8-2. Introduction to major repair work
Major repair method for freezing cycle
- 36 -
- Cut the end of the drier part (high pressure side) and
compressor charging part to remove the refrigerant.
- Use the compressor, drier, oil and refrigerant for R134a.
- For the parts with nitrogen sealing and vacuum wrapping, check
the "pik" sound before assembling. Use only the ones with
proper wrapping and immediately assemble and weld the parts.
- When welding the parts always substitute the nitrogen. (nitrogen
pressure: 0.1-0.2kg/cm
2
)
- Major repair work should be done in a clean work space with no
humidity.
- Connect the hose and vacuum pump of the manifold gauge to
the high pressure (drier part) and low pressure side (compressor
refrigerant charging part), and make it vacuum for more than 60
minutes.
- Vacuuming speed: 113/l/min
- Measure the bombe exclusively provided by LG for R134a within
the regulated value ±5g using an electric weight and insert it to
the refrigerant charging part of the compressor. (insert refrigerant
while operating the refrigerator)
- Weld carefully after pinching the charging part.
- Check for leakage in the re-welded parts
• Minor leakage: Use the electric leakage detector
• Major leakage: Use the naked eye or finger to check the oil
from the compressor
g
Caution: Do not use soap water for the leakage parts
- Cooling performance check
1. Check whether the heat emitter is warm by hand.
2. Check if the moisture is formed evenly around the evaporator
surface within the refrigerator.
- The flux of the silver welding part should be removed with soft
brush or wet cloth etc. (Flux can accelerate rusting and cause
leakage).
- The tools for R134a should be wiped off well so that dust and
moisture cannot be penetrated and kept in a clean tool box or
specified location.
- The installation after moving, should be done in accordance with
the installation method of the major repair for the refrigerator.
(Maintain a 5cm or more distance from the wall for the model
with the cooling fan in the mechanical room.)
Pliers, nipper
Pipe cutter, gas welder, nitrogen
gas
Welding rod (silver: IS430B,
copper: BCup-2)
Flux (Hydrux Korea)
Vacuum pump (for R134a),
manifold gauge
Bombe for R134a (mass
cylinder), refrigerant (R134a),
manifold gauge, electric weight,
punch off pliers, gas welder
Electric leakage detector, driver
(+)
Brass brush, cloth, tool box.
Work sequence
Major repair details
Work tools
Diagnose
problem
Exchange
and weld
parts
Vacuum
Check the
refrigerant
leakage and
cooling
performance
Charge
refrigerant and weld
the sealing
Arrange the
mechanical room
and tools
Move and
install
Remove
residual
refrigerant
