Troubleshooting
Si33-105
172
Troubleshooting R407C PLUS Series Heat Recovery System
3.16 Outdoor Unit:
Actuation of Low Pressure Sensor
Remote
Controller
Display
E4
Supposed
Causes
!
Abnormal drop of low pressure (0 kg/cm² [0 MPa])
!
Defect of low pressure sensor
!
Defect of outdoor unit PC board
!
Stop valve closes
Troubleshooting
"
1: Voltage measurement point
"
2: Refer to pressure sensor, pressure / voltage characteristics table on P243.
(V2735)
Low pressure
at stop due to malfunction is
0.0 MPa.
Measure
the voltage (VL)
of X21A pin No. (2) - (3)
of outdoor PC board (A1P).
H
1
Is the relationship
between low voltage
and VL
normal?
Out of gas, refrigerant system
clogging, wiring and piping wrong
connection.
Replace the low pressure sensor.
Replace outdoor unit PC board A1P.
NO
NO
YES
YES
Is the stop valve
on outdoor unit opened?
Open the stop valve on outdoor unit.
YES
NO
Caution
Be sure to turn off power switch before connect or disconnect connector,
or parts damage may be occurred.
Summary of Contents for R407C PLUS
Page 1: ...System R407C PLUS Series Heat Recovery System Si33 105 Service Manual ...
Page 11: ...Introduction Si33 105 x ...
Page 41: ...Specifications Si33 105 30 Specifications R407C PLUS Series Heat Recovery System ...
Page 147: ...Test Operation Si33 105 136 Test Operation R407C PLUS Series Heat Recovery System ...
Page 263: ...Si33 105 iv Index ...