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Expansion Valve Regulating Functions
SiBE28-804
78
Functional Description
5. Expansion Valve Regulating Functions
5.1
Expansion Valve Control at Startup
Outline
Before going to the general expansion valve control, the expansion valve opening will be limited
in order to avoid the risk of liquid back and allow quick build up of pressure difference.
Details
During startup, the opening degree is determined by both the compressor frequency & the
suction superheat. During startup, it is not possible to use only the value of the suction
superheat because the operation is not stable yet. As a consequence also the SH value will not
be stable.
Graph
RZQ71~140C7, RZQS71~140C7V1B
Expansion valve
opening during
pressure
equalization
On RZQ71, RZQS71·100 units (using double swing compressor) the expansion valve will be
fully opened (to 480 pulses) for pressure equalisation before compressor start-up. Just before
compressor start up, the expansion valve opening will be set to 65 pulses, same as for the
RZQ100~140 class.
Ending condition
The starting control will be terminated when the low pressure value < 6 bar or when the
maximum starting time of 10 minutes has been reached in case the low pressure value stays >
6 bar.
112Hz
Pressure
equalizing
complete
Starting
control
complete
Pressure equalizing
control before
compressor start
Starting
control
Compressor
Electronic
expansion valve
Cooling or
Heating(<25˚ C)
65 pls
Heating(>25˚ C)
480 pls
Pressure
equalizing
start
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 ...