Best Refrigerant Leak Detector (2022 Guide)

Worried about leaking refrigerant from your AC? You’re in the right place!

In this ProHVACInfo Guide you’ll learn the following

  • Why do HVAC Systems Need Refrigerant Gas?
  • What are the Dangers Associated With Refrigerant Leaks? (You might be surprised!)
  • What are the Different Types of Refrigerant Leak Detector? (Learn what you need before you buy)
  • What are the Benefits of Using a Refrigerant Leak Detector?
  • What to Look for in the Best Refrigerant Leak Detectors? (Learn what matters what what doesn’t)
  • Our Reviews of the Best Refrigerant Leak Detectors
  • And much more!
Inficon Refrigerant Leak Detector
  • Detects all CFCs, HCFCs, HFCs, and HFOs
  • 100 Hour sensor life
  • Includes rugged carrying case
  • Detects all CFCs, HCFCs, HFCs, and HFOs
  • 100 Hour sensor life
  • Includes rugged carrying case
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Elitech ILD-200 Advanced Detector
  • 3 Sensitivity levels
  • TFT screen leak detector
  • 10 Year sensor life
  • 3 Sensitivity levels
  • TFT screen leak detector
  • 10 Year sensor life
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Elitech WJL-6000 Leak Detector
  • Fast warm up time
  • Audible and visual alerts
  • Flexible probe
  • Fast warm up time
  • Audible and visual alerts
  • Flexible probe
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Elitech ILD-100 Infrared Refrigerant Leak Detector
  • Quick Operation
  • Rechargeable Battery
  • Easy to carry
  • Quick Operation
  • Rechargeable Battery
  • Easy to carry
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Mastercool 56100 Blue Raptor
  • Digital Signal Micro-Processor
  • Visual leak level
  • Variable frequency audible alarm
  • Digital Signal Micro-Processor
  • Visual leak level
  • Variable frequency audible alarm
View on Amazon

Why do HVAC Systems Need Refrigerant Gas?

HVAC systems such as air conditioning and refrigeration need to use a refrigerant gas in order for various parts of the system to function.

These gases, while important, can be difficult for individuals to understand on their own.

Most HVAC systems include a compressor, which compresses refrigerant gas and increases its pressure and/or temperature.

The increase in temperature causes the refrigerant to evaporate and turn into a gas.

The evaporated gas then turns into a vapor and enters the condenser, where heat is absorbed into coils that are filled with cold water or some other cool liquid. Liquid refrigerant now exits the condenser and goes to the expansion valve.

At this point, the pressure of the refrigerants in the system has been reduced.

This causes the refrigerant to evaporate even further, turning into a superheated gas that flows through the evaporator coils.

Heat is released into the atmosphere in this part of the process.

The coolness forces heat to be removed from its surroundings, cooling them down.

The refrigerant travels back to the compressor via tubing found throughout the entire system.

Here, the refrigerant changes back into a liquid state due to the pressure added by the compressor.

The cycle begins all over again as this liquid is forced through the condenser and through the evaporator.

The best way to understand what happens in an HVAC system is to imagine how water flows throughout your plumbing at your house.

When you turn on the hot water, cold water enters the pipes and is heated up by your faucet.

The pressure of this hot water is then increased with the assistance of the faucet, making it more forceful when exiting into different parts of your plumbing system.

The same happens in an HVAC system, but instead of water, a refrigerant gas is used.

This type of cycle is known as an absorption cycle due to the fact that heat is taken in by the evaporating liquid instead of being released into cool air.

The need for refrigerant gas exists because HVAC systems are designed to control temperature levels at the optimum level.

They do this by using a gas that absorbs heat, especially during warmer months.

This process is also necessary for other types of refrigeration techniques such as ice making and cooling drinks down in a refrigerator.

The only difference is the type of gas used to achieve this goal. Ice makers use ammonia while refrigerators utilize fluorocarbons.

HVAC systems need gas in order to work properly.

This is because they use the pressure of the gas to increase its temperature and evaporation level.

The system absorbs heat from different surroundings with each revolution that it makes, cooling down what’s around it for optimal comfort levels.

What are the Dangers Associated with Refrigerant Leaks?

Leakages of refrigerants pose many risks, such as:


Refrigerants are extremely flammable and easily combustible upon contact with ignition sources.

These risks can be mitigated by using high-quality hose fittings, compressor oil, and other gaskets.

This is especially important when working with refrigerants in a confined space where gas concentration can build up quickly in the event of a leak.

Environmental Impact

Refrigerants have been shown to have negative environmental effects including ozone depletion and the greenhouse effect.

This has led to a ban of many previously widely used compounds such as R-22 which is currently being phased out for more environmentally friendly alternatives.

Using high-quality hose fittings and ensuring all leaks have been repaired is a good way to keep damage to a minimum.

Health Risks

Refrigerants can cause dizziness, headaches, nausea, and in extreme cases can result in death when inhaled in high concentrations.

In order to quantify the danger of leaks, it’s important to understand which gas you are working with. R-22, for example, is 10 times heavier than air which creates a “pool” on the floor that can cause severe injury or death if stepped in by accident.

Following standard safety precautions will protect against these risks of leaks.

What are the Different Types of Refrigerant Leak Detector?

Having a high-quality detector on hand can help ensure leaks are discovered and repaired in the safest way possible.

While many common tools, such as an infrared sensor, can be used to detect gas leaks, some tools will provide more accurate results than others.

Let’s take a look at some of the best leak detectors for different applications.

Analog Refrigerant Leak Detectors

Analog detectors have a thin metal rod that’s attached to the handgrip.

A small amount of liquid nitrogen is stored in this rod, and as you use it, the nitrogen is released and cooled.

As soon as this gas meets a hole, it turns into a solid. This can be detected by the handheld device through vibrations and sounds.

Digital Refrigerant Leak Detectors

These devices work differently than their analog counterparts, and they’re actually more effective at finding leaks.

The main difference with a digital device is that it doesn’t have a metal rod inside. Rather, there’s a tiny microphone in its place.

This microphone detects the sound waves produced when nitrogen flows out of a hole. It then sends out an alarm to tell you where the leakage is.

Capacitance Probes

These leak detectors use a small amount of refrigerant to energize a probe which causes the tool to emit an audible tone.

This signal changes pitch as leaks are detected. When used with an automatic leak detector, the system can detect very high-levels of gas and has a wide range of sensitivity.

Ultrasonic Leak Detectors

These tools use high-frequency soundwaves and are able to detect tiny leaks as low as 1/2 PSI (0.03 bar).

If air is used as the refrigerant, it can detect leaks down to 10 microns.

Corona Discharge Detectors

These leak detectors work by forcing air through an electrical field.

If gases are present in the sample, the current passing through the wire fluctuates, causing an alarm.

The downside being that this sensor cannot tell the difference between gases, and can even be triggered by the presence of certain chemicals, so there are often false alarms.

These units are known for their high sensitivity.

Heated Diode Leak Detectors

Heated diode detectors are highly sensitive devices that use two diodes operating at different temperatures to detect leaks.

Since hot spots form early in a gas leak, these hot spots produce a large amount of ions which in turn produces an early warning for the leak detector operator.

As the gas leaks out of the HVAC system, it enters the space between both diodes.

The hot diode lets some ions through because it is hot enough to break apart the molecules in the air.

Since cold air doesn’t have as much thermal energy, there are no ions produced by cold air.

This means that any ions that make it through the hot diode will indeed be due to a leak, and will consequently set off the alarm of the diode refrigerant leak detector.

What are the Benefits of Using a Refrigerant Leak Detector?

There are many benefits to using an electronic refrigerant leak detector that can go above and beyond the more traditional methods of checking for leaks.

A gas leak detector is a device that uses electronic sensors to detect refrigerants at extremely low levels, typically lower than what humans are able to smell.

As more states begin to focus on ozone-depletion and greenhouse gas emissions, the need for leak detectors is growing.

In days gone by, most people checked for leaking refrigerant by spraying soap and water on the components of the system to check for bubbles.

It was a very visual way of checking, but overall not too accurate.

After the invention of high sensitivity electronic and analog refrigerant leak detectors, pinpointing the location of leaks became much faster, resulting in less environmental damage through lost gas.

An electronic refrigerant detector can not only detect a leak quicker than traditional methods, but it could also save time and money in the long run as well as help businesses stay compliant with current environmental regulations impacting their industry.

Incorporating an electronic gas detector into an operation is also much more efficient than using other tools to pinpoint the location of a leak.

There are numerous benefits associated with analog leak finding technology in general, but there are even more specific advantages that come along with electronic gas detectors.

They’re not only lightweight and compact but can be used to find leaks indoors or outdoors, above ground or below.

They can even detect refrigerants in the presence of other gases, such as oxygen and carbon dioxide.

Read on to learn about some additional benefits that come along with using an electronic gas leak detector.

  • An electronic refrigerant detector can detect leaks faster than other tools or even human noses, solving the problem more quickly, and reducing the chances of environmental damage.
  • Many models offer a carrying case or a belt clip for improved convenience of use.
  • Electronic gas detectors are lightweight, compact & versatile.
  • Electronic refrigerant detectors provide benefits beyond traditional testing methods such as soap and water, and some can even detect other types of gases in the presence of a leak.
  • Electronic gas detectors are more accurate than traditional methods, and many models come with advanced sensors to further reduce chances of error.
  • Electronic refrigerant detectors can help you stay compliant with current environmental regulations as well as save time and money in the long run.
  • Many models are equipped with additional features, such as a backlit LED screen for easier viewing in dark areas & a vibration alert function to notify technicians of a leak’s presence.
  • Many models come equipped with an automatic shut-off feature to preserve battery life and increase convenience for technicians in the long run.

What to Look For in the Best Refrigerant Leak Detector

There are so many different kinds of gas leak detectors, it can be hard to figure out exactly what separates a good one from

Number of Detectable Gases

Some models are designed to specifically sniff out a single type of gas, while others are fitted with a sensor cable of detecting a wide range of gases, including CFCs HFCs HCFCs and more.

The most advanced gas leak detection units are even able to alert you as to the presence of other toxic or explosive gases beyond refrigerants.

Look for a detector unit that can provide you with a range of gas leak detection, this will help to increase the cost efficiency of your detector as it can then be used for multiple applications.


Wherever gas detection is concerned, you should never try to cut corners on maintenance.

This is why it’s so important to investigate the cost and availability of consumable parts for whichever gas leak detector you choose.

Many detectors have replaceable sensors, check that the ongoing cost of these parts is affordable, and be sure that you understand about sensor life before investing in a particular model.

Also be sure to choose a leak detector with a maintenance and calibration schedule that you can comfortably stick to. If you are only buying your gas leak detector for occasional use, you don’t want to buy one that requires frequent maintenance regardless of use level.

Ease Of Use

Ultimately, if you are not an HVAC professional, you will need to make sure that whichever model you buy has good ease of use.

Mistakes with gas can be fatal, so it’s imperative that if you’re new to leak detecting, you choose something that offers presets, and/or has simple, easy to follow instructions.

Fortunately, YouTube is full of tutorials for how to use many of the models included in this list, so if you get stuck you shouldn’t have any issues finding resources.


Detection units are often used in tight spaces and drops are inevitable. Pick a tool that is as durable as possible.

ABS plastic is common and is a great material for long term reliability.

Regardless, ensure that you pick something with at least a 1 year warranty.

Having at least a 1 year warranty will ensure that if anything fails while you’re getting used to the unit then the manufacturer will replace it.

Battery Type

There are of course pros and cons to replaceable vs. rechargeable batteries.

With replaceable batteries, it’s always quick to replace your power supply, and there is no degradation over time.

Of course the downside is that there is an ongoing cost associated with renewing the D cell batteries usually used by a gas leak detector unit.

On the other hand, some models are equipped with lithium ion rechargeable battery packs.

They are efficient and powerful, and convenient to recharge.

Of course, if you don’t have a spare, or the battery isn’t removable, you will have to wait to use your detector unit until it’s fully charged if the battery has died, which could potentially take hours, this can be a problem if you need to use your leak detector quickly.

When looking for the best refrigerant leak detector, be sure to weigh up whether rechargeable or replacement batteries are more suitable for your needs.

Sensor Type

There are numerous types of leak detectors on the market, all of varying sensitivity, but the two most common are the infrared refrigerant leak detector, and the diode refrigerant leak detector.

Which one is the best refrigerant leak detector for you depends on your use case.

Heated diode refrigerant leak detection devices are ideal for pinpointing the exact location of a very small leak, and as such are very accurate.

They do, however, require more maintenance as the probes are easily soiled by dirt and oil, and of course, the sensors have a limited lifespan.

On the other hand, an infrared leak detector is less likely to give false positive alerts for gases that you aren’t looking for as their sensitivity is finely dialed into the target gas.

Not only that, but the sensors tend to outlast those found on an equivalent diode refrigerant leak detector.

The biggest downside of the infrared leak detector is that the technology requires that you keep the probe constantly moving, which can make it difficult to detect a small leak.

Sensors all have a finite number of hours of continuous use that they can withstand before requiring replacement, so bear this in mind when choosing your unit.

Best Refrigerant Leak Detectors Reviewed

Stephen Marks

Stephen Marks

Stephen is an HVAC and home-repair enthusiast. He's here to answer any of your questions about HVAC!

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Stephen Marks

Stephen Marks

Stephen is an HVAC and home-repair enthusiast. He's here to answer any of your questions about HVAC!

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