Mitsubishi Electric PURY-EP200 Service Handbook page 282

[ IX Troubleshooting ]
1) BC controller: Phenomena when LEV is connected wrongly (reverse connection of LEV1 and LEV3) to the board.
Cooling-only
Non-cooling
SH12 small, SC11 small
SH16 small, branch pipe
SC small
BC controller sound
2) Check method of fully open state or fully closed state of LEV
Check LEV opening (pulse) on the self-diagnosis LED (Outdoor 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)
G, GA, HA
type
GB, HB
type)
HWE0713A
Cooling-main
Non-cooling and non-heating
SH12 small, SC11 small
SH16 large, but branch pipe
SC small
BC controller sound
PHM large
Malfunction
Part
mode
Inclined to
Heating only
close
LEV1
Inclined to
open
Cooling-only
Inclined to
close
Heating only
LEV3
Cooling-only
Inclined to
open
Heating only
Cooling-only
Inclined to
close
LEV3
Cooling-only
Inclined to
open
Phenomena
Heating only
Indoor heating SC small
PHM large
Operation
Content
mode
Difference between high
pressure (P1) and interme-
diate pressure (P3) is large.
Heating-
main
Difference between high
Cooling-
pressure (P1) and interme-
main
diate pressure (P3) is
small.
Cooling- SH12 is large.
main
Difference between high
pressure (P1) and interme-
Heating-
diate pressure (P3) is
main
small.
Cooling- SC16 and SH12 are small.
main
Difference between high
Heating- pressure (P1) and interme-
main diate pressure (P3) is large.
Cooling- SH22 is large.
main
Cooling- SH22 is small.
main
- 273 -
Heating main
Non-cooling
Indoor heating SC small
PHM large
Standards of judgment on
unit stable operation
0.3 to 0.4MPa
[44 to 58psi]
SH12 < 20°C [36°F]
0.3 to 0.4MPa
[44 to 58psi]
SC16 > 3°C [5.4°F]
SH12 > 3°C [5.4°F]
0.3 to 0.4MPa
[44 to 58psi]
SH22 < 20°C [36°F]
SH22 > 3°C [5.4°F]
GB