Drain Level Control System Abnormality - Daikin 4MXL-T Series Service Manual

SiUS121827E
6.2

Drain Level Control System Abnormality

A3
Error Code
Method of Error The float switch detects error.
Detection
Error Decision When the water level reaches its upper limit and when the float switch turns OFF
Conditions
Supposed
 Defective drain pump
Causes  Improper drain piping work
 Clogged drain piping
 Defective float switch
 Defective indoor unit PCB
 Defective short circuit connector X15A, X25A on indoor unit PCB
Troubleshooting
Part 6 Service Diagnosis
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Is the drain
pump connected to X25A on
the indoor unit
PCB?
YES
Does the drain
pump work after the power
supply is on?
YES
Is the drain water level
abnormally high?
NO
Is the float switch
connected to X15A?
YES
Remove the float switch from
X15A, short circuit X15A, and
restart operation.
A3
Does
appear on the remote
controller display?
YES
NO
NO
Is the voltage of
connector X25A 13 VDC?
YES
YES
NO
NO
Troubleshooting for SA Indoor Unit
Connect the drain pump.
NO
Replace the indoor unit
PCB (control PCB).
Replace the drain pump.
There is a drain system
abnormality.
Connect the float switch.
Replace the float switch.
Replace the indoor unit
PCB (control PCB).
(R25079)
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