Si33-105
Outline of Control (Outdoor Unit) < Symbols using in this manual >
Function R407C PLUS Series Heat Recovery System
79
3.5.4 Inverter Protection Control
Controls the compressor upper-limit frequency to prevent tripping by inverter overcurrent and fin
temperature increase.
"
1: Upper limit frequency according to “step down control”.
3.5.5
High Pressure Protection Control
The following control is provided for the compressor operating frequency and others to prevent
protection devices from malfunctioning due to abnormal increase of high pressure (HP) and to
protect the compressors.
[Cooling and simultaneous cooling / heating operation mode]
[Oil return mode (common for cooling / heating)]
Outdoor unit fan and hot gas bypass solenoid valve (SVP) under oil return operation are
controlled not to actuate high pressure protection. Also outdoor fan is controlled to protect short
refrigerant circulation due to low high pressure during low ambient temperature. (Oil returning is
hard at short refrigerant circulation)
"
Movement
"
SVP of turns ON only when heating mode.
"
The step 1, 2 and 3 will be cancelled when the oil return operation is completed.
"
Refer p.96 for Fan step table.
Raising upper limit
frequency for -step
H
1
Normal operation
Lowering upper limit
frequency for -step
H
1
(V0832)
•
Inverter current > 30A
±
5%
•
INV fin temp. > 92˚C
OR
•
Compressor stop
•
Upper limit frequency= Max. frequency
OR
•
Inverter current
≤
30A
±
5%
•
INV fin temp. < 87˚C
•
3-min elapse
OR
(every 10 sec)
(every 3 min)
Step
SVP
Fan
"
ON
Step
OFF
Step
OFF
Step
Normal
operation
1 step down for upper limit
compressor operation frequency
H
Judge every 10 sec, and down
1 step until HP<2.45MPa
1 step increase for compressor
operation frequency
Forced
thermostat OFF
E3 normal
stop
HP
≥
2.45MPa
Retry
HP
≥
2.81MPa
HP
≥
2.45MPa
HP > 2.94MPa
HP < 2.16MPa
Continues 30 sec.
HP < 2.35MPa
Continues 5 min.
(V0823)
Up to 2 times
within 30 min
Upper limit frequency
= Max. frequency
&
•
Heating operation
•
Compressor stop
OR
&
OR
Step1
SVP : ON
Fan : Step
HP<1.72MPa
HP>2.16MPa
Step2
SVP : OFF
Fan : Step
HP<1.49MPa
HP>1.79MPa
Step3
SVP : OFF
Fan : Step
(V0825)
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 ...