Samsung AM080FX A Series Service Manual page 409

Test Operation
9-1 Auto Trial Operation (cont.)
9-1-3 How to resolve NG items (cont.)
8) 4-way valve
∙ What to inspect: Outdoor unit's 4-way valve operation
∙ Error code: None ("NG" is only indicated in the result report)
∙ How to determine error: Check the variations of pressure when the 4-way valve is operating.
∙ Perform inspection according to the steps shown below.
Does the result
of Auto Trial Operation show that the
pressure sensors are properly
functioning?
Yes
Is the 4-way
valve connector properly connected to
the PBA?
Yes
Is the pin-to-pin
voltage of the 4-way valve terminal on
the Hub PBA 220V?*
Yes
Is the coil
of the 4-way valve properly
functioning?
Yes
Perform Trial Operation (cooling/heating)
- See the instructions on Key operation modes.
Is the operation cycle normal?
Yes
Perform Auto Trial Operation again.
■ Precautions
- 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
No
Take corrective measures.
No
Take corrective measures.
No
Replace the Hub PBA.
∙ After completing trial operation in heating mode, measure the pin-to-pin
voltage on the 4-way valve terminal (there is no output in the terminal
after trial operation in cooling mode is turned off).
No
Replace the coil.
Is a symptom
No
caused by malfunction of
the 4-way valve
present?
Yes
No
Take corrective measures.
Replace the body of the
4-way valve*
* Perform inspection at least twice before
replacing the 4-way valve.
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