Mitsubishi Electric EHGT17D-YM9ED Service Manual page 81

DISASSEMBLY PROCEDURE
5 . How to remove the control box
(1) Remove the front panel. (Refer to Procedure 1.)
(2) Remove the frame. (Refer to Procedure 4-2.)
(3) Disconnect the lead wires connected to the following
controller boards and the CONT base front. (Photo 4-3)
● ATW controller board: CNP4 / CNW5 / CN851
● Controller circuit board: TH7 ● Lead wire: CNP4
(4) Disconnect the relay connectors below. (Photo 4-2).
Connector color Number of pins Applicable parts
White 3
Black 6
White 9
White 16
White 12
White 8
White 10
(5) Release the lead wires (Refer to Procedure 5-3.) from the
wiring part in the control box.
(6) Disconnect the on-site wires from the terminal block and
the breaker in the control box to release the wires from
the wiring part in the control box.
(7) Release the lead wires (Refer to Procedure 5-3.) and on-
site wires from the clamps and the cable straps in the
control box . (Photo 4-2)
(8) Remove the screws fixing the control box and the side
frame (6 screws 4x10). (Photo 5-1)
(9) Disengage the tabs on the left, then pull the control box
and swing it to the right.
(10) Release the lead wires from the clamps on the back side
of the control box. (Photo 5-2)
(11) Disengage the tabs on the right, then remove the control
box from the side frame. (Photo 5-1)
6. How to remove 3-way valve
(1) Remove the front panel. (Refer to Procedure 1.)
(2) Remove the lead wire connected to the 3-way valve.
(Photo 6-3)
(3) Remove the module box front from the module box assy
and the side frame. (12 Hex screws from A to L 5×12)
(Photo 6-1)
(4) Drain and collect water from the drain cock on the water
pump circuit. (Photo 6-2)
(5) Remove the 3-way valve, the 3 fasteners, the 3 O-rings
from the pipes connected to the 3-way valve. (Photo 6-3)
Notes:
1. Use Hex screws 5×12 to fix the module box front. Tighten
the module box front in the order from screw A to L.
Photo 6-1
Hex screws
5×12
E
I
J F
OCH722A
Comp
Reactor
LEV-A / Flow SW / HP SW
Thermistor
Booster heater
Primary side pump (power)
Brine pump
Primary side pump (control)/
Flow sensor/ Pressure sensor
Module box front
A
B
K
G
H L
C D
PHOTOS/ FIGURES
Photo 5-1
Photo 5-2
Photo 6-2
Module unit assy
Photo 6-3
81
Screws 4×10
Tabs on the right
Tabs on the left
Side frame R
Side frame L
Clamp
Clamps
Control box
Water pump
Drain cock
Fasteners
O-rings
Connector
3-way valve
Cable
straps