How To Resolve Ng Items - Samsung AM072BXV Series Service Manual

Test Operation
9-1 Auto Trial Operation (cont.)

9-1-3 How to resolve NG items

1) Indoor unit's thermistors
∙ What to inspect: Indoor unit's thermistors (the temperature of the indoor air and the temperatures at the entrance and exit
of the heat exchanger on the indoor unit)
∙ Error code: None ("NG" is only indicated in the result report)
∙ How to determine error: Check the temperature difference between the thermistors on the indoor units before
the compressors are started.
∙ Perform inspection according to the steps shown below.
Operate all the indoor units in
fan mode for 10 min.
Is there
an indoor unit with a thermistor
No
that shows a deviation greater than 10℃
compared to other
indoor units?
Is the device
used to read the indoor
air temperature for the indoor unit set to
the wired remote control?
Are the thermistor
connectors on the indoor unit properly
connected to the PBA?
Are the resistance
values* for the thermistors on
the indoor unit normal?
Are the thermistors
on the indoor unit attached to
the correct positions?
Replace the Hub PBA.
Perform Auto Trial Operation again.
■ Precautions
- If issues occur on multiple components at the same time, the inspection accuracy may degrade.
- If the device used to read the indoor temperature is set to the wired remote control, change the device to the indoor
unit's thermistors and then perform Auto Trial Operation.
Presence of an "NG" item may occur due to a temp difference according to the positions of the indoor unit and the wired remote control.
- Thermistors on indoor units where outdoor air is applied are excluded from inspection.
- To replace a component or inspect the PBA, be sure to cut off the power supply first. If inspection must be performed with the power
supply on, exercise extra care to prevent electric shock.
Samsung Electronics
Yes
Yes
No
No
Yes
No
Yes
No
Yes
Change the device
used to the indoor air temp
(Wired remote control
→ Indoor unit)
Take corrective measures.
Replace the thermistors.
Take corrective measures.
* How to measure resistance Disconnect
the thermistor connectors from the PBA
and then measure the resistance
between the terminals of the connectors.
Temperature (℃ ) Resistance (KΩ)
70
60
50
40
30
20 12.1
10 18.0
0 27.3
-10 43.0
2.2
3.0
4.2
5.8
8.3
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