Si20-701_B Troubleshooting by Remote Controller
352
3.85
U0
Refrigerant Shortage
Remote Controller Display
U0
Applicable Models
RZQ-K/H, RZQ(S)-B
Method of Error Detection
(In normal operation)
Refrigerant shortage is detected according to the
electronic expansion valve opening degree and
measured temperatures and pressures.
Error Decision Conditions
(In cooling operation)
When the electronic expansion valve opens fully and low
pressure is below 0.1 MPa (For RZQ-C, RZQG:
0.25MPa) continuously for 30 minutes.
(In heating operation)
When the electronic expansion valve opens fully and the
suction superheat is large (more than 20°C) continuously
for 30 minutes (For RZQ-C, RZQG: 60 minutes).
∗ Refrigerant shortage alarm is indicated but operation
continues.
Supposed Causes
îš„ The stop valve is not opened
îš„ Insufficient refrigerant amount
îš„ Clogged refrigerant piping system