Panasonic Urban Multi MX1R Series, Service Manual, Page: 367 / 643

Troubleshooting PACD011001C2
346 Troubleshooting Urban Multi “MX1R, ME1R Series” Using R-407C
3.3 Indoor Unit: Malfunction of Drain Level Control System (33H)
Remote Controller
Display
A3 A3 A3 A3
Supposed Causes
„
Defect of float switch or short circuit connector
„
Defect of drain pump
„
Drain clogging, upward slope, etc.
„
Defect of indoor unit PC board
„
Loose connection of connector
Troubleshooting
(VF030)
Replace float switch
Modify the float switch's connection
and turn on again.
Connect the drain pump and turn on
again.
Check the drain piping for clogging or
upward slope, etc.
Replace indoor unit PC board.
Replace the drain pump or check for
dirt, etc.
Connect either a short circuit
connector or float switch and turn on
again.
YES
YES
YES
YES
Defect of indoor unit PC board
Loose connection of connector
NO NO
NO
YES
YES
NO
NO
YES
NO
YES
NO
NO
The float
switch is connected to
X18A of the indoor unit
PC board.
NO
The drain
pump works when
the power supply is reset
for the indoor unit.
The drain
pump is connected to
X25A or terminals X8S
and X9S of the indoor
unit PC board.
The voltage
of terminals Y1 and Y2 or
X25A is 220~240 V (within 5
minutes of resetting
the power supply).
Water builds up
in the drain pan.
The float
switch contact is
forming a short circuit
(continuity check with
X18A disconnected)
A short
circuit connector is
connected to X18A.
Becomes
normal when X18A of
the indoor unit PC board
is short circuited
The float switch
functions normally.
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.