The loss of refrigerant from a system due to a leak is a very common problem. It is normally an easy problem to diagnose; however, locating the source of the leak and repairing it may be difficult and frustrating at times.
It is always best to find and repair the source of the leak. But depending on the size of the system and the size and location of the refrigerant leak, it may not be an easy or inexpensive repair. Depending on the amount of refrigerant contained in the system, the Environmental Protection Agency (EPA) may require the source of the leak be located and repaired.
Currently, the EPA requires refrigeration systems containing 50 pounds of refrigerant or more and having an annual leak rate of 35 percent or more be repaired within 30 days from the date the leak was discovered. If replacement is required, a plan must be developed within 30 days to retrofit or retire the equipment, and the actions under that plan must be completed within one year. The EPA is changing the annual leak rate on Jan. 1, 2019, to 30 percent for industrial process refrigeration and 20 percent for commercial refrigeration. For systems containing less than 50 pounds of refrigerant, the EPA recommends the leak be repaired, which, again, is best for the customer, technician, and environment.
On some systems, especially on fractional horsepower systems, locating small leaks may be quite difficult — not impossible, but quite time-consuming and perhaps at a great expense to the customer. Many years ago, it was quite common for technicians to simply top off systems with refrigerant and not even look for the leak. Of course, this was when refrigerant was inexpensive and the EPA had no guidelines. Today, the practice is still used, but it is not common because the cost of refrigerant does not make it as practical as in the past.
Technicians often use refrigerant sealants to repair many small system leaks. These sealants can be a viable solution but should be used wisely and not as the first attempt at repairing a leak. Technicians should first strive to find the source of the leak by using standard industry procedures. Using a sealant as a first attempt can be problematic because, depending on the size and location of the leak, the sealant may not be effective. If the refrigerant leaks out again in a relatively short amount of time, the initial repair will generally be a waste of time for both the customer and the technician. The use of a sealant can be a great option, but only after it is confirmed that the leak is very small and difficult to locate.
A good first step in locating a leak is a simple visual inspection. As refrigerant leaks from a system, so does a portion of the refrigeration oil. The oil will normally stain the area surrounding the location. An easy way to search for a leak is to visually inspect the lines and fittings of the system for signs of oil. There are several different methods a technician can use to find these leaks, and each has its own advantages and disadvantages. Some may work well to locate a leak on one system and not as well on another. Technicians should have available, and be able to use, more than one leak detection method. If one method is not working well, they can switch to an alternate one. Also, it is often beneficial for technicians to employ two methods while searching for a leak: one to locate the general area of the suspected leak and the other to pinpoint its specific location.
It is always best to find and repair a system leak rather than simply topping off a system or using a refrigerant sealant as a first attempt. It is definitely a more time-consuming repair but most likely better for the customer in the long term.
Publication date: 9/3/2018