Mitsubishi Electric PQHY-P72ZLMU-A Service Handbook page 370

[ IX Troubleshooting ]
2) Remove all wiring from the unit to the control box,
and remove the control box from the unit.
<Front>
1) Remove the front (service) panel and
the water pipe inlet/outlet panel.
After removing the right panel (R), hang the beam of the INVERTER HEX assembly from the four-way valve piping to keep the
INVERTER HEX assembly from falling downward, using a wire (see the right figure below).
Remove the duct and the solenoid valve block support.
Hang the solenoid valve block from the four-way valve to keep the solenoid valve block from falling downward,
using a wire (see the right figure below).
Unbraze the pipe, remove the pipe assembly (header assembly) (see the left figure below), and remove the water heat exchanger
fixing screws.
Pull out the water heat exchanger.
Fixing screws (2 places)
Install the replacement water heat exchanger.
Reinstall the water heat exchanger fixing screws, solenoid valve block support, and duct as they were.
HWE15150
6) Remove the top panel.
7) Remove the frame FU at above the
control box and on the rear at the top.
3) Remove the frame M at the
bottom of the control box.
INVERTER HEX assembly Beam
Duct
Solenoid valve
block
Solenoid valve
block support
Unbraze here. Unbraze here.
Fixing screw
- 361 -
8) Remove the right panel (R). 5) Remove the frame MB on the
Hang the solenoid valve block with a wire.
Unbraze here.
Fixing screw
4) Remove the rear panel.
<Rear>
back in the middle of the unit.
Four-way valve
Fixing screws
(2 places)
GB