What does a refrigerant do in a cooling system?
A refrigerant plays the role of a heat-transfer medium in any refrigerant or cooling system (portable air conditioner, indoor air, outdoor unit, room air conditioner, central air conditioning, window air conditioner, car, etc).
The refrigerant moves through the entire system, beginning as a liquid and absorbing heat and turning into a gas as it goes. It is then condensed to become liquid again, releasing the heat and depositing it outside.
What are some common refrigerants?
The most common refrigerants are halocarbons, which include: CFCs (compounds of chlorine, fluorine, and carbon; invented in the 1920’s and used until their phaseout in the 1990’s), HCFCs (compounds of hydrogen, chlorine, fluorine, and carbon; now phased out in the US), and HFCs (compounds of hydrogen, fluorine, and carbon; in the process of being phased out in the US).
The stability of common refrigerants
Among common refrigerants, R-12 and R-22 (both classified as CFCs) are considered highly chemically stable under normal conditions, but their chlorine content renders them susceptible to breakdown when exposed to high temperatures or UV radiation, and they have a higher potential to deplete the ozone layer. R-134a (an HFC) is also very stable, making it a preferred replacement due to its lower ozone depletion potential, though it still has high GWP (global warming potential).
What is the average lifespan of old refrigerants?
Refrigerant (commonly known as “Freon”) is meant to last the entire lifetime of an air conditioning system. If it does degrade, it is not necessarily in the way that we might imagine, like fuel or oil in a car that needs to be replaced regularly. Instead, it remains intact, unless it degrades due to exposure to heat, pressure, and other system components (e.g. oil, moisture, or other particles).
A refrigerant system is a closed or sealed system, meaning that it is built to not allow refrigerant to escape in any way. But time can take its toll on even the most well-built system. A refrigerant leak can occur at fittings, valves, or through pinhole leaks that form due to aging or corrosion. These leaks, plus mechanical failures, can affect the chemical balance of hybrid refrigerants, causing a drop in performance when their mix inside the system becomes uneven.
How do I know if there is refrigerant loss or degradation in my cooling system?
Low refrigerant levels can cause a range of problems with your air conditioning system, but there are ways to tell if this is happening. Here are some things to look for:
- Warm air flow
- Reduced cooling efficiency
- Ice buildup on the evaporator coil
- Audible hissing or bubbling noises
- Water leaks
- High humidity in your home
How long does a car AC system last?
With regular monitoring and proper maintenance, car air conditioning or cooling systems have a lifespan of eight to fifteen years before needing repairs (this is how long your car’s air conditioning compressor is likely to remain in good working condition). But general wear and tear can lead to leaks in hoses or seals, and to refrigerant loss.
There are also other factors that can impact how long it takes before your car’s air conditioning system needs repairs. The two main ones are: the climate you live in, and the frequency with which you use the air conditioning in your car. The hotter the area you live in, the more likely it is that your car’s air conditioning system will need regular repairs.
Common signs that your car’s air conditioning system is losing function include:
- The air conditioning is not as cold as it used to be
- There are noises coming from the engine
- Visible corrosion
- The compressor clutch does not engage, or makes a screeching or whining sound
As with any air conditioning unit, for energy efficiency and the health of the system as a whole, keep an eye out for these signs, and make sure regular maintenance is on your to do list. It can save you a lot of time and money, and preserve the health of your entire cooling system.
