Daewoo Q600 series, Service Manual

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1) Check the heat discharge at the COMP outlet while COMP is on. It depends on circumstances, but
the temperature should be higher than the surrounding. If you have the COMP on after making it off for 10 min.
or so, then you can easily detect the heat.
If there is no heat discharge detected, then it is not only due to bad GAS but one of the following:
a) GAS leakage
b) bad CYCLE blockage
c) bad COMP (bad discharge).
2) For a more precise diagnosis, check the temperature at the inlet/outlet of the condenser.
- Condenser inlet temperature should be -25℃↓, while condenser outlet temperature should be -20℃↓ or so.
(It may depend on circumstances.)
If the temperature at the inlet drops while that at the outlet does not, it may be due to lack of the refrigerant
by the GAS leakage.
One thing to remember is that you should have maintain both the Freezer and fridge
Compartment in the “Strong” state long enough before checking the temperature drops.
3) If it is thought to be bad as a result of the above checking, follow the process in that order for repair.
a) Have COMP stopped after having it run for 2~3min.
b) Cut the capillary tube at the dryer outlet.
If the refrigerant GAS is not ejected now, it is due to a CYCLE blockage or a GAS leakage.
If the refrigerant GAS is ejected, it is due to a lack of GAS or bad COMP (bad discharge).
c) Bad blockage may be judged through nitrogen blowing.
(Blowing pressure should be 6 kgf/cm2 or higher.)
Blowing direction should be toward the low pressure side of the COMP and you should check the discharge
to the capillary tube and HOT-PIPE outlet.
d) To check the bad COMP (bad discharge) you should check the discharge pressure while the COMP is running.
It should be 20 kgf/cm 2 (it depending on circumstances) or more.
If you have no pressure gauge, the pressure should be one you cannot block by your hand.
e) To see if it is due to a GAS leakage: If the refrigerant gas is not ejected when you cut the capillary tube
at the dryer outlet, check the possibility of a blockage. If it is not a blockage, then it is due to a leakage. To find
the leakage point, use a leakage detector, basically before the destruction of the CYCLE (in the refrigerant-sealed state),
or try to visually find out the oil leakage mark left on each pipe or welding point.
After a CYCLE destruction, use pressure gauge (0.001kgf/cm 2 or so) and soap water testing, after high
pressure nitrogen gas is injected into the Cycle.
7-10. Refrigerator Cycle Repair
7-10-1. Diagnosis Method (No Freezing/Refrigeration)
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