megahertz
heater
• Appearance Visual check
• Insulation resistance or the circuit 500V megahertz
• Dust of the circuit board Visual check
• Terminals and connectors Screwdriver, visual check
• Appearance of the electrolytic capacitor Visual check
• Capacitance and insulation resistance Electrostatic meter,
500V megahertz
• Insulation resistance of the circuit and 500V megahertz
appearance of the capacitor
• Terminals and connectors Visual check
• Self-diagnosis mode and appearance Visual check
• Open, short-circuit, Tester, visual check
and appearance
• Output voltage Tester
• Dirt and damage Visual check
• Rust and insulation material Visual check
• Flaked coating
Visual check
• Vibration and appearance
• Check the drain for clogging. Visual check Visual check
• Check for peeling paint.
• Flaked coating
Visual check
• Controllability Visual check
• Controllability • Visual check
• Loose terminal, wiring contact • 500V megahertz
• Insulation resistance
• Controllability • Visual check
• Water leak check • 500V megahertz
• Insulation resistance
• Insulation resistance • 500V megahertz
• Check clogging • Visual check
• Water leak • Visual check
• Inclusion of air • Sensory inspection/Air vent
valve is open
• Water temperature difference (flow rate) • Thermometer
• Vibration • Visual/audibility/tactile
• Insulation resistance impression check
• Water leak check • 500V megahertz
• Loose terminal, wiring contact • Visual check
• Clean and inspect the strainer
• Display value under suspension • Visual check
• Display value under suspension • Surface thermometer
• Water quality management • Water quality analysis
Regular inspection
Judgement criteria <Reference>
• Free from abnormal noise and vibration
• The insulation resistance is 1Mohm or greater.
• Free from loose terminals and wiring contacts
• Refrigerant circulation is confirmed.
• Operating sound is heard and temperature change
is confirmed.
• Free from abnormal sympathetic vibration, sound,
and corrosion
• Free from abnormal sympathetic vibration and
contact wear
• The insulation resistance is 1Mohm or greater. • The insulation resistance is 1Mohm or greater.
• Free from abnormal noise and corrosion
• Free from corrosion
• The high-voltage circuit breaker operates at the set
value.
• The measured value is within the range specified
by the regulation.
• The soluble metal is at the normal position.
• Free from clogging and damage
• Free from leakage
• Tolerance
• Free from leakage
• Installation
• Free from abnormal noise
• The insulation resistance is 1Mohm or greater.
Free from abnormal sound
• Free from deformation
• Normal operation and free from deformation
• Free from deformation and discoloration
• Operation as per the technical document
• Heat up
• More than 1Mohm
• The insulation resistance is 1Mohm or greater.
compressor stop, and is heated up.
• The crankcase heater is powered during
• Free from deformation and
discoloration
• The insulation resistance is 1Mohm or greater.
• Free from accumulation of dust
• All connectors are properly connected.
• Free from liquid leak and deformation
• At or over the specified value
• The insulation resistance is 1Mohm or greater.
• All connectors are properly connected.
• No error display appears.
• Within the specified value, and free from
discoloration
• Within the specified output voltage range
• Free from dirt, damage, and deformation
• Free from rust and damaged insulation
• Free from runout and matter biting
• Free from drain clogging
• Free from rust and holes
• Free from rust
• The display obeys the operation command.
• The display obeys the operation command
• Free from loose and contact
• More than 1Mohm
• The display obeys the operation command
• More than 1Mohm
• More than 1Mohm
• Free from stain and clogging
• Free from water leak
• Free from strange noise
• Proper temperature difference range
• Free from strange noise
• More than 1Mohm
• Free from loose and contact
• Free from water leak
• Free from clogging
• Free from incorrect display value
• Free from incorrect display value
• Water quality criterion
d 10 hours per day and for 2500 hours per year without frequent start and stop. The years vary depending on
- 122 -
Preventive maintenance
Maintenance item
• If abnormal, replace the compressor.
• If the insulation resistance is 1Mohm or less, replace
the compressor.
• Retighten the terminals, and rewire the wiring.
• Replace the electronic expansion valve if it is stuck.
• If the pipes are severely corroded, replace or repair the
pipe.
• If the pipes are severely worn out, replace or repair the
pipe.
• If the insulation resistance is 1Mohm or less, replace
the valve.
• If there is corrosion, paint the surface.
• Replace the parts regularly.
• Clean the air inlet if clogged.
• If the refrigerant leak is detected, repair or replace the
heat exchanger
• Adjust the valve and operation setting
• If the refrigerant leak is detected, repair or replace the
heat exchanger
• Add the drain valve
• If the bearing sound is loud, replace the bearing.
• If the insulation erodes, replace the motor.
• Replace the cooling fan if the fan is stuck.
• Replace the switches in case of malfunction,
deformation, or discoloration.
• Replace or adjust (calibration)
• Replace
• Rewire the electric wiring.
• If the insulation resistance is 1Mohm or less, replace
the crankcase heater.
• Replace the fuse if the fuse is blown.
• If tainted with a large amount of dust, clean with a brush.
• Replace the circuit board in case of malfunction.
• Retighten the terminals, and reconnect the connectors.
• Replace the electrolytic capacitor in case of liquid leak.
• Replace the capacitor regularly.
• Replace the circuit board in case of malfunction.
• Retighten the terminals, and reconnect the connectors.
• Replace the circuit board in case of liquid leak.
• If the wire is disconnected or short-circuit, replace the
pressure sensor or the thermistor.
• Replace the SW if the voltage is abnormal.
• Wash the panel with neutral detergent, and paint the surface.
• Repair the frame or the bottom plate if the insulation material is torn.
• Paint the surface.
• Replace the propeller fan if the runout and balance is
significantly worse
• Clean the drain pan and check tilt
• Repair painting
• Paint the surface.
• Replace the remote controller switch if the display does not
obey the operation command or wrong display appears.
• Retightening
• Replace If the resistance is less than 1Mohm
• Replace the flow switch
• Replace If the resistance is less than 1Mohm
• Clean
• Retightening
• Release air, or replace and adjust the air vent vane.
• Replace and adjust
• Replace
• Retightening
• Modify the wiring
• Replace
• Replace
• Adjust water quality
GB