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Refrigerant is the backbone of your air conditioning unit. If it leaks, it reduces the performance of the system and eventually damages it. The leak often happens when your HVAC system has been working overtime, especially when cooling RVs or travel trailers. Since you can’t rely on your nose to sniff out the source of the leak, we have come up with some of the best AC leak detectors available in the buying guide below.

Inficon TEK-Mate Refrigerant Leak Detector

A lightweight, portable, and highly sensitive leak detector with a sensor that offers over 1,000 hours of use.

LotFancy Refrigerant Freon Leak Detector

An affordable leak detector that can detect all kinds of halogen refrigerants. The unit runs on heated diode technology.

Fieldpiece Heated Diode Refrigerant Leak Detector - SRL8

Sensitive to all HFCs, HSFCs, CFCs, and blends. Fifteen-hour rechargeable battery. A filter system helps protect the detector from damage.

Our reviews are driven by a combination of hands-on testing, expert input, “wisdom of the crowd” assessments from actual buyers, and our own expertise. We always aim to offer genuine, accurate guides to help you find the best picks.

When used sparingly, UV dyes can be quite efficient in detecting leaks in a system. You need a UV dye and UV light to detect the source of the leak. You simply have to apply the dye on the suspected leak points and shine a UV light on them to illuminate the leaks. Be sure to find a dye that’s compatible with your compressor’s oil to avoid damaging the compressor and shortening the life of the air conditioner.

This is a simple and efficient, but time-consuming, way of detecting a leak. You can either dip the suspected leak point in a bucket of soapy water or apply soap and water to the suspected trouble points. Either way, you will notice bubbles coming from the leak points. It’s a convenient way to test the leak if you are alone and don’t want to risk having a room filled with refrigerant.

Electronic leak detectors are simple, handheld devices that identify the exact location of a leak. You have to get close to the suspected leak point to get a reading from the gadget. There are Corona–Suppression detectors that use a high-voltage corona on the sensing tip to detect a leak and heated diode detectors that use heat molecules to detect leaks. Another type is ultrasonic detectors that use sound to detect a leak in the refrigerant. All these units will light up or sound an alarm if there’s a leak. 

Inficon was founded in 2000 after the merger of vacuum technology companies under a Swiss company, The Oerlikon Group. The company manufactures innovative products featuring the latest technologies, and some of its products include vacuum components, vacuum gauge controllers, HVAC service tools, and leak detectors. If you are looking for an R22 refrigerant leak detector, try out the Inficon TEK-Mate Refrigerant Leak Detector.

Elitech is a London-based company with over 20 years of experience in manufacturing safety equipment for the refrigeration industry. It’s an innovative company that currently has 80 authorized patents with 30 software patents. Some of its products include pressure gauges, air quality detectors, electronic refrigerant scales, temperature controllers, and gas leak detectors. One of its high-quality refrigerant leak detector sensors is the Elitech ILD Advanced Refrigerant Leak Detector.

The sensitivity or accuracy of a detection instrument is its ability to locate the exact source of a halogenated refrigerant leak. Extreme sensitivity is used to detect small leaks, and detection tools with such a setting are capable of detecting all types of refrigerants you are working with. Typical sensitivity leak detectors are mostly used in household applications and can detect fewer halogenated refrigerants in comparison. 

An automatic leak detector can detect a leak faster than any other method. However, different models have different response times. Some take three minutes to warm up and six minutes to find the leak. Some high-end models have impressive speeds and can locate the leak within seconds of being powered on.  

Another thing to consider is the type of batteries that your electronic leak detector uses and how long the batteries last. Some units only last for a maximum of four hours while others can stay on for weeks. Some detectors drain the battery even when not in use. Ideally, a model with a rechargeable battery is the best gadget for long-term use. 

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The Inficon TEK-Mate is one of the most unique electrochemical sensors that can detect all types of refrigerants, including R22, R32, R507, CFCs, HFCs, and their blends. It features infrared sensor technology for accurate readings and operates on heated diode technology with a diode made of a ceramic substrate. Moreover, the gadget is fitted with a flexible probe for easy access to tight spaces. This gadget alerts you of any leaks with its visual and variable-intensity audible alarms.

It has an LED indicator that lights up when the unit detects a leak, and you can adjust the sensitivity of the gadget to find the exact leaking spot. It also has two sensitivity settings, low and high, and the LED light flashes faster when the gadget gets closer to the source of the leak. The unit runs on two rechargeable D alkaline batteries, and the sensor can run for 1,000 hours without draining the battery. This leak detector is ideal for small-scale and industrial use.

However, the unit’s sensor is highly sensitive and may pick up false readings from the environment. The alarm may go off unnecessarily, especially when used outdoors. Also, it’s made of a fragile carrying case that may easily break when dropped or when the unit ages. If it cracks at the battery compartment, the unit may stop working.

LotFancy is an affordable and compact refrigerant leak detector that operates on heated diode technology for fast leak detection. It allows you to adjust the sensitivity setting to match the task. It also has a flexible probe with a sensor at the tip. The sensor sucks the air into the housing and triggers an alarm once it senses a leak. The probe is made of stainless steel for durability and can reach all the nooks and crannies of your HVAC unit. 

The unit runs on four AAA size batteries or a six-volt direct current and has a dial on the body that allows you to adjust the sensitivity rating. Once turned on, the unit beeps consistently at a rate of two beeps per second, and it increases the frequency to 10 beeps per second when it detects a leak. The unit has a maximum sensitivity of 0.2 ounces per year and is ideal for household applications or in a hospital setting to detect Ethylene Oxide gas leaks.

A major drawback of the product is that it has an average sensitivity level and may not be accurate at finding a small leak spot. It may also beep constantly when it gets close to the leaking point but may not zero in on the exact spot. In addition, the gadget isn’t very durable and may stop working after only two years. The unit doesn’t come with batteries.

Use this versatile detector to sense all refrigerants. It has many features that help you do the job. The eight-bar LED shows the strength of the leak. There’s an audible beep indicator, too, and you can set the detector’s sensitivity level (low, medium, high). The rechargeable battery holds a charge for as long as 15 hours so you can work almost two full working days without a recharge. You can replace the battery yourself if you need a new one. The unit also works off a wall receptacle or a vehicle charger. 

The detector features either manual or auto zeroing. Auto zero works every two seconds until the leak activates the sensor. The hardshell carrying case is great to transport the detector and for storing it. The detector itself is ergonomic with attractive yellow and black colors. 

In some cases, though, the detector did not detect R134A refrigerant. Some users claim the audible beep is not loud enough.

Adjustable and highly sensitive, the Elitech Refrigerant Leak Detector is one handy diagnostic and detection tool. This device can pick up freon leaks and their triggers on all different types of refrigerants, including popular varieties like R22, R134A, R404A, and R410A. It even works on all types of halogenated refrigerants, including HFCs, CFCs, and blends. Reliable and well-rounded, you’ll be able to depend on this detector in countless settings.

In addition to all of this versatility, the Elitech detector is highly sensitive when it’s time to take readings. It delivers results within three seconds, and it warms up within six seconds. There are seven different adjustable sensitivity levels to choose from, including the lowest setting of 0.21 ounces per year. 

Audio and visual alerts help you detect a leak easily. With an overall size of 9.02 x 2.56 x 2.56 inches and a weight of 0.45 pounds, it’s also quite light and compact to carry anywhere.

The Simbow Refrigerant Leak Detector is one of the best options you’ll find for halogen refrigerants. Able to detect and alert you to leaks in R11, R500, R134A, R404A, and other varieties, this tool works easily and automatically.

With this refrigerant leak detector in hand, you can adjust the sensitivity and even allow it to make changes automatically to suit different testing scenarios. Powered by a precise and ultra-low power consumption circuit, plus four AAA batteries, you’ll be able to use the tool many times without worrying about power. The internal sensor is also made for high sensitivity and designed to last for a lifetime. 

If it’s extra convenience you want, this detector has it. A dual color display shows you current battery levels, and the audio and visual alerts ensure you never miss a warning of any leaks. The only real drawback is the batteries you’ll need to supply — it doesn’t come with batteries, so you’ll have to have some on hand when it arrives. 

A: A refrigerant's main purpose in your HVAC system is to remove heat from the air. When there are insufficient levels of the refrigerant, your air conditioner runs longer to compensate, uses up more energy, and the components may get damaged in the process. Also, large leaks could be an environmental hazard, and it’s unhealthy to inhale large amounts of the refrigerant compound. 

A: The refrigerant comes pre-installed in the coils of your air conditioning system. The refrigerant could leak as a result of the normal wear of a system or a collision that results in damaged coils that leak the refrigerant. You should note that the air conditioner never uses the refrigerant, and it could circulate in the system for years if there's no leak. 

A: It depends on the sensitivity of the electronic leak detectors. Some models can only detect a handful of refrigerants, while others can detect CFCs, HFCs, HFOs, and blends of the

compounds. Manufacturers always indicate on the packaging the type of refrigerants the unit can detect. 

We choose the Inficon TEK-Mate Refrigerant Leak Detector as our top pick because it has a variety of user-friendly features, and its battery can withstand over 1,000 hours of use. It combines functionality with accuracy, and you don’t have to worry about buying a replacement sensor tip or batteries for a long time. 

Our budget-friendly pick is the LotFancy Refrigerant Freon Leak Detector. It offers real-time sensitivity readings and can tune itself to the most optimum state to detect a leak. 

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