CHUNLAN -B, Service Manual

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Troubleshooting
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Chapter XII Troubleshooting
I. Failure codes
Microprocessor-based controller of this unit features troubleshooting and protection display
functions.
Display code
Failure category
FRD23-B,
FRD50-B
FRD50-B
FR(D)71-B
FR(D)100-B
FR(D)95, FR95-C
FR(D)125/S, FR125-C/S
FR(D)180/S
FR(D)260/S
High pressure protection --- E0 --- E0
Antifreeze protection E1 E1 E1 E1
ID ambient temp probe short
circuit
E2 E2 E2 E2
ID pipe temp probe short circuit E3 E3 E3 E3
OD pipe temp probe short circuit E4 E4 E4 E4
Communication failure E5 E5 E5 E5
Phase sequence protection --- --- --- E6
Overcurrent protection --- --- --- E7
Load relief protection E8 E8 E8 E8
Low pressure protection --- --- --- E9
In case of repeated protections of air conditioner, cut off power supply and have failure corrected
by specialty maintenance personnel, before restarting the machine.
II. Common troubleshooting
In case of AC failure, immediately cut off power supply. Check the following before
requesting maintenance:
Failure Causes Correction measures
Power off Use when power is resumed
Power not meeting requirement Check power supply before use
Machine not operating
Molten fuse or open CB
Replace fuse or close circuit
breaker
Clogged air strainer Clean air strainer
ID or OD unit air intake
clogged
Remove obstacles
Improper temp control setting Reset temperature control
Machine operating at
poor cooling/heating
efficiency, or not
cooling or heating
Open door/window Close doors/windows