Mitsubishi Heavy Industries FDCW100VNX-A, Technical Manual

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Service
- 189 -
‘19 • HM-T-340
3) Heating high pressure protection
＜
FDCW60VNX
＞
a) Protective control
If the liquid line temperature of water heat exchanger (BT15=Thi-L) or the condensing saturated temperature (CST),
whichever the higher.
Exceeds the setting value, the compressor speed (frequency) is controlled at every 10 seconds to suppress the rise of
high pressure.
Reset
65
63
Reduce compressor speed by 4 rps
Reduce compressor speed by 8 rps
Tho-R(
℃
)
＜ FDCW71, 100, 140VNX ＞
a) Protective control
i) If the liquid line temperature of water heat exchanger (BT15=Thi-L) or the condensing saturated temperature
(CST), whichever the higher, exceeds the setting value, the compressor speed (frequency) is controlled to
suppress the rise of high pressure.
ii) Control value A is updated to an optimum value automatically according to the operating conditions.
60-63°C
Reset
Reduce compressor speed at every 10 seconds
Liquid line temperature of water heat exchanger or
condensing satureted temperature (°C)
b) Anomalous stop control
If the liquid line temperature of water heat exchanger (BT15=Thi-L) or the condensing saturated temperature (CST),
whichever the higher, exceeds the setting value for 2 seconds, compressor stops.
The compressor automatically restarts when the temperature gets 47°C or lower.
47
65
Compressor stop
Compressor operation
Liquid line temperature of water heat exchanger or
condensing satureted temperature (°C)
4) Anomaly detection control by the high pressure switch (63H1)
i) If the high pressure rises and activates the high pressure switch (opens at 4.15MPa/close at 3.15MPa), the
compressor stops.
ii) Under any of following conditions, HP alarm is displayed and E40 is recorded in the Error Log, and it enters the
anomalous stop mode.
①
When high pressure exceeds the setting value and the compressor is stopped by 63H1 5 times. within 60 minutes.
②
When 63H1 has been in the open state for 60 minutes continuously including the time of compressor stopping.
5) Low pressure control
a) Protective control
If the value detected by the low pressure sensor (LTP) exceeds the setting value, the compressor speed (frequency) is
controlled to restrain the drop of pressure.
0.150 0.189
Reduce compressor speed at every 30 seconds
Reset
Low pressure (MPa)
Retention
Operation control function by the outdoor unit control