Contractors have an opportunity to check the cooling system for refrigerant leaks. Some of these options have been in development for years. The bubble method paved the way for dye kits and electronic hand-held HVAC refrigerant leak detectors.
Some refrigerant leak detection methods are now obsolete compared to the new test equipment, but the old techniques are still reliable and useful.
Given the large number of devices available for refrigerant leak detection, deciding which method to use in a given situation can be confusing.
Popular choice of refrigerant leak detector
The most common tool contractors use to identify refrigerant leaks is an electronic leak detector.
One of the earliest electronic leak detectors introduced in the industry is the negative corona discharge model. The device creates a high-voltage corona on a sensor chip. When the corona detects the refrigerant, the device sets off an alarm.
Early models of negative corona detectors had some problems introducing them. Large amounts of refrigerant can contaminate the detector and cause it to malfunction.
Another type of electron detector is a heated diode model. The technique heats the refrigerant to break down the molecules and produce positively charged chlorine or fluorine ions. A heated diode detector detects these ions and sends an alarm.
Over the years, both negative corona detectors and thermal diode detectors have been improved to be less sensitive to large refrigerant leaks.
False alarms are another drawback of some electronic leak detectors. However, as tools have become more complex, many manufacturers have been able to solve this problem. Previous models were able to detect other chemicals that might interfere with the test. These can lead to incorrect results and indicate a leak where there is no leak.
To avoid this problem, another type of electron leakage detector, the ultrasonic type, has been developed. The ultrasonic detector does not detect any refrigerant. The device is used to detect the level of refrigerant leaking from the system. The advantage of ultrasonic leak detectors is that they are insensitive to gases. This is useful for pressure measurements.
As with heating diodes and negative corona models, technological advances eliminate many of the problems associated with ultrasonic detectors, but can cause problems. One of the biggest problems with ultrasonic leak detectors is the possibility of background interference. Some models, particularly previous versions of the ultrasonic refrigerant leak detector, can pick up other inaudible sounds unrelated to the cooling system and set off alarms on the detector.
Fluorescent refrigerant leak detector
One of the oldest ways to detect refrigerant leaks is the bubble method. This option has expired, but is still valid and available. One of the great advantages of the bubble method is that contractors can visually see leaks.
To perform this method, apply the soap solution where a leak is suspected. If there is a leak, the refrigerant leaks and the solution starts to bubble.
Refrigerant bubble detection methods can be used with various advanced technologies.
The ultrasonic detector can be used with bubble solutions. The motivation behind this is to detect the inaudible cracking caused by the explosion of small bubbles in the solution caused by the refrigerant.
The latest way to clearly identify refrigerant leaks is to use fluorescent dye kits. Dye is injected into the cooling system to circulate the refrigerant. The next step is to direct ultraviolet light to different parts of the system where leaks may occur. If there is a leak, it glows when the refrigerant dye is detected under ultraviolet light.
If uv is present, no errors will be shown. If lit, no refrigerant leaks.
Dye kits can also be used in automotive refrigerant systems. Oil and steam from car engines can distort the measurements of the electronic leak detector.
However, uv and dye kits have disadvantages.
First, ultraviolet light works only in the parts of the cooling system that are accessible. If part of the system is hidden, the lights cannot be used.
Second, dye kits are not immediately effective in some applications. If the leakage is small, the uv may take some time to expose the infiltrating refrigerant. The limitation of the dye is that you may have to wait a day or more to identify the dye. This means that you must visit the site many times.
Long waiting times are usually due to the size of the leak. The bigger the leak, the faster the results. However, if the leakage is small, it may take longer.
Halide torch refrigerant leak detector
Another way to find leaks is to use a halogen burner. An older method USES the open flame of a halide burner to detect refrigerant leaks. When exposed to chlorine-containing refrigerants, the cutting torch flame turns green.
The intensity of the flame varies depending on the size of the leak. One of the most obvious disadvantages of this method is that halide burners are only affected by CFC or HCFC.
Halide burners still work, but many contractors don't like the idea of using open fires near refrigerants.
For those who choose halide burners, contractors should keep a few things in mind.
Environment and application play an important role in the effectiveness of equipment. In the wind, the flame can hardly absorb the gas. Sunlight can also be a problem. If there is little leakage, the flame will take on a subtle green color. If the outside light is too bright, the color of the flame may not change.
Therefore, it is not recommended to use this method outdoors, especially on roofing equipment.