Checking For Gas Leak; Too Open Expansion Valve - Kubota KX080-3 Workshop Manual

WSM KX080-3 Service

8) Too open expansion valve

Phenomenon
Too high pressure at both low-pres-
sure and high-pressure sides
Frosty low-pressure pipe

(3) Checking for gas leak

1. If a refrigerant leak is suspected, check for it with a gas leak detector in the following procedure.
1) Preparatory checking: Connect a gauge manifold and check the refrigeration cycle pressure. Add
refrigerant as required to raise the in-circuit pressure. This helps to improve the gas leak detection
accuracy.
Read the gauge pressure with the compressor at rest. The outside air temperature must be above
15 , however.
°C
When the gauge pressure is above 0.4 MPa (4 kgf/cm
If the gauge pressure is below 0.4 MPa (4 kgf/cm
level and then go to check.
Reference
Check for gas leak in a well-ventilated place. If the sensor of an electric gas leak detector gets exposed
to gasoline, light oil or auto emission, it may wrongly react to these gases.
Gas leaking from a pipe connection may get blown away even by breeze. Apply the tip of the probe all
around the connection, not on a single spot.
Possible cause
Too much refrigerant in low-pressure
pipe
Expansion valve too open
(1) (2)
2
) or so, go straight to check.
2
), add refrigerant to achieve the 0.4 MPa (4 kgf/cm
(1)
VI-S-17
VI Air Conditioner
Correction
Replace the expansion valve with new
one.
(1) Low-pressure side
(2) High-pressure side
(1) Probe
2
)