Leak Detection

Top 5

Greetings ladies and gentlemen. Hope everyone is ready for the weekend. I certainty am after the week I had. I had every intention on working on another article over the course of the week but before I knew it Friday had arrived and the week was over. On top of that my Saturday and Sunday are completely booked with either yard work or family time. So, here I am on a Friday night just after ten o’clock working on an article.

Today’s post is a bit different then my others. Typically, when I do an article I like to write it myself and provide all of the details and sources myself as well. Over the course of this week I had a few contacts at Bacharach reach out to me. They had just completed a study on leak detection and they wanted to spread the word on what their study and what their findings were. If you are an avid reader of other HVAC or refrigerant news you may have already seen other websites such as CoolingPost.com do an article on this study.

A refrigerant leak is obviously never a good thing. If you’re a home owner it can mean an expensive repair bill to fix the leak and recharge your system. If you’re a business owner that expensive repair just increased ten fold. Now, imagine if you’re dealing with an industrial refrigeration system that has thousands of pounds of refrigerant in it. That bill just keeps going up and up. This is why it is so important to identify and catch refrigerant leaks before they get out of control. Typically, the quicker the problem is found the less money you will have to pay in repairs.

On top of refrigerant leaks being expensive they are also hugely detrimental to the environment. Obviously, it matters what kind of refrigerant you’re using in but more often then not the refrigerant leaking is either hurting the Ozone or is affecting Global Warming. refrigerant either. There was a story last month that involved a seafood company not correcting their leaking R-22 units. They were then fined by the Environmental Protection Agency for not following the Clean Air Act. Leaks are serious.

The problem though when dealing with refrigerant leaks is finding and identifying the leak. You need the right equipment and the right knowledge on how to find a leak but even in the best cases a leak can be difficult to find. In fact, there are instances where leaks can come and go making it that much more difficult to find. So, how can we improve this process? How can we help our customers before the leak gets out of control?


What Bacharach has done is they have recorded leak detection data from all over the world. Over three billion samples, yes three billion. That is a huge number and an amazing amount of data at their fingertips. The aim here is to aggregate all of this data and determine what exactly are the top five refrigerant leak types. I am a big fan of this type of thing as I am a data guy and love digging into the numbers and analyzing the results.

To show these results Bacharach has created a free webinar for anyone to watch. All you need to do is fill out a simple form of name, e-mail, phone and then the webinar pops right up. The video is twenty-five minutes but it contains a lot of great information. It is narrated by Jason Ayres, a veteran at the Bacharach company with over twenty years of experience.

It’s easy to see after just a few minutes of watching the video that these guys know what they’re talking about. If you’d like to watch the video then please click here to be taken to Bacharach’s website. Again, you’ll have to fill out a short form but it only took me a few seconds.


Just so you all know, I was not compensated for this post. I did enjoy a nice dinner with the Bacharach guys here in Kansas City, but that was more of a meet and greet then anything else. We enjoyed some of that famous Kansas City barbecue! I watched this leak detection video myself and thought that it was a great resources for those of you within the industry. Check it out if you’ve got some time over the weekend or if you’ve got a slow day at the office!

Thanks for reading,

Alec Johnson


Infrared refrigerant leak detectors are some of the most popular refrigerant leak detectors that are used by day to day professionals in the HVAC industry. Most green guys in the industry will buy one of the cheaper detectors on the market just to have one in their tool bag. Usually, it’s a heated diode detector that will have the sensor go out on them after working on a larger leak or after dipping the probe in water. (Yes, this happens.) Don’t even get me started on what kind a homeowner or do-it-yourselfer will purchase.

I am a huge fan of Infrared leak detectors for one reason and one reason only. Quality. These types of detectors scream quality and with quality comes long lasting and dependable tools. As I get older I’ve slowly come to realize that buying an expensive tool today is much better than replacing a shoddy tool again and again. Here’s the question though, how exactly does an Infrared detector work? What are the Pros and Cons of these types of products? Should you get an Infrared or should you look at maybe a Heated Diode or an Ultrasonic detector?

The How

Infrared detectors are quite a bit different than their heated diode competitors. With a heated diode they detect anything that contains Chlorine or Fluorine. When they detect a leak you can move the probe closer and closer until you have an exact pin-pointed location. This is what most techs and mechanics are used to in their day to day work.

Infrared refrigerant leak detectors find refrigerant by sampling an area in a slow an deliberate sweeping pattern. So, instead of moving your probe to the exact location you would sweep your probe back and forth or up and down until your alarm sounds.

While you can’t hold your probe still with an Infrared unit you will find, that after some re-training yourself, that you’ll be able to pin-point leaks even better due to the sweeping back and forth motion. The biggest advantage of Infrared detectors is that it will trigger the same regardless of what refrigerant it is coming across. This is quite a bit different when comparing to a heated diode that reacts differently depending on the type of refrigerant.

Pros & Cons

Jut like with everything else there are Pros and Cons to purchasing an Infrared refrigerant leak detector. Let’s dive in and take a look at what they have to offer:


  • The sensitivity levels on Infrared sniffers are top notch. Most of these models can detect leaks as low as 0.10 ounces per year. This is as good as it gets as far as sensitivity. I have yet to see any detector on the market today that goes under that magical 0.10 ounces per year number. Now, truth be told there are corona or diode models out there that do the same but there are much more benefits to an Infrared unit then just sensitivity.
  • You will notice that when shopping for an Infrared detector that the lifespan of a sensor is much much longer than your typical leak detector. While standard detectors on the market may have their sensors last for twenty, thirty, or fifty hours of work a Infrared detection unit will see it’s sensor last up to one-thousand hours. There are some units out there that claim their sensor will last for ten years. Imagine that, not having to change the sensor on your detector for ten years. You save yourself the hassle as well as the money. (Sensor replacement for other units can be as high as forty-dollars.)
  • Some users have stated that they had to relearn how to use an infrared detector when comparing to other more traditional detection methods like Corona Suppression or Heated Diodes. With the Infrared detection units you have to keep moving the sensor instead of letting it sit in one place. The reason this is necessary is the unit will zero itself out ever few seconds. The point of this to prevent saturation to your detector. So, if you’re in a tight or small room and there are multiple leaks it may be very hard to get a solid reading from your diode or corona reader not to mention you have the risk of overwhelming and damaging your detection sensor. With the Infrared though, since it zeros out ever few seconds, it will not be overwhelmed as it adjusts to the room and air around it and will look for higher concentrations of refrigerant allowing you to easily find the source of the leak.
  • As I said above, having an infrared detection unit may even negate the use of other methods as you’ll be able to track down exactly where the leak is using just your sensor. No more finding the general area and then spraying soap and water on it looking for bubbles. No more ultraviolet dye. With the infrared you should be good to go. Now, do keep in mind that there are always are surprises when diagnosing a unit and you very well may end up needing an alternative leak detection method in some cases. The point that I am trying to make here though is that the use of these other detection methods will drastically decline with the purchase of an infrared refrigerant leak detector.

The Cons

  • I mentioned at the beginning of my post that Infrared refrigerant detectors are top quality. Well folks with top quality comes top price. These types of units are the best detectors on the market today and you need to be prepared to pay that extra cash to own one. Most Infrared units are between three-hundred to four-hundred dollars a unit. Yes, I know it is quite expensive but the thing to keep in mind is the life span of this unit. If you’re a business owner with a whole bunch of techs under you then I could see why you don’t want to absorb the cost of these units, however if you are a tech who has to buy their own tools or an independent guy then I would highly recommend getting yourself an Infrared unit today. Forget the cost and just bite the bullet.
  • Every detector comes with a warranty, as they should. The reason I am putting warranties under the Cons category here is due to the length of the warranty and what most of them will uphold if there is a warranty claim filed. If you buy a unit you will notice that the warranty term is either one or two years. That is a pretty standard warranty claim for any detectors, even the cheaper ones. My concern is that if you spend all of this money on a top quality detector and for whatever reason you get a defective one but you are outside your one year warranty then you are most likely out of luck. Sure, you can try to call the company up and negotiate but they have all the chips in their corner at this point. If I’m going to be paying this much for a detector then I would expect at least a three to four, maybe even a five year, warranty.
  • The last con I can find on these units is a small one. It is a complaint about how you have to keep sweeping your sensor back and forth with an Infrared unit. I explained why this is necessary above but some users have complained that it is very difficult to do a sweeping motion in very tight or confined spaces. I could see this being an issue and maybe this is where more traditional detection methods could come into play such as dyes or a soap and water solution.

Our Preferred Infrared Detectors

Alright folks so we’ve gone over how these detectors work, the Pros & Cons, but now we need to review what we here at RefrigerantHQ recommend.

Whenever I recommend a product I always like to use the Good, Better, Best model. What is that? Well you see there are three different kinds of consumers or customers. There are the guys who want the cheapest thing there but still will work, the good; then there are the guys who want decent quality but they are a bit timid on the cost, the better; and then you have the guys who want the premium product, the best.

The problem here is that with Infrared detectors there really isn’t a low entry point or even a medium entry point. All of the comparable units are right around the same price and right around the same quality. At the time that I am writing this the three units that I would recommend are all right between three-hundred to four-hundred dollars. (Prices are subject to change at any time.) Instead of my usual approach of Good, Better, Best I am going to suggest to you the top three Infrared detectors on the market today. It will be up to you to make your decision from there. If you need some more input feel free to check out each product’s official RefrigerantHQ’s review by clicking on their links below.

Robinair 22791 Refrigerant Leak Detector

Robinair 22791 InfraRed Refrigerant Leak Detector

Product Review


Fieldpiece SRL2 (K7) Refrigerant Leak DetectorFieldpiece SRL2(K7) Advanced Refrigerant Leak Detector

Product Review


Inficon D-Tek Refrigerant Leak Detector

Inficon D-TEK 712-202-G1 Select Refrigerant Leak Detector

Product Review



In conclusion that is a brief synopsis of how the Infrared refrigerant detectors work, the benefits and drawbacks, and RefrigerantHQ’s recommended products. Thanks for reading and I hope that I was able to answer your question.

Alec Johnson


The heated diode refrigerant leak detector is quickly becoming the most common type of detector seen in the field today. Sure, there are other models such as Corona Suppression and Infrared but the good majority of tools out there are heated diode.

Here’s the question though, how exactly does a heated diode detector work? What are the Pros and Cons of these types of products? Should you get a heated diode or should you look at maybe an Infrared or an Ultrasonic detector?

The How

This type of detector works by heating the refrigerant and breaking the molecules apart. When the molecules are broken a positively charged Chlorine or Fluorine ion will appear. The heated diode will detect these ions and sound the alarm either audibly, visually, or both.

What this means is that a heated diode detector will be able to sniff out pretty much all refrigerants used today. Why? Well most refrigerants either contain Chlorine or Fluorine. Let’s take a look at some of the most popular refrigerant classes and types on the market today:

  • CFCs – Chlorofluorocarbons have been pretty much phased out from the world today due to the Chlorine that they contained. Chlorine was found to damage the Ozone every time it was released or vented. Popular refrigerants in this category include R-12 and R-502.
  • HCFCs – Hydrochloroflurocarbons are pretty much the same story. They were also phased out, more recently, due to the Chlorine that they contained. The most popular refrigerant in this category which I’m sure you have all heard of is R-22. (R-22 was the standard refrigerant for residential cooling for many years.)
  • HFCs – Hydrofluorocarbons are where things get a bit different. In an effort to save the Ozone Chlorine was removed from these new classes of refrigerants. The one constant chemical that remained though was Fluorine. (Remember, that’s the other chemical that heated diodes detect.) HFC’s are the most popular refrigerants in the world today and include the most common names such as R-134a, R-404A, and R-410A.  Chances are you if you are working on a unit it’ll have an HFC refrigerant.
  • HFOs – Hydrofluoroolefins are a newer classification of refrigerants designed in effort to replace the HFC refrigerants. Like their HFC sister HFO’s also contain Fluorine. While these refrigerants are still being developed in labs today by Honeywell and Chemours there are some you may see in real world applications already such as working on a newer automobile and finding that it uses HFO-1234YF instead of R-134a.

You may have noticed that each one of those classes of refrigerants contained one of the key chemicals: Chlorine or Fluorine. While most refrigerants have these two chemicals not all of them do.

It is worth noting that there is one class of refrigerant that your heated diode detector will not find and that is Hydrocarbons. Hydrocarbons are your natural refrigerants such as Ammonia, Propane, or Isobutane. If you’re a residential tech then you’ll probably never run into these but if you’re a chiller or a freezer tech then you probably have already run into these at a supermarket or cold storage warehouse. For these you will need a Hydrocarbon detector.

Pros & Cons

Jut like with everything else there are Pros and Cons to purchasing a heated diode refrigerant leak detector.


  • Heated diode sensors can be very sensitive even to the smallest of leaks. Some of the top models can detect leaks as small as 0.006 ounces per year. Try getting that detection level with a Corona Suppression model!
  • With this type of detector you can move the probe right to the very spot of the leak and hover over that point to detect very small leaks. Infrared detectors require you to be constantly ‘sweeping’ back and forth rather than resting in one single location.
  • The most highly rated leak detector by technicians is a heated diode. Yes, that’s right the H-10 Pro is a heated diode model.


  • The biggest con on these types of detectors are the life of the sensor. Most diode sensors will need to be replaced after only about one-hundred hours of operation. A comparable Infrared detector will see sensor life last for years.
  • If you are working in an enclosed area that is saturated with refrigerant you man end up overwhelming your sensor and shortening it’s life.
  • The heated sensor needs time to warm up before it can be used. Depending on the model this can take thirty seconds or over two minutes.

Our Preferred Heated Diode Detectors

Alright folks so we’ve gone over how these detectors work, the Pros & Cons, but now we need to review what we here at RefrigerantHQ recommend.

Whenever I recommend a product I always like to use the Good, Better, Best model. What is that? Well you see there are three different kinds of consumers or customers. There are the guys who want the cheapest thing there but still will work, the good; then there are the guys who want decent quality but they are a bit timid on the cost, the better; and then you have the guys who want the premium product, the best. The question you have to ask yourself before reviewing our choices below is what kind of consumer are you?

The Good

Signstek Refrigerant Leak DetectorSignstek Portable AC Refrigerant Halogen Gas Leakage Detector Tester with High Sensitivity for Home Use


The Signstek refrigerant leak detector is your bare bones heated diode detector. This tool is for the homeowner, the do-it-yourselfer, or maybe even a junior apprentice trying to learn their trade. This is a cheap but still a quality detector.

The Better

Inficon Tek-Mate Refrigerant Leak Detector

Inficon TEK-Mate 705-202-G1 Refrigerant Leak Detector, R22, R410A, R134A Detects


The INFICON Tek-Mate is a very common and high quality heated diode detector that I am sure that you will find in any HVAC shop. Most everyone knows the TEK-Mate name already and will swear by it’s accuracy. The best thing is that as I write this it is under two-hundred dollars. (Price is subject to change at any time.)

The Best

Bacharach H-10 Pro Refrigerant Leak Detector

Bacharach - H-10 PRO Refrigerant Leak Detector


I am sure most of you already knew what was coming before you even scrolled over the Bacharach name. Yes, it’s the H-10 Pro refrigerant leak detector. This thing is hailed as the best of the best out of any and all leak detectors by technicians, mechanics, business owners, and everyone else alike. This is a premium product just be ready to pay a premium price.


In conclusion that is a brief synopsis of how the heated diode refrigerant detectors work, the benefits and drawbacks, and RefrigerantHQ’s recommended products. Thanks for reading and I hope that I was able to answer your question.

Alec Johnson



You may have noticed by now but over the past month I’ve been on a leak detection kick. It seems like nearly every other article is about detection or detecting products. What can I say. That’s just how my mind works. When I get focused on something I go and go until I burn myself out. All that being said I’m sitting here writing another article on refrigerant leak detection. I predict another four or five article before I move onto a different topic…

There are many types of refrigerant leak detection methods available for technicians and mechanics to use today. Most of them you have probably have heard of and others may be completely new to you. But the questions you may be asking is what are all of the different methods out there today? What are the Pros and Cons? What kind of detection do we recommend? What is the best way to find a leak? Let’s find out!

Before You Start

First and foremost before you even think about starting with an electronic leak detector, ultra-violet, or whatever else you have in your arsenal I am going to suggest something that will save you a ton of time and effort. When you realize that your unit, or the customer’s unit, is low on charge and you suspect a leak the first thing that I would recommend is to do a visual inspection. Yes, it’s that simple. Just look at it. What’s that saying? Keep It Simple Stupid.Refrigerant Leak With Oil Example

Look at the unit up and down. Look at the liquid line. Look at the suction line. Look at the coils. Look at everything. Anything that may look corroded, worn out, or just an area that you suspect there to be a leak is your first stop. A red flag is when you see traces of oil. Oil is circulated throughout the refrigeration cycle along with the refrigerant so when you see oil on the outside of the coils, lines, or wherever then you know there is a problem.

When you identify the potential problem, or you at least have an idea where a leak is, then here is where I would suggest getting out your soap and bubble solution. I prefer the Nu-Calgon Spray Bottle. Sure, some guys will use their own homemade soap and water solution but with the store bought stuff you get the extra viscosity which allows the sprayed solution to actually stay on the desired surface. I’m sure some of you have your own recipes but I’ll stick with my pre-bottled stuff.

Spray the solution on the desired area then sit back and wait. Depending on the leak and conditions at the time you may begin to see bubbles quickly or you may end up waiting for a few minutes. Once you see the bubbles you can truly begin your diagnosis and repair. If you don’t see any bubbles after an extended period of them then it’s time to move on or to potentially pull out your electronic leak detector.

There is one more tip that I’d like to mention before moving onto the next topic. As you know most of the time when there is a leak it’s usually the coil. These can be sometimes difficult to visually inspect. Some techs out there will stick their gloved fingers in and gently feel around in suspected areas. They do this looking for one thing. When they pull their hand back they are looking for signs of oil on the tips of their gloves. If there is an oil residue then presto you’ve got your leak. That being said please note that I am not condoning shoving your hand into the blower, the fan, the lit pilot, or anything else. Be smart and be safe.

What About Electronic Leak Detectors?

You may have noticed by now that I have barely mentioned electronic refrigerant leak detectors. Why is that? Well folks I see electronic detectors as a last resort option. Detectors are meant to be a precise device. They are not meant to be swept across the entire unit inside and outside mindlessly. This takes up way too much time and effort. Hours could be wasted at a job going back and forth with your sniffer trying to find the mysterious leak.

The logical thing to do here is to do what I have said above. Use your eyes. Use your hands. Use your investigative procedures first before you get out the detector. Really think about where the leak could be occurring. Then, when you have an idea and you have a proposed spot where you think a leak is this is where you would get out your detector to narrow the search down even further. Like I said, it’s a precise instrument. You point where and if there is something it’ll move you closer to the culprit.

When you do begin using your electronic leak detector I would suggest moving your wand from a top to down motion on whatever section you are scanning. There are some guys who like bottom up  scanning. They do this because refrigerant is heavier than air and you’ll be able to detect refrigerant flowing down if there is a leak. My concern here is that by using this method you are not finding the source of the leak. You only end up finding where all of the down flowing refrigerant is going not where the leak is originating. The top to down method will alert you the moment it senses the beginnings of a leak. This is really a matter of preference but I wanted to point it out here.

Types of Electronic Leak Detectors

Before purchasing a detector we should identify what kind that you want, or better to say what kind you can afford. Now there are a few main types of detectors and they are: Corona-Suppression, Heated Diode, and Infrared. These detectors can range in cost from thirty or forty dollars all the way up to six-hundred dollars for a premium unit such as the H-10 Professional Leak Detector. (As a side note, the H-10 Model is one of the most beloved detectors on the market today.)

Bacharach H-10 Pro Deluxe HVAC Refrigerant Leak Detector

  1. The corona-suppression type of detector works by creating a high voltage corona in the sensing tip. When the corona senses refrigerant the device will sound an alarm. This type of leak detector is the oldest type and some models go all the way back to the sixties. (Yes that far!) Some guys love the tried and true tools like this, me I prefer something newer!
  2. The second type of leak detector is the heated diode. This type of detector works by heating the refrigerant and breaking the molecules apart. When the molecules are broken a positively charged Chlorine or Fluorine ion will appear. The heated diode will detect these ions and sound the alarm. The downsides to both of this type of detector, and the Corona Suppression, is that they can be overwhelmed if the refrigerant leak is too large. If the area is saturated with refrigerant then these alarms won’t be of much help and you may actually end up damaging your sensor and having to replace it.
  3. Infrared detectors work by drawing the air sample across an optical sensor that then analyses how much infrared radiation there is in that given area. The benefits of this technology is that the sensors last much longer,  they are less prone to false alarms, they cannot be overloaded in an area saturated with refrigerant, and they are great at finding those very small leaks that other detectors just won’t sense. The Infrared detectors are the premium types of detectors on the market. Expect to pay a pretty penny for these babies.
  4. Now, there is a fourth type of detector that has been around for a while now called the ultrasonic detectors. These detectors work not by detecting refrigerant but by detecting the noise the refrigerant would make when it is being leaked. When refrigerant is leaking out of a unit, hose, compressor, or whatever it creates an ultrasonic sound that is so high a human ear cannot hear. The best thing about this type of detector is that it reacts by pressure and not by volume of refrigerant. The downside of this type of detector is that at times it can detect other noises that are around you and that are not coming from the unit you are working on. This could be especially troubling when in a large commercial building or plant environment with other machines going on all around you.

If you were to ask me my opinion on what the best kind of detector to get then I am going to have to say Infrared each and every time. Sure, the price is higher but you get such better quality, amazing leak sensitivity, and an extremely long sensor life. (Some of these sensors last up to ten years!) My two favorite Infrared units on the market today are the Fieldpiece SRL2(K7) and the Inficon D-TEK 712-202-G1 model. 


What About Ultra-Violet?

Ultraviolet Dyes – This is an interesting way to find leaks especially on a unit that you know has a leak but you can’t quite pin point the exact location. This method works by having the technician adding the dye to the system and mixing it in with the lubricants/refrigerant. When the dye has been instilled in the system the tech then uses a black or blue light scanning the unit looking for signs of the colored dye coming out of the unit. There are a few downsides to this detection method that deters a lot of professionals from using ultraviolet dyes. The first is that it can take a significant amount of time for the dye to fully cycle through the system. That means there is a lot of sitting around and waiting. The second downside is that not all dyes on the market today are recommended by HVAC manufacturers. If you used the wrong dye over multiple times you could end up damaging or destroying the unit’s compressor and we all know that it is not a cheap repair.


Well folks that about wraps it up. As I said at the beginning of this article there are a variety of ways to detect, find, and diagnose refrigerant leaks. Rather you are a visual guy, a bubbles guy, or leak detectors or bust kind of guy make sure that you at least consider the other methods out there and give them a try every once and a while. I know it’s easy to get set in our ways but you may find that trying this new method may actually save you some time or help you find that evasive leak.

Thanks for reading folks,

Alec Johnson