FILE NO. SVM-07008

11. HOW TO DIAGNOSE THE TROUBLE

The pulse modulating circuits are mounted to both indoor and outdoor units. Therefore, diagnose troubles according to the diagnosis procedure as described below. (Refer to the check points in servicing written on the wiring diagrams attached to the indoor/outdoor units.)

 

Table 11-1

No.

Troubleshooting Procedure

 

 

1

First Confirmation

 

 

2

Primary Judgment

 

 

3

Judgment by Flashing LED

 

of Indoor Unit

 

 

4

Self-Diagnosis by Remote Control

 

 

5

Judgment of Trouble by

 

Every Symptom

 

 

6

How to Check Simply the Main Parts

 

 

NOTE:

A large-capacity electrolytic capacitor is used in the outdoor unit control (inverter). Therefore, if the power supply is turned off, charge (charging voltage DC280V) remains and discharging takes a lot of time. After turning off the power source, if touching the charging section before discharging, an electrical shock may be caused. Discharge the electrolytic capacitor completely by using soldering iron, etc.

<Discharging method>

(1)Remove the inverter cover (plating) by opening four mounting claws.

(2)As shown below, connect the discharge resistance (approx. 100Ω 40W) or plug of the soldering iron to voltage between + – terminals of the C14

(“CAUTION HIGH VOLTAGE 380 V” is indicated.) electrolytic capacitor (760∝F/400 V) on P.C. board, and then perform discharging.

 

 

Inverter cover

Discharging position

Plug of

P. C. board

soldering

(Soldered surface)

(Discharging period

iron

 

10 seconds or more)

 

 

 

10-1. First Confirmation

10-1-1. Confirmation of power supply

Confirm that the power breaker operates (ON) normally.

Fig. 11-1

10-1-2. Confirmation of power voltage

Confirm that power voltage is AC 220-240 V ± 10%. If power voltage is not in this range, the unit may not operate normally.

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