Refrigeration leaks require a considerable amount of patience to discover. The problems is that leaks can be found anywhere along the system, from connections to hoses, valves and any other component. The unfortunate reality is that refrigerant leaks are usually discovered only after there has been a loss of cooling due to discomfort, spoilage, or production difficulty. Repairing refrigerant leaks is not the problem but finding them is. Which is so complicated due to them usually being concealed from view. This is a problem that we’ve run into more than a few times dealing with heat pumps.
Unfortunately, a single leak detection method that locates every leak in every possible situation simply does not exist. So, how do we determine which method is most appropriate for different air conditioning and refrigeration systems? To answer that question, let’s look at a few of the more common leak detection methods that are available.
- Visual inspection
- Bubble test
- Dye interception
- Electronic leak detectors
- Ultrasonic leak detectors
LEAK DETECTION METHODS
This is in the event of the sometimes rare case when you can visibly see the point where the refrigerant is leaking out, also occasionally refrigerant oil will also leak. All around the refrigerant piping, seals, cooling coils, valve caps, evaporator and the condenser coils, fittings and vibrating parts there may be stains discoloration or even the accumulation of dirt and oil. Each and every one of these things alone or tied together indicate the possible presence of a leak.
This is the oldest method of leak detection but one of the most used. Basically a soapy solution is applied at suspected leak points, typically with a squeeze bottle,brush or dauber. Theoretically then the escaping refrigerant should produce bubbles at the leak sites. The only problem is that very small leaks or windy conditions might make this method ineffective.
In this method, there’s a dye that is put into the system which would then become visible over time at the leak location.
There are two basic types of electronic detectors used to test for escaping refrigerant: corona-suppression and heated diode.
Corona-suppression technology measures variations in the conductivity of gases passing between two electrodes. The instrument creates a high-voltage dc spark that jumps from one point to another in the sensor, establishing a baseline current between the two points. A drop in current between the two points indicates the presence of an insulating gas. The greater the current drop, the higher the concentration of gas. One advantage of fluorescent leak detection is its ability to accurately pinpoint multiple leak sites in a system. Once the dye has circulated, inspection can begin with the system off or running.
Heated-diode technology consists of a ceramic element that heats refrigerant and breaks apart the molecules, leaving positively charged chlorine or fluorine ions that are attracted to a negatively charged center collection wire. The flow of chlorine or fluorine ions to the center collection wire creates a small current. As the refrigerant concentration between the electrodes increases, the current increases to a level that sets off an audiovisual alarm. Generally speaking, heated-diode sniffers are more accurate and less prone to false triggering than corona-suppression detectors.
Using highly sensitive microphones, these ac- or battery-powered devices listen for a high-pitched, inaudible sound caused by the turbulence that results when refrigerant escapes from a leak site. Once detected, an audiovisual alarm is sounded. Better ultrasonic detectors convert and amplify the inaudible sound of a leak into a more natural sound the human ear can easily identify.
Since there’s an unusually high cost of refrigerants, equipment repair, and the time and effort needed to locate leaks, proper preventive maintenance of air conditioning and refrigeration systems is not only essential but turns out to be VERY helpful. It is always advisable to select a leak detection method that pinpoints leaks quickly and accurately so refrigerant losses are kept to a minimum. By finding and repairing minor leaks early, headaches can often be avoided later. If you ever find yourself in need of HVAC services, you’ve found the right place! Give us a call.
A-1 American providing Air Conditioning, Heating and plumbing services like furnace repair services for homes and businesses in the Hampton Roads Virginia cities of Virginia Beach, Chesapeake, Norfolk, Portsmouth, Suffolk, Newport News and Hampton and north into Williamsburg. A-1 American provides emergency service and repair, 24 hours a day, 7 days a week, including weekends and holidays. A-1 American charges by the job, not by the hour. A-1 American prides itself on immediate response, punctuality, courtesy and customer satisfaction. Call today 757-425-2400