Freon is one of Dupont’s trademark names and refers to a generation of refrigerants that are still in use, but that are also being replaced by newer and safer refrigerants supplied by many other manufacturers. The most common of these being phased out is R22 and coming on stream is R410A.
All types of refrigerants, new and old, are in a pressurized state and are contained within a closed loop. The amount of refrigerant required to flow throughout the outdoor condenser and the indoor evaporator is pre-determined by the manufacturer and design of the complete system. You see, Freon, or refrigerant, is not something that is consumed like gas or oil in your vehicle. So, if an air conditioning system is “low on Freon,” it is logical that a leak has allowed it to escape. A leak that is not found and repaired will continue to allow high pressure refrigerant to escape.
While refrigerant is often thought of as a toxic gas, it is actually more inert than many of the gases used around the home. The primary danger is that it will replace the present oxygen which will then cause people to have trouble breathing. However, this only happens in confined spaces with large amounts of escaped refrigerant. Nevertheless, you cannot replace the refrigerant yourself. It takes a certified HVAC repair person with the correct equipment to find the leak, fix it, evacuate any contaminants, and only then pump more refrigerant back in the system and test the level. Not so easy.
A large leak can sometimes be heard by a hissing sound or seen by spraying a soapy mixture and looking for bubbles at the source. Smaller leaks, however, will take more skill and detection tools to locate. Electronic or halide detection by a qualified service person can be time consuming and costly, but it is still worth doing on a system that is otherwise in good condition and less than 15 years old. A well-used central air conditioner will develop thin copper or aluminum lines or channels over time. This is when leaks are more likely to occur which makes it more difficult to provide a lasting repair. At this point, equipment replacement is worth looking into and could become the most practical long term solution.
Returning to the vehicle comparison, once your vehicle’s tires are thin, leaks will be more prominent. So, extremely small leaks in the evaporator or condenser coils are much the same as a radiator leak in your vehicle where it bleeds through in multiple tiny penetrations. Pressure testing with high pressure nitrogen will make a leak more detectable, but can also create a situation where an older, thinned out coil starts to bleed even more from the pressure test. Coil leaks are generally not repairable and require replacement as a complete component.
The refrigerant in a central air conditioner should last the life of the equipment, but in some cases contaminants can also enter into the system. In this case, a professional may suggest flushing and recharging the system completely. Not so easy.
Topping up Freon is not a practice that any certified technician should be asked to do when fines and penalties outweigh any perceived gains on short term savings. It becomes a slippery slope to poor service and callbacks when an Air Conditioning contractor provides warranty for refrigerant leak detection that is anything short of complete.
Without passing the buck to Equipment Manufacturers, they are all mandated to produce more efficient systems to reach minimum SEER levels. More now than ever before, air conditioners are being made with lighter and thinner materials. For instance, the new R410A refrigerant operates at 50% or more pressure which makes it much more likely for leakage issues. If you compare an older system that was not serviced when it should have been to newer, unserviced R410A equipment, this combination only gets worse.
Most manufacturers are offering equipment warranties that cover parts and compressors for up to 10 years and have little or no coverage for the copper lines and refrigerant supplied by the installing HVAC contractor. Based on contractor responses from recent surveys, equipment refrigerant leakage is proving to be the most common issue. It would be foolish for a manufacturer to offer a new product line with limited quality control testing, but with the rush to compete with the latest processes, it is becoming more common than ever to find poorly designed evaporator and condenser coils. It is worth mentioning that Goodman has gained huge market share in the US and Canada simply because they offer the cheapest (and flimsiest) product on the market today and in recent past.
As a consumer you should have all of your questions and concerns addressed before making an informed decision concerning equipment and leak repairs. Now you can see it’s not so easy.