[
VII
Control ]
- 146 -
HWE09130
GB
(5) Bypass solenoid valve (SV5b) (ON = Open)
-6- Compressor Frequency Control
Depending on the capacity required, the frequency of the compressor is controlled to keep constant evaporation temperature
(0°C [32°F] = 0.71 MPa [103 psi]) during cooling operation, and condensing temperature (49°C [120°F] = 2.88 MPa [418 psi])
during heating operation.
The table below summarizes the operating frequency ranges of the inverter compressor during normal operation.
The OS in the multiple-outdoor-unit system operates at the actual compressor frequency value that is calculated by the OS
based on the preliminary compressor frequency value that the OC determines.
The maximum frequency during heating operation depends on the outside air temperature and the dipswitch settings.
(1) Pressure limit
The upper limit of high pressure (63HS1) is preset, and when it exceeds the upper limit, the frequency is decreased every 15
seconds.
The actuation pressure is when the high-pressure reading on 63HS1 is 3.58MPa[519psi].
(2) Discharge temperature limit
Discharge temperature (TH4) of the compressor in operation is monitored, and when it exceeds the upper limit, the frequency
is decreased every minute.
Operating temperature is 115°C [239°F].
(3) Periodic frequency control
Frequency control other than the ones performed at start-up, upon status change, and for protection is called periodic frequen-
cy control (convergent control) and is performed in the following manner.
Periodic control cycle
Periodic control is performed after the following time has passed
30 seconds after either compressor start-up or the completion of defrost operation
30 seconds after frequency control based on discharge temperature or pressure limit
The amount of frequency change
The amount of frequency change is controlled to approximate the target value based on the evaporation temperature (Te) and
condensing temperature (Tc).
Operation
SV5c
ON OFF
While the unit is stopped
Always ON
Cooling mode
When one or more of the following
valves is turned OFF: SV4a
through SV4c.
When the condition on the left is not
met
Defrost mode
Always OFF on the P72 and P96 models and
always ON on the P120 and P144 models.
Others
Always OFF
Model
Frequency/cooling (Hz)
Frequency/heating (Hz)
Max
Min
Max
Min
P72 model
43
14
52
19
P96 model
61
18
74
15
P120 model
75
18
86
15
P144 model
87
18
104
15
Summary of Contents for PURY-P120
Page 1: ...Models PURY P72 P96 P120 P144T Y JMU A PURY P168 P192 P216 P240 P264 P288T Y SJMU A ...
Page 11: ... 2 ...
Page 25: ... 16 ...
Page 36: ... II Restrictions 27 HWE09130 GB ...
Page 50: ... II Restrictions 41 41 HWE09130 GB ...
Page 67: ... 58 II Restrictions GB HWE09130 ...
Page 69: ... 60 ...
Page 95: ... 86 III Outdoor Unit Components GB HWE09130 ...
Page 97: ... 88 ...
Page 105: ... 96 IV Remote Controller GB HWE09130 ...
Page 107: ... 98 ...
Page 125: ... 116 ...
Page 145: ... 136 ...
Page 175: ... 166 VII Control GB HWE09130 ...
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Page 363: ... 354 IX Troubleshooting GB HWE09130 ...
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