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Whether you’re a professional HVAC technician, a serviceman, or a knowledgeable DIYer, a trusty refrigerant leak detector is a must-have tool in your toolbox. Detecting and fixing the issue within the refrigerant system is an important but challenging job that cannot be done without a proper tool.
To help you find the best refrigerant leak detector, we reviewed a couple of dozen of different devices. The result? Ten great-quality Freon leak sniffers that can help you get the job done quickly, easily and safely.
The Best Refrigerant Leak Detector
One of the most popular refrigerant leak detectors on the market, the Fieldpiece SRL8 detects all types of leaks, including all CFCs, HFCs and HCFsc, as well as blends. This heated diode detector is highly accurate and fast, and equally important to some, fully rechargeable (15-hour recharge). One a single charge, it lasts around two workdays, meaning even if you spent two entire days hunting leaks, this trusty little tool would still not let you down.
The Fieldpiece leak detector has a filter system that protects the sensor from moisture and other damaging contaminants. Speaking of the sensor, it’s connected to the body at the other end of the snout. It has three sensitivity levels – from 6.6 oz/yr to 0.1 oz/yr – so it’s definitely extremely sensitive, although more to some refrigerants than others. After every two seconds, the tool will automatically go to zero until a leak is found, but if you feel the need to set it to zero yourself, that’s possible too.
Three sensitivity levels; highly accurate and fast at detecting leaks
Fully rechargeable, 15-hour recharge, battery lasts two days
Manual or automatic zeroing
Filter system protects the sensor from harmful contaminants and moisture
Audible and visual alarms for leak detection and battery dying
Comes with a 9-inch flexible probe, 5 O-rings, 10 replacement filters
- Weight3.75 pounds
Affordable, simple but reliable, the LotFancy Freon leak detector is extremely easy to use. The simple design and ease of use, coupled with the ability to detect all halogenated refrigerants, makes LotFancy one of the top-recommended tools.
This AC leak detector can sniff out all kinds of halogen refrigerants. It has the maximum sensitivity of 6 g/yr, so it’s pretty sensitive and accurate, although certainly less than the Fieldpiece detector. Nevertheless, this budget-friendly tool has real-time sensitivity and can automatically adjust to the best optimum state for detecting a leak, saving you time and effort. When you turn it on, it will beep regularly at a slow frequency (2 beeps per second), but when it detects a leak, it will beep at a higher frequency (10 beeps per second). Using 4 AAA batteries, the detector has a tri-color screen that displays battery percentage.
Max sensitivity of 6 g/yr
Detects various halogenated refrigerants including CFCs, HCFCs, and HFCs
Uses 4 AAA batteries (not included)
Tri-color screen for battery percentage, a flashing light and tune for leak alarm indication
Automatic adjustment to optimum detecting state
Comes with flexible, 7.84” probe
- Weight6.4 ounces
Another budget-friendly and simple to use leak detector, Signstek is a must-have tool for all handymen, and an excellent back-up detector for HVAC technicians. Using the heated diode method for refrigerant detection, this small, lightweight tool collects air and heats it so that chlorine and fluoride ions are separated.
When Signstek detects a leak, the LED display flashes out and lets you know how severe the leak is across six different levels. Its maximum sensitivity is 0.1 oz/yr, or 3 g/rg, so it’s highly accurate. It has two working modes, which are continuous, and no limi with instant reaction time and 2 seconds of resetting time. Using 2 C alkaline batteries, this tool is not rechargeable, which is understandable considering the price. However, there is a battery indicator, a tri-color display which lets you know when it’s time to change the batteries.
Max sensitivity 0.1 oz/yr (3 g/yr)
Detects all kinds of halogenated refrigerants
2 C batteries, tri-color display for battery usage
LED display with 6-level leak alarm
14″ flexible, stainless steel probe
Real-time and reset time sensitivity adjustments, two working modes
- Weight1.37 pounds
Looking for an ultra-sensitive electronic leak detector? Check out Yellow Jacket’s Accuprobe UV leak detector which uses UV tech or an electrolyte sensor (or both at the same time!) to find HFC, HCFC and HFO refrigerants, as well as SNAP blends.
This highly sensitive and durable device is made in the U.S.A., which guarantees safety and quality for years to come. As mentioned, it uses electrolyte sensor, UV tech or both to sniff out all kinds of refrigerants, even the most difficult to detect, including R-134a, R-404A, R-407C, R-410A and 1234yf. This type of technology reduces heat, which should give the sensor longer life than is the case with more traditional heated diode detectors. The Smart Alarm LED shows you how serious a leak is using a scale of one to nine, where 1-3 is less than 0.1 oz/yr, 4-6 is 0.1 to 0.5 oz/yr, and 7-9 is more than 0. oz/yr. Other features include instantaneous response time, automatic calibration and reset to the given environment, microcontroller technology and battery indicator.
Highly sensitive leak detector, 9 sensitivity levels
Uses electrolyte sensor and UV technology
Smart Alarm LED display + audible alert that can be muted
4 AA batteries, 4.5 hours of continuous life, low battery indicator
Automatic calibration and reset to environment
Comes with a flexible probe
- BrandYellow Jacket
- Weight3.2 pounds
Another highly sensitive and reliable leak detector, the Inficon D-TEK Select uses innovative technologies to deliver enhanced accuracy and long life. This next-generation tool utilizes infrared technology, or rather infrared absorption sensing cell, to detect all kinds of refrigerants, including the newer blends. Equally impressive, the device’s sensing cell lasts approximately 1000 hours, which is around 10 times longer than the company’s previous model, D-TEK sensor.
D-TEK Select is sensitive to all refrigerants, including all CFCs, HCFCs and HFCs, and R-22, R-134a, R-404a, R-410a, R-507 (AZ-50). Minimum sensitivity is 0.1 oz/yr, or 3 g/yr, making it one of the most accurate, albeit priciest, leak detectors on the market. The price is justified though – because the sensor lasts a very long time and maintains sensitivity over time for consistent and reliable performance, we believe it’s worth it, especially for HVAC technicians.
Highly sensitive and quick, max sensitivity 0.1 oz/y
Uses infrared technology for enhanced accuracy and longer life
Detects all kinds of refrigerants, including the newer blends
Rechargeable NiMH battery, 6.5 hours of battery life
On-board diagnostics show charging status, warn of low battery or infrared cell failure
Comes with a flexible, 15-inch probe, spare filters, charger and carrying case
- Weight3.8 pounds
Made in the U.S.A. with quality materials and user-friendly control panel, the Yellow Jacket’s AccuProbe II leak detector is a good option if you’re looking for reliable, mid-price Freon sniffer. This device detects a number of refrigerants and comes with three sensitivity levels, as well as audible signals to help you pinpoint leaks easily and quickly.
The three levels are low, or 0.15 oz. (4.3 g)/y, normal or HCFC – 0.03 oz. (0.9 g)/y, and high, which is 0.06 oz. (1.7 g)/y. The sensor is conventional and has a service life over 300 hours, with minimal cleaning and no adjustments. The response time is instantaneous and, equally important, the device automatically calibrates and resets to the environment. As for batteries it uses, you’ll need 4 alkaline batteries which provide around 4.5 of continuous life. There is also a low battery indicator which shows when it’s the time to replace them.
Detects all refrigerants (HCFC’s, HFC’s and HFO’s), instantaneous response time
3 sensitivity levels: low, normal and high
Uses 4 AA batteries, has a low battery indicator
Automatic calibration and reset to environment
Comes with flexible, 17” probe and a soft case
- BrandYellow Jacket
- Weight1.6 pounds
Highly sensitive, accurate and reasonably priced, the Inficon Tek-Mate leak detector is the tool to have whether you’re an HVAC professional or a layman. Using a sensitive heated diode sensor, this device detects all kinds of refrigerants, including R22, R507, R32 CFCs, HFCs, as well as any blends.
The Inficon Tek-Mate is lightweight and portable, but also quite durable. Besides a highly sensitive electrochemical sensor, the device also sports a filter for protection, as well as a rugged flexible probe for those hard-to-reach areas. There are two sensitivity levels (low and high) and variable intensity audible signal, as well as flashing LED that helps locate leaks faster. Its minimum sensitivity is 0.25 oz/yr (4 g/yr), and the sensor has a whopping 1000 hours of use. It uses 2 D alkaline, rechargeable batteries.
Highly sensitive, 2 sensitivity levels
Detects all kinds of refrigerants
Uses 2 D alkaline batteries
Variable intensity audible and visual alarms
Filter system protects the sensor
Comes with batteries, flexible probe, extra filters and carrying case
- Weight3.1 pounds
If you’re looking for a reliable and affordable Freon sniffer, check out Robinair’s TIFRX-1A refrigerant leak detector. Using the new Microprocessor smart technology, this handy little tool accurately detects a wide variety of halogenated refrigerants.
The Microprocessor controlled circuitry along with digital signal processing monitor ensure the device senses leaks up to 2000 times per second. This makes finding refrigerant leaks fast and easy, which, coupled with the tool’s lightweight and ergonomic design, makes it perfect for carrying and working on inaccessible locations (the flexible stainless steel probe is 14” long). The features include variable frequency audible alarm, as well as constant power indication. As for sensitivity level, its maximum is a leak bigger than 0.4 oz/yr (11 g/yr). The tool operates on 2 C-cell batteries.
Uses Microprocessor technology, max sensitivity 0.4 oz/yr
Detects all kinds of halogenated refrigerants
Variable frequency audible alarm
2 C-cell batteries, constant power indication
Comes with a flexible, 14” stainless steel probe, batteries and carrying case
- Weight3 pounds
The Bacharach’s Informant 2 is a dual-purpose device that detects both refrigerants and combustible gases if you install the respective sensor. Thanks to its accuracy, versatility and lightweight design, it can be used for both residential and commercial purposes.
The Informant 2 has a long and flexible neck for detecting leaks in tricky areas, as well as sensors located at the tip for pinpoint accuracy. Its maximum sensitivity is 0.1 oz/yr or3 g/yr when held at leak source. With dual LED scales and internal speaker which can be muted, as well as instantaneous response time, this device is simple and quick to use. The detector uses 4 AA batteries and has a typical 4-5 hours run time.
Can detect both refrigerants and combustible gases (with a proper sensor installed)
Highly sensitive, max sensitivity 0.1 oz/yr
4 AA batteries
Filter protects the sensor from contaminants
Audible indicator with a mute feature, flashing probe tip
Comes with 5 filters, batteries and a hard carrying case
- Weight3.1 pounds
Last but not least on our list is the refrigerant leak detector by ATD Tools. Made in the U.S.A. to meet the new SAE J2791 standard, this device is reliable and durable, designed to sniff out all HFC’s, HCFC’s and CFC’s refrigerants, including SNAP blends. It’s also very reasonably priced and comes with a 2-year warranty.
The tool uses a relatively long life heated sensor (300 hours) and has 3 adjustable sensitivity levels, so needless to say, it’s pretty accurate and dependable. Importantly, the response time is instantaneous and the device automatically calibrates and resets to ambient levels, so there is very little to do manually. Operating on 4 AA alkaline batteries, it provides around 8 hours of continuous use.
Reliable and accurate, 3 adjustable sensitivity levels
Detects all kinds of refrigerants, including SNAP blends
Automatic calibration and reset to ambient levels, instantaneous response time
4 AA batteries, low battery indicator
Comes with a flexible, 17” probe
True mechanical pump
- BrandATD Tools
- Weight1.5 pounds
Best Refrigerant Leak Detector Buying Guide
Refrigerant leak detectors are undoubtedly some of the most useful and time-saving tools an HVAC technician could have. And while many of these devices were not particularly accurate in the past, today's refrigerant leak detectors are highly sensitive and reliable.
But with so many different products on the market, it may be difficult to find the best refrigerant leak detector for your needs. To help you with this task, we’ve not only compiled a list of 10 quality detectors, but also put together a handy little buying guide. We’ve also answered some of the frequently asked questions about refrigerant leak detectors, so stay tuned until the end!
What to Look for in the Best HVAC Leak Detector
To purchase a good-quality HVAC leak detector, one that is both highly sensitive and durable, it’s important to pay attention to several details regarding the tool itself. Before you make any purchasing decisions, make sure the device checks the following boxes.
- Detects a variety of refrigerants
While you may not need a device capable of detecting all kinds of refrigerants and then some, make sure the tool you intend to buy is actually capable of detecting the ones you usually work with. Generally speaking, because tools that detect a wide variety of refrigerants tend to cost much more than those that detect several refrigerants, it’s best to check your field applications and take your expertise into account to pick the right one. If money is no issue, definitely go for devices capable of detecting all common and uncommon refrigerants and blends.
- Works quickly
Time is money and you need a fast-working device if you’re going to reach different locations for attending leak complaints. Look for detectors with quality sensors, little warm-up time and instantaneous time response. Generally, top refrigerant detectors will cost more.
- Good battery and sensor life
A good-quality HVAC leak detector should last for as long as possible (at least several hours of continuous work time) before running out of battery power. How long the device will actually last, depends on the battery it uses as well as how often you use it. Ideally, you want a rechargeable device, or at least a model that runs on rechargeable batteries. As for sensor longevity – the longest-lived ones tend to cost more.
- Reasonably priced
More often than not, money affects the consumers' decisions the most. While it’s perfectly understandable to want to pay as little as possible, it should be clear that usually, the price does equate quality. That being said, there are many affordable models that are reliable and accurate, so if you’re going to use them only occasionally, definitely give them a try. If you’re a professional such as an HVAC technician on the other hand, you should probably invest in an ultra-sensitive and accurate device.
Why You Should Use an AC Leak Detector
As many of you will know, any refrigeration system depends on the refrigerant to work. When there’s a leak, the system is losing refrigerants, and with them, the ability to provide adequate cooling. In the case of a domestic system, this would be an air conditioner not working properly, and as a result, a warm house in summer even when the AC is running on max. For an industrial system, this can lead to food spoilage, and as a result, a negative impact on the business. So, when an HVAC technician is called to resolve a suspected refrigerant leak, the core of the problem are financial cost and discomfort.
But there is also the third issue, often overlooked but perhaps the most important of all: the greenhouse effect. Refrigerants have a major impact on the environment, so fixing the leaks as fast as possible is of utmost importance. This is why using refrigerant leak detectors is so important – they’re highly sensitive, easy to use and work quickly. Using any reliable model can help you determine where the system is leaking in a matter of a few seconds, meaning you’ll be able to repair the problem promptly, thereby restoring the system to its optimum efficiency.
Different Types of Leak Detection
While HVAC leak detectors are undoubtedly some of the most valuable tools to have, they’re far from being the only way to test the system for leaks. The most popular refrigeration leak detection methods are:
- The Soap Test: the simplest and easiest way to test a system for a leak is to apply some soapy water to a suspected leak. If there is one, you’ll see bubbles. Simple, yes, but quite useful when you only have yourself to rely on.
- Using UV Dyes: if you need a more reliable method than ‘soap test’, but don’t want to invest in an electronic leak detector just yet, get yourself a UV dye and UV light. All you have to do is add that UV dye to the system and use UV light to look for leaks. Beware though – UV dye can damage some systems.
- Using Electronic Devices: using a quality electronic leak detector is the easiest and most reliable method of them all. Most models can not only tell you where the leak exactly is, but specifically what refrigerant is leaking too.
Types of Freon Leak Detectors
There are three main types of Freon leak detectors: heated diode, corona suspension and ultrasonic. Let’s cover each type in detail, so you can determine which one is better suited for your needs.
- Heated Diode: the most common and popular leak detector type, heated diode detectors collect the air from the inspection area and heat it so that the molecules separate. The sensor (diode) then detects if there is any refrigerant in the collected air. If there is, the device alarms you with sound and/or light, depending on the model.
- Ultrasonic: newest of the bunch, the ultrasonic HVAC leak detectors sniff out refrigerants using sound. How does this work? It’s actually quite simple: all leaks let out similar sounds, which we cannot hear but our technology can. If the ultrasonic detector ‘hears’ a leak, it will alarm you instantaneously.
- Corona Suspension: oldest of the three, the corona suspension method works by using high-voltage corona on its sensor to sniff out any refrigerants in the air. If it detects a refrigerant, it sounds the alert. Super-simple but effective, although much less reliable than the newer technologies.
So there you have it: the oldest, the newest and the most common leak detector types. Which one is for you? While there is no single best leak detector, it’s no secret that the heated diode type is the most widely used by HVAC professionals. This is because this type of detector is highly sensitive and trustworthy, plus easiest to find. This is not to say that the other two types are no good – on the contrary, each type has its pros and cons, and refrigerant leak detectors are no different. Ultimately, it all comes down to your preferences.
Best Refrigerant Leak Detector FAQ:
Q: What is a leak detection test?
A: A leak detection test helps identify if there is a leak in a refrigerant system. Sometimes, a system will have physical defects that will make it leak gasses or liquids, causing the system itself to lose the ability to provide adequate cooling. The test will determine if there is such a defect and which refrigerants are being leaked.
Q: How Do Refrigerant Freon Leak Detectors Work?
A: The way that a refrigerant leak detector works depends on the type of detector. Halogen leak detectors draw air from the inspection area into a small pump. The refrigerant (if there is any) then passes through a halogen sensor and gets translated into an electrical signal. The signal is then amplified and read out.
Q: Is a refrigerant Freon Leak Detector reliable?
A: Today’s electronic Freon leak detectors are highly sensitive and therefore very reliable. Of course, exactly how sensitive a detector will actually be, depends on the type and model you purchase. Although there are dozens of reliable, cheap refrigerant (Freon) leak detectors available, it’s safe to say that if you want a device that is ultra-sensitive and detects a wide array of refrigerants, you’ll need to pay more.
Q: What Type of Refrigerant Will it Detect?
A: This entirely depends on the leak detector you purchased. Some devices can easily detect CFCs, HFCs and HFOs, as well as various blends, while others can detect only a handful of refrigerants. Before making any purchasing decisions, always check if the device you intend to buy can actually detect all common refrigerants.
Our Top Pick
The Fieldpiece SRL8, Heated Diode refrigerant leak detector is our No.1 choice. There are multiple reasons for this, but the most important ones are that this is a trustworthy brand and a reliable type of leak detector. Most HVAC professionals use the heated diode type detectors because they provide the most accurate results, and Fieldpiece SRL8 is no exception. Detecting all kinds of refrigerants, including CFCs, HFCs, HCFCs and blends, with 3 sensitivity levels (0.01 oz/yr to 6.6 oz/yr), this device is highly sensitive, accurate and dependable. Importantly, it’s rechargeable and lasts almost two full days on a single charge. There is a protective filter, an option for both automatic and manual zeroing and audible and visual alarms. Finally, the device comes with a flexible probe and 10 replacement filters, making it one of the best, if not the best refrigerant leak detector on the market.
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