HVACR dangers to avoid this summer

Working as an HVACR tech during the summer presents some very specific hazards. Beyond spending long hours outdoors in the heat, you could also work in cramped, hot environments with exposed power lines and hazardous leaking refrigerants. Here are a few dangers to look out for this summer and ways to avoid them.

Stay safe around power

Safety around electrical equipment is critical and since we’re in HVAC, it’s part of the job – especially during the summer. This is when AC systems are overtaxed and are prone to failure and burning out. When repairing these systems or replacing components like fan motors and compressors, be sure to turn the power off at the breaker, not just at the unit. This minimizes the risk of accidental shock. As a final precaution, using a meter with non-contact voltage sensing can confirm the system is deenergized. Also, whenever you come across an exposed wire, use your electrical test tools to ensure safety and tape it off.

Be careful with refrigerants

Recharging a system is a frequent job for techs, especially during the summer months. During a recharge, techs are often inadvertently exposed to hazardous chemicals by breathing them in or absorbing them through the skin. Minimizing this contact is essential. To ensure your safety, wear the correct protective gear like gloves and safety glasses, and follow all manufacturer recommendations. If you need to recharge a system, be sure to use A2L-compatible tools like the Fieldpiece MR45 – Digital Refrigerant Recovery Machine and the Fieldpiece VPX7 – 10 CFM Vacuum Pump. Both are designed to work with the latest refrigerants.

Have the right tools in your bag

To work safely this summer, start by working smarter. Wearing the correct protective gear is a great place to start. Make sure that your bag includes PPE, gloves, helmets, hard-toed boots, and other equipment to defend you from potential hazards. Also, ensure that your bag has all the tools that you need for every job. Trips back and forth to the truck or the shop cause unnecessary delays and extend your time on the job site. Packing the right gear reduces exposure to dangerous heat and other potentially harmful weather conditions.

Work smart. Be safe.

Paying attention to the dangers of working around electricity and refrigerants is important. That’s why you should keep all potential hazards in mind. Avoid or minimize any risk by coming to work prepared with the right equipment, HVACR test tools and protective gear to keep you safe through the summer months.


Four ways to stay safe during the summer heat

Now that it’s getting warm out, customers are going to be pushing the limits of their AC systems more. It also means techs expect to be spending more time working outside. Here are a few ways for everyone to stay safe while working in the heat.

Drink up

First, stay hydrated. A good rule of thumb is if you’re feeling thirsty, you’re already dehydrated. It’s recommended to drink water before working outside and then drink one cup, or eight ounces, of water or electrolyte-rich liquids for every 15 minutes spent working outside. Also, stay hydrated after work as well – especially if you work outside in the heat on a regular basis. One word of caution is to not drink more than 48 ounces of water per hour. This may cause a medical problem if salt in the blood gets too low.

Dress for it

If you’re going to be outside all day, you need to wear appropriate gear and clothing. This means wearing breathable, comfortable clothing that’s protective, lightweight, and light-colored. Dark-colored clothing absorbs heat from sunlight, and heavy clothing also traps heat and wears you down faster. If you’re able, set up an umbrella or shade tent over your outside workspace. Some umbrellas, specifically designed with magnetic bases, easily stick to outdoor HVAC systems, and eliminate the need for bulky or cumbersome stands. This relief from the direct sunlight makes a world of difference.

Take breaks

If you’re working outside all day, taking breaks helps prevent heat exhaustion and workplace accidents. Don’t just tough it out. Build breaks into your daily schedule to encourage you and your team to stay cool, hydrated, and rested. Also, by utilizing wireless system monitoring technologies, it’s easy to connect tools on an outdoor unit and follow its readings from a shaded area or from indoors. The latest wireless tech sends a signal up to 1000’.

Know what to look for

Sometimes, just taking precautions isn’t enough. It’s important to know what symptoms to look for in both heat exhaustion and heatstroke. With heat exhaustion, keep an eye out for heavy sweating, paleness, and muscle cramps. If you start to notice these, head to a cool place and drink some fluids. More serious symptoms can include headaches, nausea, vomiting and fainting. These symptoms should be dealt with immediately. If you have a rapid heart rate, high body temperature or become confused, you could have heatstroke. This is a dangerous condition that could result in seizures or loss of consciousness.

Be safe out there

To learn more about signs of heat exhaustion, check out resources like Mayo Clinic and Cleveland Clinic for more information. We hope these pointers help you and your team stay safe and cool all summer long. If you want other ways to work faster and smarter, explore our catalog of products at

Blog Tech Articles

Understanding A2L Refrigerants

In December 2020, congress passed the American Innovation and Manufacturing (AIM) Act and in 2021 the EPA introduced a rule mandating an 85% nationwide phasedown in high-global warming potential (GWP) hydrofluorocarbon (HFC) refrigerants by 2036. This phasedown will be accomplished in three ways:

(1) Phasing down production and consumption

(2) Maximizing reclamation and minimizing releases from equipment

(3) Facilitating the transition to next-generation technologies and low-GWP refrigerants through sector-based restrictions. Many of these lower-GWP refrigerants are considered mildly flammable with an ASHRAE Standard 34 designation of A2L.

The transition to next-generation refrigerant technologies is being aided by the EPA’s Significant New AlternativesPolicy (SNAP) program which approves the use of low-GWP refrigerant for specific uses. Many A2L refrigerants have already been approved by the EPA with many more approvals in the works.

The goal of this paper is to provide information on refrigerant classifications, the differences between refrigerants and the influences driving the shift away from traditional refrigerants to A2L refrigerants.

Refrigerant Classification

The ASHRAE Standard 34 classification table is designed to categorize refrigerants according to two primary factors: flammability and toxicity. Regarding flammability, refrigerants are tested and categorized by several factors including how much refrigerant per unit volume of air will support combustion, the amount of energy needed to initiate combustion, the amount of energy released from combustion, and the rate of combustion propagation. Toxicity designated as A or B is defined by the occupational exposure limit (OEL). Lower toxicity refrigerants (A) have an OEL of ≥ 400 ppm while higher toxicity refrigerants (B) have an OEL of <400 ppm). 7

To give you an example of the classification table use, the following describes various refrigerants and their classifications:

Class A Class B
A3 refrigerants such as R-290 Propane have a higher flammability and a lower toxicity. At present there are no known B3 refrigerants.
A2 refrigerants such as R141B and R-406A are flammable and have a lower toxicity. B2 classified refrigerants such as R-30 and R-40 are flammable and have a higher toxicity 8.
A2L classified refrigerants such as R32, R-454B, and R-1234yf have a lower flammability than A2 and lower toxicity. B2L classified refrigerants such as R-717 Ammonia 8 have lower flammability and higher toxicity.
A1 classified refrigerants such as HFC R-407C and HFC R-410A have no flame propagation and low toxicity 1. B1 classified refrigerants such as R-10, R-21 and the rather obscure R-764 sulfur dioxide 2have no flame propagation but higher toxicity.


Since A2L refrigerants are mildly flammable it is important to understand the characteristics of flammability and how they are affected by the HVAC environment. There are three important factors when understanding flammability.

  • Lower Flammability Limit (LFL): The concentration in air necessary to generate a flammable mixture.
  • Minimum ignition energy (MIE): The lowest energy required to ignite the flammable material in air or oxygen found at a certain optimum (stoichiometric) mixture.
  • Heat of combustion (HOC): The amount of energy that is obtained from the burning of a volume of gas is measured in Btu.

LFL – Lower Flammability Limit

Mildly flammable A2Ls consist of HFCs, hydrofluoroolefins (HFOs), and also blends of these two synthetic refrigerants which have a high LFL, often 8 times higher than A3 refrigerants such as R-290 Propane. This means that a much larger concentration of A2L must be present to form flammable concentrations.  This is important when considering refrigerant leakage especially in enclosed spaces. While a very low amount of A3 refrigerant or a low amount of A2 refrigerant in an enclosed space can be very dangerous, A2L refrigerants require a much larger amount of gas leakage to reach sufficient concentrations necessary for ignition.

MIE – Minimum Ignition Energy

A2L refrigerants have a significantly higher minimum ignition energy (MIE) which means it is harder to ignite than A3 refrigerants. Hydrocarbon vapors such as propane (R-290) can be easily ignited by many energy sources, even sometimes by the lower levels produced by static electricity.5 This can be orders of magnitude lower than the levels required to ignite the A2L refrigerants. Even gasoline has a much lower MIE than A2L refrigerants by almost a factor of 10! 6

HOC – Heat of combustion

Heat of combustion is the amount of energy released during combustion. The units of measure for HOC are expressed either in kilojoules per gram (kJ/g) or Btu/lb. Simply stated, you can think of HOC as the violence of the reaction when a gas ignites.A3 refrigerants like Propane have a very high HOC, on the order of 19,905 Btu/lb. whereas A2 and A2L have much lower values on the order of 2700-4400 Btu/lb. This means that while A2 and A2L refrigerants can, under the right circumstances, burn with veracity, they are generally not in the category of explosion hazard like you would find in A3 refrigerants.

What you may find interesting is that the HOC for an A1 refrigerant like R-410A is 2,800 Btu/lb. and a nominal A2L refrigerant such as R-32 has a HOC is 3,869 Btu/lb. Given a typical residential ducted split unit charge being ~ 15 lbs., there is essentially only about 24,000 Btu difference between the A2L and R-410A. This difference is equivalent in relative comparison to burning 3.4 lbs. of dry wood (about 2.5 feet of dry 2 x 4) versus burning 1.7 lbs. Duraflame™ wax fire log (about 38% of a single log.) 3,9

Flammability Summary

You can summarize refrigerant flammability into the ease of ignition, expansion or propagation of the flame, and the amount of energy release.9

  • Class 1 refrigerants have no propagation at 60ºC but may still be flammable at higher temperatures.
  • Class 2L refrigerants are “mildly flammable”, difficult to ignite with a relatively low energy release and low flame propagation speed.
  • Class 2 refrigerants ignite easily with a relatively high energy release.
  • Class 3 refrigerants ignite very easily and are potentially explosive.

Compared to A1 refrigerants, A2Ls have slightly higher flammability properties, and if burned, produce similar types and amounts of by-products (e.g. HF), and somewhat higher heat of combustion/fuel value. Flammability risks from A2L refrigerants will be mitigated by a variety of equipment design changes, applicable codes and standards, and technician training. The lower flammability limit of A2L refrigerants is very high, which means that a high concentration of refrigerant is needed to create a flammable mixture (ASHRAE 34). 9, 10

So How Does This Affect Me?

The move to A2L refrigerants is happening now and is likely to accelerate. Even though the EPA has issued their rules to move away from high GWP refrigerants to low GWP refrigerants as found in A2Ls, state and local legislation will still need to allow the use of these more flammable refrigerants. There are currently 25 states that allow the use of A2Ls either for air conditioning only or air conditioning and refrigeration. Many more states have legislation under review.

Since each state handles the code-making process differently, it is important to understand your local building codes for A2L allowance. Except for a few like Illinois and Texas, most states have a statewide code process.  For states without codes, legislation needs to pass guaranteeing the acceptance of A2L refrigerants approved by U.S. EPA SNAP throughout the state. Please refer to your state and local building codes for specific information on your situation.

The shift to more flammable refrigerants will require the appropriate equipment for installation and servicing. It is critical to make sure your test equipment is compatible with A2L refrigerants. At Fieldpiece, we have the products you will need to safely navigate this transition. The following Fieldpiece test tools have been deemed compatible for use with A2L refrigerants:

Product # Description Product # Description
MR45 Recovery Machine DR58, DR82 Leak Detectors
SM380V, SM480V Refrigerant Manifolds MG44 Vacuum Gauge
JL3KH6, JL3KR4, JL3PC, JL3PR, JL3RH Charge and Air Kit Probes SR47 Refrigerant Scale
VPX7, VP87, VP67 Vacuum Pumps




1 – An introduction to A2L refrigerants and their use in Refrigeration, Air Conditioning and Heat Pump applications, FETA 2017,

2- Refrigerants Codes & Standards in Canada 2018,

3 -A2L Terms You Should Know

4 – A2L and A3: the better you know them, the better you use them,(Class%20A3%20and%20A2L).

5 – What Are A2L Refrigerants and Why Do We Need Them?, C-11869 (7/22), Chemours

6 – MIE Minimum Ignition Energy, Thorne & Derrick International,

7 – ANSI/ASHRAE Standard 34-2010, Designation and Safety Classification of Refrigerants. Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers. 2010-07-01. ISSN 1041-2336

8 – ANSI/ASHRAE Standard 34-2007, Designation and Safety Classification of Refrigerants. Atlanta, GA: American Society of Heating, Refrigerating and Air-Conditioning Engineers. 2008-06-26. ISSN 1041-2336

9 – AHRI Chapter 2. Chemical, Physical, and Environmental Properties of ASHRAE Standard 34 and ISO 817, chapter 2, pg 3

10 –


MR45: Refrigerant Best Practices

Smart recovery
If you’re recovering refrigerant, here are a few tips to help the process go smoothly. For starters, always wear the proper PPE. This includes protective gloves, goggles and shoes. Also, before you start the process, turn off the power to the system at the breaker.

Inspect the tank
The recovery tank is a pressurized vessel. Inspect it for damage or rust before using it. If you’re starting with an empty tank, pull it to a vacuum of 500 microns before beginning the recovery process to remove any particulates, moisture and non-condensable gasses from the tank. Using a scale, be sure calculate the maximum tank weight and only fill up to 80% of the maximum capacity.

Eliminate restrictions
One way to make recovery go as quickly as possible is to eliminate all possible restrictions for refrigerant flow. First, use a valve core removal tool to remove the valve cores on both the high-side and low-side service ports. Also, use a shorter, larger diameter hose with the core depressors removed. If you’re using a Fieldpiece MR45 – Digital Refrigerant Recovery Machine, inspect the mesh filter on the inlet port to be sure it’s clear of debris. Another way to increase overall flow is to connect the discharge hose to the recovery cylinder at the vapor port. This eliminates the resistance of the internal dip tube that’s connected to the liquid port.

Flip your tank
Regardless if you’re recovering into a container that already has refrigerant in it or not, flip it upside down before starting the recovery process using the vapor port. This ensures that the liquid that you’re putting into the cylinder comes in contact first with the liquid that is already in the tank. If not, it could flash into a gas as it enters. This keeps tank pressure down and speeds up the process.

Self-purge when done
When complete, don’t forget to self-purge all remaining refrigerant in the recovery machine before removing any hoses. To do this, turn the dial to self-purge and press start. This process automatically shuts off after removing all refrigerant from the line-set and the machine. Before disconnecting the discharge hose from the cylinder, be sure to close the tank valve first. This ensures you don’t lose any refrigerant from the tank. Also, be cautious when disconnecting the discharge hose as it will be filled with refrigerant.

Pick up an MR45
Weighing just 22 pounds, the Fieldpiece MR45 Refrigerant Recovery Machine is the fastest, lightest, and easiest-to-use recovery machine on the market. It has a large digital screen that shows the system pressure and the tank pressure throughout the entire recovery process—making recovery quicker and more efficient than ever. It’s powered by a durable, variable speed, smart DC motor, and has a convenient single-dial control and easy-access ports.

Recovery can be simple and fast if you use these tips and follow established safety procedures. Add the Fieldpiece MR45 – Refrigerant Recovery Machine to your arsenal at today and to see these best practices in action, go to Fieldpiece University and take the course while acquiring NATE credits!

Press Releases

Fieldpiece Instruments and SkillsUSA Announce First Round of Award Recipients for the 2023 #MasteroftheTrade Scholarship

Seven HVACR Rising Stars Gifted $2,500 Each to Fund Continued Career and Technical Education

ORANGE, CALIF. (May 16, 2023) — Fieldpiece Instruments, a leader in tool and test instruments for HVACR professionals for over 30 years, has awarded a total of $17,500 in grants to seven deserving students in the first round of its second annual #MasteroftheTrade Scholarship program. An additional $10,000 will be distributed to the six gold, silver and bronze medal-winning high school and college/postsecondary students that top the leader-board rankings of the National Leadership & Skills Conference in June.

The #MasteroftheTrade Scholarship, administered through SkillsUSA, aims to close the talent gap in the U.S. labor market for the heating, ventilation, air-conditioning and refrigeration trades by allocating funds to industry up-and-comers to use for college tuition fees or postsecondary HVACR technology program costs.

“With so many deserving applicant to the #MasteroftheTrade Scholarship, it was a challenge selecting the seven winners. We received many applications from across the nation submitted by bright, talented and motivated individuals pursuing a future in HVACR, which was extremely rewarding to see,” said Fieldpiece Instruments’ head of marketing, Diana Liem[J1] . “Congratulations to this year’s group of recipients; Fieldpiece is honored to provide these financial gifts as we continue to encourage industry growth through other initiatives like student discounts and in-depth skills enhancement for HVACR pros at all levels through Fieldpiece University.”

The seven accomplished SkillsUSA students named to receive the initial round of funding for Fieldpiece’s second annual #MasteroftheTrade Scholarship are:

  • Alabama: James Rogers, Alabama Army National Guard and Jason Rawls, Bevill State Community College
  • Massachusetts: Hunter Claflin, HVARC program at Blackstone Valley Regional Vocational Technical High School
  • Nebraska: Thomas Harling, University of Nebraska Lincoln
  • North Carolina: Irma Gonzales, Central Carolina Community College
  • Oklahoma: Ben Williams, East Central University
  •  Tennessee: Stacey Hicks, Chattanooga State Community College

On a mission to give back to the industry, Fieldpiece Instruments first introduced this scholarship program last year to help address the nearly one-hundred thousand unfilled HVACR technician jobs in the field reported in 2022. This important workforce is vital to ensuring energy is not wasted, food does not spoil and the comfort and safety of individuals are met on a daily basis. Pursuing a career in HVACR means having a consistent, well-paying job and offers professionals freedom, access to a hands-on work environment and the opportunity to create a lasting and positive impact on businesses, communities and the planet.

“SkillsUSA is proud to have had the opportunity to partner with Fieldpiece Instruments for the second year in a row,” said Chelle Travis, executive director at SkillsUSA. “Playing a small role in the career trajectory of eager young professionals is an honor and we look forward to seeing these rising stars continue to cultivate their skills and contribute to this critical workforce.”

To learn more, visit

ABOUT FIELDPIECE INSTRUMENTS: Fieldpiece Instruments is an innovative technology company focused on helping industry professionals do their jobs more easily, faster and better around the globe. It delivers on this promise through industry-leading devices with the broadest range of professional-grade tools and technology inspired by real-world application and field use. Fieldpiece is focused on serving the HVACR industry exclusively, enabling HVACR professionals to become Masters of the Trade. For more information, please visit, and be sure to follow Fieldpiece on Facebook, Instagram, YouTube and LinkedIn.

ABOUT SKILLSUSA: SkillsUSA is a nonprofit partnership of education and industry founded in 1965 to strengthen the nation’s skilled workforce. Driven by employer demand, SkillsUSA helps students develop necessary personal and workplace skills along with technical skills grounded in academics. This SkillsUSA Framework empowers every student to succeed at work and in life while helping to close the skills gap in which millions of skilled trade positions go unfilled. Through SkillsUSA’s Championships program and curricula, employers have long ensured schools are teaching relevant skills, and with SkillsUSA’s new credentialing process, they can now assess how ready potential employees are for the job. SkillsUSA has nearly 400,000 members nationwide in high schools, colleges and middle schools, covering over 130 trade, technical and skilled service occupations. SkillsUSA is recognized by the U.S. departments of education and labor as integral to career and technical education. It has served nearly 14.2 million members since 1965. For more information, visit:


Four Ways to Stay Ahead of the HVACR Curve

Whether you’re just starting your career in HVACR, or you’re a seasoned veteran who’s seen it all, staying ahead of the learning curve is important. As emerging heating and cooling technologies hit the market, more advanced tools are developed to service new and existing tech. Also, ever-changing regulations play a critical role in how we work with refrigerants and within building codes. Staying ahead is key to being successful in this industry. Here are a few ways to ensure you are always at the top of your game.

1: Learn the software

Now more than ever, our industry is driven by its available technology. Calculations that used to require utilization of multiple devices and then doing math in a notebook are now done instantly by a few wireless tools and an app on our smartphones. Much like learning how to use a set of analog gauges, mastering these digital tools is essential to keep up with today’s era of HVACR.

The Job Link® App is a good example. It connects with devices hooked to a system for real-time diagnostics from up to 1000’ away, and calculates critical values instantly. Other apps like this can schedule jobs, dispatch workers, create customer invoices and save important customer information to be referenced instantly during future service calls. These apps continue to advance and make everyday tasks easier and faster for companies and their technicians, so understanding and fully utilizing them is of growing importance.

2: Pick up the latest tools

Beyond the standard analog classics, today’s HVACR techs are experiencing a shift in available technology. Wireless tools like psychrometers and pipe clamps are continuing to increase in popularity and modern vacuum pumps are now being built with features and capabilities not available in previous years. Tools like these that increase the speed of your job without sacrificing accuracy are tools that equal time saved, and additional earnings. Proper understanding of these advancements in industry technology can help a tech earn more and learn more on each job.

3: Hit the books — and the blogs

Keeping up with the latest news by reading industry-related publications is another way to stay on the cutting-edge of our industry. Frequently check sites like ESCO and NCI for articles on new technology, emerging industry trends, and the latest HVACR news as well as training resources. Many manufacturers also have blogs to help customers stay up to date with new product releases and new developments in heating and cooling—sharing information about how to maximize the tools they’ve designed. These sources of industry knowledge give an insider’s view into what’s happening and what’s coming.

4: Scour the Web

Last, yet another way to continue expanding your knowledge is to tap into some of the many online resources for HVACR technicians. If you’re looking for free resources, there are a number of podcasts and YouTube channels out there dedicated purely to the HVACR industry. Check out the Advanced Refrigeration Podcast,HVAC School on YouTube, and other online resources like the ACCA’s Official Site. Fieldpiece University is another place to find courses that are focused on educating technicians about new product developments and best practices, while at the same time earning NATE credits.

These are a few ways to stay ahead of the technology curve and make yourself a better HVACR tech and a better employee. So why not use them to your advantage? Be a master of your trade!

If you want to pick up some new tools, or check out more blog posts, visit today.