Mitsubishi Electric HP120TNU-A Service Handbook page 339

[8-14 BC Controller Maintenance Instructions ]
3. Removing the drain pan
Work procedure
1) Remove the fixing screw on the long side of the bottom
panel.
(Four places encircled by circles in Figure 1)
2) To prevent the bottom panel from falling, of the four
screws indicated with triangles in Figure 1, only loosen
(but not remove) the two screws that are diagonally lo-
cated or on the opposite ends of the long side of the pan-
el (either (1) and (3), (2) and (4), (1) and (4), or (2) and
(3)). Remove the two remaining screws.
3) As shown in the enlarged view of Figure 1, the fastening
screw hole on the short side looks like two circles in dif-
ferent shape joined together (double-snowman shape).
Slide the bottom panel in the direction of the arrow, and
remove it in the downward direction. (Figure 2)
4) When removing the drain pan, hold the protruded area
of the panel or the socket and pull it straight down, using
caution not to let it come into contact with the sheet met-
al. (Figure 3) If the drain pan comes into contact with the
sheet metal, the drain pan may be scraped, leading to
water leakage.
Installing the bottom panel
1) Of the four screws indicated with triangles in Figure 1,
partially tighten the two screws that are diagonally locat-
ed (either (1) and (3), or (2) and (4)).
2) Thread the screw into the double-snowman shaped
hole, move the panel in the opposite direction as when
it was removed in step 3) above, set the screw into the
smaller circle, and tighten the screw to hold the panel in
place.
3) Tighten the remaining screws.
Do not stay directly underneath the unit when working
with the bottom plate. Remove the drain piping to re-
move the drain pan. Check that no water has accumu-
lated in the drain pan.
4. Thermistor (liquid pipe/gas pipe temperature detection)
Work procedure
(1) Remove the service panel.
1) See the right figure and the section [3-5 External Ap-
pearance and Refrigerant Circuit Components of BC
Controller] for information on TH11, TH12, TH15, and
TH16.
(2) Remove the lead wire of the piping sensor
from the control board.
1) TH11,TH12 (CN10)
2) TH15,TH16 (CN11)
(3) Pull out the temperature sensor from the
temperature sensor housing, and replace
the temperature sensor with the new one.
(4) Connect the lead wire of the temperature
sensor securely on the control board.
98
- chapter 8
Explanatory figure
(2)
(1)
Bottom panel
(Figure 1)
(Figure 2)
Protrusion
(Figure 3)
*Special care must be taken when replacing heavy parts.
Explanatory figure
TH11
CMB-P1016NU-KA1
(3)
Slide direction
(4)
(Enlarged view of
Figure 1)
Socket
Drain pan
TH16
TH12
TH15
HWE18220_GB