Replacing Refrigrant in Cold Machine
The only reason to have to replace refrigrant in a cold machine is if you have a leak. Depending on the age of the unit, you could have either R12 or R134a refrigrant in the system. If you have R 12, you may find it almost impossible to get replacement without it being very costly. If you do have a leak, you need to address this first. It will require a technician to come out and find the leak and fix it. That means that you will probably have to use a leak detector or soap bubbles to check all the lines and fittings. Could also be in the evaporator. Ice picks have been known to cause damage. After the leak is detected, it is necessary to take the refrigerant out of the system and repair the leak. You need to have a special recovery pump to do this. They can save the refrigerant in a can and reuse it, if it isn't contaminated. Some technicians have special recovery units that include a filter system to reuse recovered refrigerant. The system will then need to be checked. They use nitrogen gas to do this. Again special regulator, ect. Don't use compressed air as you will just contaminte the entire system. After the leak is fixed, then you need to vacume the sysyem to get all the moisture out before adding the refrigerant. You will probably want to replace the filterdryer in the system and maybe even the compressor oil. Bottom line, is that you need to have a service technician do the work. In 1994 the EPA became involved in the Ref. industry due to the refrigerants causing a hole in the ozone layer. It is now highly regulated and you can't really do it yourself.Good luck.Bob