Mitsubishi SRK63ZEA-S1, Technical Manual

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(8) Heating low outdoor temperature protective control
◆
< I >
(a) Operating conditions: When the outdoor air temperature sensor (Th5) is 4°C or lower continues for 30 seconds while
outdoor speed is other than 0rps.
(b) Detail of operation: When the inverter command speed is less than 20rps, the speed is forcibly set at 20rps. However,
when the thermo becomes OFF, the speed is reduced to 0rps.
(c) Reset conditions:
When the outdoor air temperature sensor (Th5) becomes 6°C or higher.
◆
< II >
(a) Operating conditions:
When the outdoor air temperature sensor (Th5) is 4°C or lower continues for 30 seconds while
outdoor speed is other than 0rps.
(b) Detail of operation:
Outdoor fan is stepped up by 2 speed step. (Upper limit 7th speed)
(c) Reset conditions: When the outdoor air temperature sensor (Th5) becomes 6°C or higher.
◆
< III >
(a) Operating conditions: When the outdoor unit is operating with the speed of other than 0rps, and when the outdoor heat
exchanger temperature (Th4) is less than -18°C.
(b) Detail of operation: The inverter command speed upper limit and corresponding outdoor heat exchanger temperature
are set as follows.
(c) Reset conditions: When the either of the following conditions is satisfied
1
When the outdoor heat exchanger temperature (Th4) becomes -16°C or higher.
2
When the inverter command speed is 0rps.
(9) Compressor protection start
(a) When the indoor unit calculated speed is 30rps or over at operation start, the unit is operated with 30rps for 1 minute and 45
seconds. After that when the calculated speed is 38rps or over, the unit is operated with 38rps for 1minute and 15 seconds.
After that when the calculated speed is 46rps or over, the unit is operated with 46rps for 1minute. After that when the
calculated speed is 54rps or over,the unit is operated with 54rps for 1minute then moved to command speed.
(b) At thermo operation (OFF
→
ON) this control is not executed.
(c) The indoor unit fan corresponds to the command speed of each operation mode.
Note (1) When the calculated speed is less than 30 rps, the unit is started with low load starting described in article (11).
(10) Inching prevention
When the compressor goes into the thermo operation within 5 minutes since operation start or becomes various dehumidifying
operations, the operation is continued with the command speed of 12 rps forcibly.
(11) Low load starting
(a) When the unit is started with calculated speed of less than 20 rps, it is operated with 20 rps for 60 seconds, then the operation
is moved to the command speed.
(b) The indoor fan corresponds to the operation mode.
Cooling:
Speed corresponding to the command speed of air flow switching
Dehumidification: Speed decided in the operation region
Heating:
The lower one between the speed corresponding to the command speed and the hot keep speed
-16
ON: 70rps
O F F
ON: 40rps
ON: 20rps
-18 -20 -25
Outdoor heat exchanger temp.(
°
C)