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SiBE28-804
Frequency Regulating Functions
Functional Description
75
4.11 Pressure Difference Control
Outline
To ensure the compression ratio (pressure difference between high and low pressure) at low
outdoor temperature conditions in cooling mode and high outdoor temperature conditions in
heating mode, the outdoor fan and target compressor frequency may be varied.
Cooling
In cooling low ambient conditions, the outdoor fan speed and compressor frequency will be
adapted to secure the differential pressure between high and low pressure.
Fan control in
cooling
C Series : RZQ71~140C7, RZQS71~140C7V1B
Normal control
Upper limit (step 8)
Upper limit (step 8)
Upper limit (step 7)
Upper limit (step 6)
Upper limit (step 5)
Upper limit (step4)
Upper limit (step 3)
Upper limit (step 2)
Upper limit (step 1)
Upper limit (step 0)
= Outdoor fan OFF
Condition B
Condition B
Condition B
Condition B
Condition B
Condition B
Condition B
HP < 29 bar
∆
P > 11bar
Compression ratio > 2.4
Condition B
90 seconds have passed
HP > 23bar
∆
P > 10bar
Compression
ratio >2.2
&
&
&
Ta > 27°C
OR
OR
&
&
OR
OR
&
OR
T
Fin
< 66°C
90 seconds have passed
HP < 16 bar
∆
P < 8bar
Compression ratio < 1.8
90 seconds have passed
HP < 16 bar
∆
P < 8bar
Compression ratio
≤
1.8
Condition A
∆
P < 9.3bar
Compression ratio < 2.1
HP < 19 bar
Ta < 25°C
&
OR
HP > 17 bar
Tfin
≥
81 °C
∆
P > 9bar
Compression
ratio > 2.0
Condition A
Condition A
Condition A
Condition A
Condition A
Condition A
Condition A
Summary of Contents for FHQ100BUV1B x 2
Page 13: ...SiBE28 804 2 ...
Page 19: ...Model Name and Power Supply SiBE28 804 8 General Information ...
Page 29: ...Specifications SiBE28 804 18 Specifications ...
Page 33: ...Wired Remote Controller SiBE28 804 22 Remote Controller 1 2 Installation ...
Page 34: ...SiBE28 804 Wired Remote Controller Remote Controller 23 ...
Page 93: ...Outdoor Unit Fan Speed Control SiBE28 804 82 Functional Description ...
Page 131: ...Test Run and Operation Data SiBE28 804 120 Test Operation ...
Page 251: ...Troubleshooting by Remote Controller Display LED Display SiBE28 804 240 Troubleshooting ...
Page 277: ...PCB Layout SiBE28 804 266 Appendix ...
Page 297: ...RZQ100 140C7 RZQS125 140C7V1B SiBE28 804 286 Removal Procedure ...
Page 311: ...SiBE28 804 iv Index ...