Inspection And Maintenance - Mitsubishi Electric City Multi PUHY-P-YKB-A1 series Installationshandbuch

12. Inspection and maintenance

Only qualified personnel must relocate or repair the unit. Do not attempt to disassemble or
alter the unit.
- Failure to do so will result in refrigerant leakage, water leakage, serious injury, electric shock, or
fire.
・While the unit is turned on, the compressor will remain energized even when it is stopped. Before inspecting the
inside of the control box, turn off the power, keep the unit off for at least 10 minutes, and confirm that the capacitor
voltage (inverter main circuit) has dropped to 20 VDC or less. (It takes about 10 minutes to discharge electricity
after the power supply is turned off.)
・Control boxes house high-voltage and high-temperature electrical parts. They may still remain energized or hot
after the power is turned off.
・Perform the service after disconnecting the fan board connector (CNINV) and the inverter board connector (CN1).
(To plug or unplug connectors, check that the outdoor unit fan is not rotating and that the voltage of capacitor in the
main circuit is 20 VDC or below. The capacitor may collect a charge and cause an electric shock when the outdoor
unit fan rotates in windy conditions. Refer to the wiring nameplate for details.)
Reconnect the connector (CNINV) back to the fan board and reconnect the connector (CN1) back to the inverter
board after servicing.
・Unit components may be damaged after long use of the unit, resulting in a performance drop or the unit becoming a
safety hazard. To use the unit safely and maximize its life, it is recommended that a maintenance contract with a
dealer or qualified personnel be signed. If the contract is signed, service technicians will periodically inspect the unit
to identify any damage at an early stage, and take appropriate measures.
KD79S703H01
GB-47