When assembling the joint, always use new O-rings soaked in clean 525 grade cooling oil. It is much easier to assemble the parts lubricated with oil, and the oil will also ensure the tightness of the joint. When tightening the joints, use a second wrench to hold the stationary parts of the joint more firmly. This will ensure the strength of the assembly.
Replacing the sealing ring
Each time you remove a joint or fitting, you must install new gasket rings intended for replacement in the air conditioning system, unless these rings are already installed on new parts. Although all O-rings look the same, it is extremely important to use only those recommended for replacement in the air-conditioning system when changing, as otherwise there may be a refrigerant leak.
When replacing O-rings on air conditioning components, it is important to accurately determine the configuration of the fitting so that the replacement ring will fit the contour of the component. Some butt joints and components have so-called "grab" fittings, which have grooves to hold the O-rings, but there are also those that do not have a groove and use "non-grab" or "standard" O-rings, the installation and tightening process for both designs is the same, but the O-rings are different.
Before installation, also check that neither the rings nor the fittings are damaged or deformed. Deformed or damaged parts must be replaced.
Maintenance of cooling system lines and fittings
Flexible hose lines must not be twisted to a radius greater than four times the hose diameter.
Flexible hose lines should be inspected regularly as they may leak due to their fragility and replaced with new lines if a leak or line break is detected.
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Before you disconnect a fitting in the cooling system, you must first drain all the refrigerant. This must be done very carefully, regardless of the reading on the gauge. Open the system very slowly, keeping your face and hands away so as not to injure them if liquid refrigerant suddenly appears in the line. If you notice that the refrigerant is under pressure when loosening the fitting, first relieve the pressure as described when discharging, adding oil, evacuating and charging the air conditioning system.
If you find one of the refrigeration lines open, immediately replace the caps or tighten them to prevent moisture and dirt from getting in and causing wear on the compressor's internal parts or blocking the line, condenser and evaporator core tubes, expansion (expansion) tube or compressor inlet filters.
When installing connections on O-ring fittings, it is necessary to use the appropriate wrenches. To prevent the connecting lines or components from being bent, the fitting on the opposite side should always be supported with a wrench. When connecting flexible hose connectors, it is important that the stamping fitting and flare nut, as well as the coupling to which they are attached, are held simultaneously with three different wrenches, which will prevent the fitting from rotating and prevent damage to the main seat.
The sealing rings and seats must always be in excellent condition. A burr or piece of dirt can cause a coolant leak. When replacing the sealing ring, first dip it in clean 525 viscosity cooling oil.