Mitsubishi Electric EHST17D-VM2D Service Manual page 79

DISASSEMBLY PROCEDURE
18. How to remove the plate heat exchanger (P-HEX)
<Water - Water>
(1) Remove the front panel. (Refer to Procedure 1.)
(2) Drain water in the P-HEX (Water-Water) using the drain
cock (Primary circuit) and the drain cock (Sanitary
circuit). (Photo 18-1)
(3) Remove the 2 screws to remove the water coil W cover.
(Photo 18-1)
• Reuse the water coil W cover and the fixing screws.
(4) Remove the 4 G3/4" nuts.
• When reinstalling the nuts, use new G3/4" gaskets.
(5) Remove the P-HEX (Water-Water). (Photo 18-2)
(6) Remove the drain cock (sanitary circuit). (Photo 18-1)
• When reinstalling the drain cock
• When reinstalling the drain cock (sanitary circuit), use a
new one.
Photo 18-2
P-HEX (Water-Water)
19. How to remove the water pump (sanitary circuit)
(1) Remove the front panel. (Refer to Procedure 1.)
(2) Disconnect the CNP4 connector and the earth cable in
the control box. (Photo 4-2)
(3) Release the water pump lead wire from the cable clamp
and the cable strap in the control box, the cable strap,
the fastener and the band below the control box.
(Photos 4-1 and 10-1)
(4) Remove the pipe (tank-
nuts. (Photo 19)
• When reinstalling the G3/4" nuts, use a new G3/4"
gaskets.
(5) Remove the 2 screws to remove the st band.(Photo 19)
(6) Remove the 2 screws to remove the W.P. support.
(Photo 19)
(7) Remove the water pump (sanitary circuit) by removing
the two G1" nuts using the 2 spanners, one to hold the
G1" nut and the other to turn the other side of G1" nut.
(Photo 19)
• When reinstalling the G1" nuts, use a new G1" gaskets.
• Set the water pump in the orientation of the arrow
printed on the water pump and in the way that the
terminal box faces to the left. (Photo 19)
• Set the pump speed of the newly installed water pump
to " ". (Photo 19)
OCH714A
P-HEX (Water-Water)
(inside)
Drain cock
(Primary circuit)
Nut (G3/4")
Gasket (G3/4")
) by remove the 2 G3/4"
W.C.
79
PHOTOS/ FIGURES
Photo 18-1
Gasket (G3/4")
Nut (G3/4")
Photo 19
Pump
speed:
Flow
direction
Terminal
box
Pipe
(tank-W.C.)
W.C.
support
Screw
Nut
(G3/4")
Gasket
(G3/4")
Water
coil W
cover
Drain
cock
(Sanitary
circuit)
Nut
(G3/4")
Gasket
(G3/4")
Screw
Screw
ST Band
Nut (G1")
Gasket (G1")
Water pump
(Sanitary circuit)
W.P. support
Nut (G1")
Gasket (G1")
Nut (G3/4")