Pump Down Control; Abnormal Stop By Failing In Starting The Compressor; Compressor Rotor Lock Error - Mitsubishi Heavy Industries FDTCVA SERIES Technical Manual

(m) Pump down control
If the pump down button SW1 (SW9) is kept on pressing for 2 seconds during an operation stop and anomalous stop (not
including when the thermostat is OFF), pump down operation starts. (It is disabled during indoor unit operation. It is enabled
during an anomalous stop of the indoor unit and during power OFF.)
Make sure the service valve on the liquid line is closed before starting pump down operation. (Leave the gas side fully
open.)
( i) Control contents
1) Compressor starts with cooling mode and the target speed at 55[62] rps.
2) The red and green indicators (LED) on the outdoor unit control PCB keeps fl ashing.
3) Except for low pressure control, each protective and anomalous sensing control is enabled.
4) The outdoor fan is controlled the same as normal.
5) The electronic expansion valve (cooling, heating) is fully opened.
6) The oil bypass valve (SV2) or solenoid valve (SV1: Model 302) is open for 2 minutes after the pump down operation
starts and after that, it closed.
Note (1) Valves in [ ] show in the case of the 302 model.
(ii) Control end conditions
Stop control is executed according to any of the following conditions.
1) A low pressure of 0.087 MPa or lower is detected continuously for 5 seconds.
Red LED: Lights continuously, Green LED: Keeps fl ashing, Remote controller: displays stopped.
Restarting is possible when low pressure exceeds 0.087 MPa.
The electronic expansion valves (cooling, heating) remain fully open.
2) Stop according to error detection control.
Red LED: Lights continuously, Green LED: Keeps fl ashing.
Restarting is not possible. ordinary operation is restored by resetting the power supply.
The electronic expansion valves (cooling, heating) remain fully open.
3) When the cumulative compressor operating time by pump down control is 5 minutes.
Red LED: Stays OFF, Green LED: Keeps fl ashing, Remote controller: Stop.
Re-pump down operation is possible.
The electronic expansion valves (cooling, heating) remain fully open.
Note (1) Close the gas side operating valve after the compressor stops.
Caution: If the pump down switch is pressed, communications with the indoor units is cancelled, so the message
"communications error – E5" is displayed on the indoor unit and the remote controller, but there is no error.
(n) Abnormal stop by failing in starting the compressor (Models 402 ~ 1002 only)
( i) If the unit cannot switch to compressor DC motor rotor position detection operation 5 seconds after compressor start
conditions are established, it enters a pause state, then after 3 minutes, the compressor is started again.
(ii) If switching to position detection operation cannot be done a second time, an anomalous stop (E59) occurs due to a
compressor start error.
(o) Compressor rotor lock error (Models 802, 1002 only)
Auto restart occurs 3 minutes later, but if this occurs 4 times in 15 minutes, an anomalous stop (E60) occurs.
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