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Troubleshooting by Remote Controller Display / LED Display
SiBE28-804
238
Troubleshooting
Check for Excessive Refrigerant Charging
As criteria for judging whether refrigerant is excessively charged or not, refer to the following
operating conditions.
<Diagnosis of excessive refrigerant charging>
In cooling operation
(1) Because high pressure rises due to excessive charging, overload control is carried out and
capacity tends to run short.
(2) Considering pressure load, compressor discharge pipe temperature is low.
(3) Subcooled degree of condensate liquid becomes large. Therefore, temperature of blown air
passing through subcooled part decreases in heating operation.
Check No.14
Cooling
High pressure
Low pressure
Compressor
frequency
Electronic
expansion valve
Suction
superheat degree
Discharge
superheat degree
Adequate level
Compressor frequency
increases in order to
maintain low pressure.
Compressor frequency
decreases in order to
maintain high pressure.
Maximum frequency
Suction superheat degree is approx. 0 deg.
(Degree of excessive refrigerant charging)
As compressor
frequency decreases,
low pressure rises.
As compressor
frequency decreases,
low pressure rises.
Compressor frequency
decreases due to high
pressure protection control
Minimum frequency
Minimum frequency
Electronic expansion valve
opening degree decreases
due to wet protection control
Electronic expansion valve
opening degree decreases
due to wet protection control
Minimum opening degree
Excessive charge
High pressure
Low pressure
Compressor
frequency
Electronic
expansion valve
Suction
superheat degree
Discharge
superheat degree
Adequate level
Suction superheat degree is approx. 0 deg.
(Degree of excessive refrigerant charging)
Minimum opening degree
Excessive charge
Heating
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 ...