As we all know, most of the refrigerant leaks around 90% are caused by details at the time of installation of the equipment; the other 10% is due to different external factors such as vibrations, blows, fractures in the tube, etc.
The symptoms of air conditioning equipment when presenting a refrigerant leak can be several; we describe them below:
1) Lack of cooling capacity.
2) It never reaches the desired temperature.
3) Lack of air flow and strange noises in the evaporator.
4) Dripping or spilling water.
5) Freezing in the low-pressure line after the expansion device.
6) Low refrigerant pressure after checking it with the pressure gauges.
7) Low current consumption in amps of the system.
The necessary tool to carry out these works or reviews would be the following:
1) Nitrogen or refrigerant gas. (To add positive pressure to the system)
2) Electronic leak detector or water with liquid soap.
3) A container filled with water to submerge the equipment in parts.
4) Nitrogen Regulator and Manometers.
5) Parakeet keys, screwdrivers, Allen keys, etc.
6) Oxi-Gas equipment or hand torch.
7) Welding of 5% silver alloy.
Step No1: Be in the machine that has a lack of refrigerant or is empty.
Step No2: Add Nitrogen to 350Psi or Refrigerant to the system as it enters.
Step No3: With the machine turned off, check the welds, nuts or joints that were made at the time of installation of the equipment with its electronic leak detector or with water with liquid soap.
( NOTE: If the test is with refrigerant and the leak is in the suction with the equipment turned off it is the most efficient way to locate the leak if it is in the discharge or on the high-pressure side it is easier to detect it with the machine on ).
In the event that the leakage is not detected with the aforementioned procedure, it is most likely that the system has a microleakage, in this case the system would have to be separated into 2 or more sections evaporator, condenser and interconnection pipe, after pressurize them with nitrogen at 500 Psi and then immerse the evaporator, condenser, interconnecting pipe in the container with water and look for bubbles in the solders or joints in the coils, after having detected the leak repair it, if it is somewhere where it does not can be repaired you have to replace the complete piece.
It is important to take into account that for the repair of the leak, if the system operates with refrigerant R-410A, nitrogen must be run through the component when it is being welded in order to avoid the generation of soot inside the pipe and then clog the expansion device, if the system operates with refrigerant R-22 here you can use the same procedure or only sweep the refrigeration system with nitrogen at the end of the welding.
I hope and this information will be useful and take into account what is necessary to review and repair the damaged equipment.