11
9
Check code
[H07] / [d7]
(Current code / AI-NET)
Check code name
Oil level down
detection protection
Cause of operation
1. Valves of balance pipes closed.
2. Miscabling or misinstallation of TK1 to TK4 sensors
3. TK1 to TK4 sensor error
4. Gas leak or oil leak of all outdoor units
5. Refrigerant stagnation of compressor case
6. SV3A, 3B, 3D, 3C, 3E valve error
7. Clogging of oil return circuit from oil separator
8. Clogging of oil-equation circuit system
(Reference)
When refrigerant stagnates in compressor shell, the oil level shortage may be judged.
(
∗
2) Check clogging of oil return circuit
from oil separator. (Capillary tube, strainer)
Check clogging of SV3D valve.
Indoor/outdoor PMV error
(Cause of refrigerant stagnation),
discharge check valve error, etc.
No leakage or clogging
Choke
No choke
No choke
Replace faulty part.
Are all oil levels correct?
(
∗
1) Check leakage of valves
(SV3A, SV3C) and clogging (SV3B, SV3E).
Check clogging of solenoid valves (SV3A, SV3C)
of all outdoor units in the same line. (
∗
3)
Check refrigerant stagnation
in compressor.
Are characteristics of TK1 to TK4
of error-detected unit normal?
Are balance pipe valves
of all outdoor units in same line
fully opened?
Open balance pipe valves fully,
reset power supply,
and start operation.
Are TK1, TK2, TK3, and
TK4 sensors of the error-detected
unit correctly connected?
Is there no sensor detached
or misinstallation?
Correct miswiring and misinstallation.
TK1: CN514
TK2: CN515
TK3: CN516
TK4: CN523
Replace faulty part.
Replace faulty part.
Replace faulty part.
Sensor error
→
Replace
Specify gas leak position and repair it.
(Recharging, refill oil)
( )
∗
Characteristics-4
YES
7-segment display with
SW01/02/03=1/15/1
(Note)
(
∗
1), (
∗
2), (
∗
3) and (
∗
4). See page 100, 101.
Check gas leak of all outdoor units
in the same line and check soaked oil.
No error
Refrigerant stagnation
Correct refrigerant stagnation
in compressor,
reset power supply,
and start the operation.
Check oil level judgment of each unit.
Clear cause of stagnation.
Check clogging of oil equalization circuit.
(
∗
4)
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
FILE NO. SVM-1
40
77
