How To Remove The Flow Sensor; How To Remove The Booster Heater - Mitsubishi Electric EHST17D-VM2D Service Manual

DISASSEMBLY PROCEDURE

7. How to remove the flow sensor

(1) Remove the front panel. (Refer to Procedure 1.)
(2) Disconnect the CN1A connector on the controller board.
(Photo 4-2)
(3) Release the flow sensor lead wire from the fastener and
the cable strap in the control box, and the cable strap,
the fastener and the band below the control box. (Photos
4-1 and 10-1)
(4) Close (OFF) the strainer valve. (Photo 5-1)
• When the strainer valve handle is stiff, use a tool to grip
the handle and turn it carefully.
• When opening or closing the strainer valve, ensure to do
so fully, not halfway.
(5) Remove the flow sensor by detaching the same diameter
quick connection. (Photos 7-1 and 7-2)
• When reinstalling the flow sensor, use new O-rings.
(Photos 7-1 and 7-2)
• Refer to Procedure 25 for how to attach and detach the
quick connection.
Note: Set the flow sensor in the direction of the arrow print-
ed on the flow sensor, and in the way that the sensor
part faces to the left. (Photo 7-1)

8. How to remove the booster heater

(1) Remove the front panel. (Refer to Procedure 1.)
(2) Disconnect the CNBHT connector on the controller
board, and the booster heater lead wires wired to the
BHC1 (Lead wire No.1, No.2 and No.3) and BHC2
(Lead wire No.4, No.5 and No.6) contactors respectively
and release the lead wires from the fastener, the cable
strap, and the band. (Photos 8-1 and 10-1)
Note: Do not mix up the lead wire numbers when
re-connecting the lead wires to the contactors as the
lead wire numbers are different depending on the
models.
Model
EHST20D-VM6D
EHST30D-VM6ED
EHST20C-VM6D
EHST30C-VM6ED
EHPT17X-VM6D
EHPT20X-VM6D
ERPT20X-VM6D
EHST20D-YM9D
EHST20D-YM9ED
EHST20D-TM9D
EHST30D-YM9ED
EHST30D-TM9ED
EHST20C-YM9D
EHST20C-YM9ED
EHST20C-TM9D
EHST30C-YM9ED
EHST30C-TM9ED
EHPT17X-YM9D
EHPT20X-YM9D
EHPT20X-YM9ED
EHPT20X-TM9D
EHPT30X-YM9ED
EHST17D-VM2D
ERST17D-VM2D
EHST20D-VM2D
ERST20D-VM2D
ERST30D-VM2ED
EHST20C-VM2D
ERST20C-VM2D
ERST30C-VM2ED
EHPT17X-VM2D
ERPT17X-VM2D
ERPT20X-VM2D
ERPT30X-VM2ED
Refer to 6. WIRING DIAGRAM
OCH714A
Lead wire No. Contactor
No.1 BHC1-U
No.2 BHC1-V
No.4 BHC2-U
No.5 BHC2-V
No.1 BHC1-U
No.2 BHC1-V
No.3 BHC1-W
No.4 BHC2-U
No.5 BHC2-V
No.6 BHC2-W
No.1 BHC1-U
No.2 BHC1-V
PHOTOS/ FIGURES
Photo 7-1
Flow direction
Photo 7-2
Photo 8-1
Controller board
Cable straps
Note: The photos shown are of the EHST20C-VM6D model.
70
Same diameter
quick connection
O-ring
Flow sensor
Sensor part
Same diameter
quick connection
O-ring
Lead wire
O-rings
Control box
BHC1
BHC2
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