One method is to use a bubbly liquid sprayed around were a possible leak is to visibly be able to see the leaks location. Using this method does work but often requires lots of time, especially for small difficult to find leaks.
Also If a system has a very low charge the unit will need charged with Nitrogen to raise the pressure.
Another method to find hard to spot leaks is to use a leak detector that will detect refrigerant and notify the user.
Every HVAC tech will have their own favorite method of finding a leak. In my experience using both the soap method, florescent dyes, and leak detector method have their advantages.
In the past leak detectors were notoriously bad at finding a refrigerant leak but technology today has changed with many good ones available.
Refrigerant leak detectors vary in build and cost. What fits one technician often doesn’t fit another.
The best method to find the right leak detector that fits you is to read the reviews on forums, Amazon, or other sources from real techs in the field already using it.
Below is our picks for best HVAC Leak detectors with links to Amazon.
As always be sure to read the reviews on Amazon, forums, or elsewhere to be sure a unit is a good fit for you.
*This post contains affiliate links.
Our Picks for the Best HVAC Refrigerant Leak Detectors 2019
- Fieldpiece SRL8
- Yellow Jacket 69336 AccuProbe
- Elitech ILD-200
- H10 Pro
- Yosoo hld-100+
Fieldpiece Heated Diode Refrigerant Leak Detector – SRL8
Fieldpiece is a well known HVAC tool manufacture and builds the SRL8 refrigerant leak detector.
It is good unit that is used by many professional HVAC technicians.
It can sniff out most any refrigerant including CFCs, HFCs, HCFCs and other blends.
The unit works very well with HFC refrigerants such as R134a and R404a.
It is less sensitive to CFC refrigerants such as R-410A or R-22.
The Fieldpiece SRL8 is a great unit that is a good fit in any HVAC tool kit able to quickly find a leak on many systems.
Yellow Jacket 69336 AccuProbe UV Leak Detect
Yellow Jacket which is another well known HVAC equipment manufacture that makes many good tools.
The Yellow Jacket AccuProbe is also built for professionals to find refrigerant leaks on an HVAC system.
The unit has a lot of features, uses 4 AAA batteries and has a UV light at the tip.
The display will show a number 1-9 to indicate how big a leak is found.
The unit works by detecting changes in refrigerant. This mean that when using it move the unit away from the possible leak for a moment and back again.
Moving the unit around gives the best results when trying to find a leak.
The Accuprobe also features a three led UV light system.
It works with 395-415 nano-meter wavelength leak tracing dyes for use on systems that were either installed with or have had dye injected in past service calls.
The AccuProbe is a good unit that has helped many techs find and repair refrigerant leaks.
Elitech ILD-200 Advanced Refrigerant Leak Detector Halogen Leakage Tester Checker High Sensitivity Portable Case 10 Years’ Life 【3 Years Warranty】
The Elitech ILD-200 is built for the professional HVAC tech with a good warranty and made to last many years.
It also has many built-in features such as three sensitivity settings to help narrow in on a hole.
The Elitech ILD-200 is a great unit made for those who plan on working in the HVAC field for many years.
Mars H10 Pro Refrigerant Leak Detector Made By Bacharach
The H10 Pro is another top-end unit that has helped many HVAC techs find a leak.
The unit comes in a small case with nicely laid out controls and long sniffer.
It makes an audible tick and the tip has a light with both going faster the closer to a leak it is.
The unit is powered by a rechargeable battery or external DC adapter.
Yosoo Halogen Gas Freon CFC HFC Refrigerant Leak Detector HVAC R134a R410a R22a
This unit is cheap compared to the other leak detectors. The cost makes me a little wary of how well it would work in the field.
While it cant be compare to the top name-brand units it would be good in some scenarios, just don’t expect wonders.
LotFancy Refrigerant Freon Leak Detector for HFC CFC Halogen R134a R410a R22a R600a R290 Air Condition HVAC
LotFancy is a low-cost budget unit that while not as good as other units wold be good in some scenarios.
The tip is flexible to bend and move about to get in close to find small hard to detect leaks.
It has a light and beeps when a leaks is found.
While small and kinda cheap looking it does work. It is not meant as a professional tool but works well enough for those looking for a budget unit.
Best HVAC Refrigerant Leak Detectors Comparison Chart
|Name||Build||CFC / HFC||Type|
|Yellow Jacket AccuProbe||Professional||Yes||Handheld|
|Elitech ILD-200||Professional||Yes||Portable case|
What is a Refrigerant leak?
A refrigerant leak happens when an HVAC system has a hole in the unit somewhere.
All HVAC units use refrigerant in a cycle to heat or cool.
When an HVAC system has a leak the refrigerant can escape causing the unit to stop working correctly.
The leak will need to be found and sealed before new refrigerant can be put back in.
How Do You Check for Refrigerant Leaks?
A refrigerant leak can be found with a leak detector, dyes, or soap and water.
Often a combination of the three is used to help narrow down the leaking spot.
An electronic leak detector is the most common method since it can quickly pinpoint a leaking spot.
Dyed can also be used which are let into the system and leak out of the leaking location.
Soap and water while old school can still work well in many scenarios to find a leaking refrigerant location.
What Does a Refrigerant leak smell like?
Most people describe a refrigerant leak as a sweet chloroform scent.
It can also smell like oil and usually has an oily spot were the leak is located.
How Do Refrigerant Leak Detectors Work?
HVAC leak detectors use different sensor technologies to detect refrigerant.
Heated Diode units work when gases come in contact with the unit and produce a small electrical current.
Solid-State sensors use a metal oxide heating element that detects conductivity changes.
When gas is absorbed into the heating element it changes the conductivity which can be measured and detect gasses.
Ultrasonic sniffers identify sound waves that are emitted when gas escapes from a leak.
When gas is pressurized it generates a sound in the 25kHz-10MHz frequencies.
This sound can be listened for electronically and give a beep when detected.
Ultrasonic units can detect any type of gas but cant detect how much if the refrigerant or the amount there is.
How Do You Fix a Refrigerant Leak?
First, the leak needs to be found and location marked.
Once it is found the location can often dictate if the leak can be fixed.
If it has a bad solder point is located the joint can simple be re-soldered together.
Other locations can be more difficult for example the coils are often very hard to solder back together.
The main goal is to find the leak and then fix it usually with solder.
How is a Refrigerant Leak Tested?
After a refrigerant leak is fixed an HVAC vacuum pump is used to place a vacuum on the system.
HVAC gauges are used to measure the vacuum and see if it holds.
If the vacuum holds the unit is not leaking and refrigerant can be let back in.
Alternatively, Nitrogen can also be used to pressure test the system for leaks.
A Nitrogen tank is used along with HVAC gauges to pressurize the system.
If there is still a leak the Nitrogen will leak out and the leak needs to be fixed.
If no Nitrogen comes out the unit can be filled with refrigerant and put back into service.