technical & service manual dc inverter multi-system air conditioner
technical & service manual dc inverter multi-system air conditioner
technical & service manual dc inverter multi-system air conditioner
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(8) Branch tubing temperature sensor<br />
Check that the sensor is securely contained in the thermostat holder.<br />
(9) Breaker<br />
Check whether or not the breaker has been tripped.<br />
Check that the breakers and fuses used are of the specified capacity.<br />
Check that the breaker and its line are exclusive for A/C use.<br />
(10) Refrigerant gas pressure<br />
Start a COOL test run, and messure the temperatures of the A/C intake <strong>air</strong> and discharge <strong>air</strong>. Compare the values<br />
with the performance charts.<br />
If the values are higher than the performance charts:<br />
Check for refrigerant shortage or blockage of the refrigerant circuit.<br />
< Assessment of refrigerant shortage ><br />
1. The pressure in the low-pressure section is 5 MPa or more below the value in the performance charts.<br />
2. There is little condensation on the indoor heat exchanger, which overall appears dry.<br />
< Distinguishing between refrigerant shortage and refrigerant circuit blockage ><br />
If the pressure in the low-pressure section does not change when the circuit is charged 2 to 3 times with<br />
refrigerant gas (0.44 lbs each time), or if the change is small, then the problem may not be refrigerant<br />
shortage.<br />
The problem may be a blockage of the refrigerant circuit.<br />
1. Check that there is no internal leakage inside the 4-way valve:<br />
At the low-pressure side tubing, check that there is no temperature difference between the intake and<br />
discharge of the 4-way valve.<br />
2. Check that the electric expansion valve is not blocked. Check as described on the preceding page.<br />
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