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20
DIAGNOSTIC CHARTS (CONT.)
Check heat sink for
obstruction and dirt
Check if connection
is loose
Check voltage and current.
Ok? See note below **
No
Check voltage and balance
between any two phases of
U,V, and W. Ok?
* Remove screws, remove heat sink, remove thermal grease. Apply new thermal grease and reassemble.
** Check if voltage between power module P and N is too low and if current is too high. In normal conditions,
voltage between P and N should be about 370V.
Clean.
Problem fixed?
Yes
See note below *
Is problem fixed?
Yes
No
No
Measure voltage between
X15 and X9. Ok?
No
Replace capacitor.
Problem fixed?
Yes
No
No
Replace outdoor board
Replace compressor
No
Check heat sink for
obstruction and dirt
Check if connection
is loose
Check voltage and current.
Ok? See note below **
No
Check voltage and balance
between any two phases of
U,V, and W. Ok?
* Remove screws, remove heat sink, remove thermal grease. Apply new thermal grease and reassemble.
** Check if voltage between power module P and N is too low and if current is too high. In normal conditions,
voltage between P and N should be about 370V.
Clean.
Problem fixed?
Yes
See note below *
Is problem fixed?
Yes
No
No
Measure voltage between
X15 and X9. Ok?
No
Replace capacitor.
Problem fixed?
Yes
No
No
Replace outdoor board
Replace compressor
No
A09366
Fig. 34 – IPM Module Protection
Yes
Start unit using remote
control. Audible noise heard?
Unit started?
Try to start unit using auto
Function. Unit runs?
Use auto function to
shut off unit.
Problem solved
Check batteries. OK?
Replace battery
Go to chart 13
Reset circuit breaker. Is unit
running?
Yes
Problem solved
Is there power to outdoor
unit?
Yes
Check input and output on
outdoor board. Ok?
Check components. Ok?
Flow charts 10 thru 12
No
Replace defective
component
Check wiring and circuit
breaker and fix
Replace outdoor board
Check fuse on indoor
board. Ok?*
Replace fuse
Determine defective
component and replace
Yes
Yes
Yes
No
No
No
No
No
No
No
No
Yes
Yes
Replace indoor board
Check input and output on
indoor board. Ok?
Yes
Yes
Start unit using remote
control. Audible noise heard?
Unit started?
Try to start unit using auto
Function. Unit runs?
Use auto function to
shut off unit.
Problem solved
Check batteries. OK?
Replace battery
Go to chart 13
Reset circuit breaker. Is unit
running?
Yes
Problem solved
Is there power to outdoor
unit?
Yes
Check input and output on
outdoor board. Ok?
Check components. Ok?
Flow charts 10 thru 12
No
Replace defective
component
Check wiring and circuit
breaker and fix
Replace outdoor board
Check fuse on indoor
board. Ok?*
Replace fuse
Determine defective
component and replace
Yes
Yes
Yes
No
No
No
No
No
No
No
No
Yes
Yes
Replace indoor board
Check input and output on
indoor board. Ok?
Yes
A09367
Fig. 35 – Unit Not Running, No Diagnostic Code
38/
40GX
C
(Q
)