Samsung AM032MNQDCH/AA Service Manual page 298

Troubleshooting
4-4-55 : Comp. Down due to Low Pressure Protection Control
Outdoor unit display
Indoor unit display ×(Operation)
∙ Inspection when the value of low pressure sensor is 0.8kg//cm², or less for air conditioning and 0.6kg//cm² for
Judgment Method
heating
∙ Refrigerant shortage
∙ Electronic expansion valve blocked
∙ Service valve blocked
∙ Low pressure sensor defective
Cause of problem
∙ Leakage of compressor discharge check valve of not-go-end outdoor unit
∙ Error may be found when used in temperature range outside the conditions of use
(Operating outside temperature at -20°C or less for heating and operating outside temperature
at -5°C or less for Cooling)
1. Cause of problem
Are all service valves open?
estimated value and the Manifold
Gauge value in range?
Are the Indoor Unit and Outdoor
Unit EEV normally operating?
Are there any blockage inside
the pipe? (filter etc.)
Is there any leakage in
the Liquid Pipe Valve or the discharge check
valve of the not-go-end Outdoor Unit when
only some Outdoor Units
Check the refrigerant amount.
4-98
(Reservation)
Commissioning
Yes
Is the S-net
Yes
Yes
No
are operating?
No
(Blast) (Filter) ×(Defrost)
Connect S-net and Manifold Gauge.
No
No
Replace Low Pressure sensor
No
Yes
Yes
Replace relevant component
(essential requirement)
Open the Service Valve
Check the relevant EEV
Pipe inspection
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