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[ IX Troubleshooting ]
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HWE09080 GB
1) BC controller: Phenomena when LEV is connected wrongly (reverse connection of LEV1 and LEV3) to the board.
2) Check method of fully open state or fully closed state of LEV
Check LEV opening (pulse) on the self-diagnosis LED (Heat source control board SW1).
Full open: 2000 pulses
Fully closed: 110 pulses (In the case of heating-only mode, however, the pulse may become 110 or more.)
When LEV is fully open, measure the temperature at the upstream and downstream pipes of LEV, and make sure that there
is no temperature difference.
When LEV is fully closed, check that there is no refrigerant flowing sound.
3) Refer to the chart below to judge LEV opening controlled by the values of the differential pressure and of the superheat.
(BC controller LEV basic operation characteristic)
Phenomena
Cooling-only Cooling-main Heating only Heating main
Non-cooling
SH12 small, SC11 small
SH16 small, branch pipe
SC small
BC controller sound
Non-cooling and non-heating
SH12 small, SC11 small
SH16 large, but branch pipe
SC small
BC controller sound
PHM large
Indoor heating SC small
PHM large
Non-cooling
Indoor heating SC small
PHM large
Part
Malfunction
mode
Operation
mode
Content
Standards of judgment on
unit stable operation
G, GA
type
LEV1
Inclined to
close
Heating only
Heating-
main
Cooling-
main
Difference between high
pressure (P1) and interme-
diate pressure (P3) is large.
0.3 to 0.4MPa
[44 to 58psi]
Inclined to
open
Difference between high
pressure (P1) and interme-
diate pressure (P3) is
small.
LEV3
Inclined to
close
Cooling-only
Cooling-
main
SH12 is large. SH12 < 20°C [36°F]
Heating only
Heating-
main
Difference between high
pressure (P1) and interme-
diate pressure (P3) is
small.
0.3 to 0.4MPa
[44 to 58psi]
Inclined to
open
Cooling-only
Cooling-
main
SC16 and SH12 are small.
SC16 > 3°C [5.4°F]
SH12 > 3°C [5.4°F]
Heating only
Heating-
main
Difference between high
pressure (P1) and interme-
diate pressure (P3) is large.
0.3 to 0.4MPa
[44 to 58psi]
GB, HB type LEV3
Inclined to
close
Cooling-only
Cooling-
main
SH22 is large. SH22 < 20°C [36°F]
Inclined to
open
Cooling-only
Cooling-
main
SH22 is small. SH22 > 3°C [5.4°F]