The Risks of Hydrocarbon Refrigerant Blends
When the temperatures warm up, it's a good time to remind technicians and drivers about the dangers associated with hydrocarbon refrigerants being sold as cheap substitutes for R-134a and R-12
When the temperatures warm up, it's a good time to remind technicians and drivers about the dangers associated with hydrocarbon refrigerants being sold as cheap substitutes for R-134a and R-12.
Marketed under names like HC-12a, OZ-12, DURACOOL 12a, and EC-12a, these hydrocarbon blends may contain high quantities of propane, isobutane, and other highly flammable gases.
"These products are sold online and at flea markets as direct replacements for SNAP-approved refrigerants," says Gary Hansen, vice president of Red Dot Corp. Based in Seattle, Red Dot designs and manufactures heating and air-conditioning systems, components, and replacement parts for heavy trucks and other commercial vehicles.
SNAP (Significant New Alternatives Policy) is a U.S. Environmental Protection Agency program that evaluates a refrigerant's ozone-depleting potential, global warming potential, flammability, and toxicity. The EPA has banned hydrocarbons as a replacement for R-12 in motor vehicles. Many states have made them illegal.
"Many consumers aren't aware of the hazards these cheap hydrocarbon blends pose to themselves and technicians who service their vehicles," Hansen says.
Hydrocarbon blends are highly flammable and in a confined space may burn or explode in the presence of an open flame, spark, or cigarette. No vehicle manufacturer has endorsed or authorized the use of hydrocarbon refrigerants in its current-production A/C systems, according to Red Dot. They can degrade gaskets and hoses designed for R-134a or R-12, making leaks more likely. Use them and you'll void the warranty.
Technicians should check for A/C system leaks before making an inspection or repair that requires an ignition source (or may generate one). "Use well-maintained, properly calibrated tools to identify refrigerants and sniff for leaks," Hansen adds.
"If you service A/C systems, test for these refrigerants and educate your customers about the dangers of flammable hydrocarbon refrigerants so they know to avoid them," Hansen says. "If you operate a motor vehicle and notice decreased A/C performance, stay away from cheap 'substitute' refrigerants and contact a certified and experienced mobile HVAC technician. He'll have the expertise and equipment to diagnose the problem and address it."
For more information, the EPA has a web page devoted to questions about these refrigerants here. For a list of acceptable substitutes, click here.
More Maintenance

Maintenance in the Messy Middle Part 4: Renewable Natural Gas
The keys to running renewable natural gas as a fleet fuel depend on specialized technician training, rigorous inspection schedules and an understanding of high-pressure fuel systems.
Read More →
Mack Adds 'Lock & Leave' Feature to Simplify Over-the-Air Software Updates
Mack’s new OTA enhancement allows drivers to start eligible software updates, lock the truck and walk away.
Read More →
Maintenance in the Messy Middle Part 3: Biodiesel
Biodiesel can reduce emissions, improve fuel-system lubricity and use existing diesel infrastructure. But NACFE’s Messy Middle maintenance report says fleets must actively manage storage, cold-weather operation, filters and oil drain intervals to avoid problems.
Read More →
Rush Expands Gulf Coast Peterbilt Network With Louisiana Acquisition
The expanded Rush network gives fleets additional sales, service, leasing and collision repair support across Louisiana's major trucking markets.
Read More →
Is Your Parts Procurement Process Reactive or Proactive?
Ready to revamp your parts procurement process? Learn how now with “Strategic Parts Purchasing: A Process Checklist”
Read More →
Maintenance in the ‘Messy Middle’ Part 2: Renewable Diesel Fuel
NACFE's latest Messy Middle Powertrain Service & Maintenance report says renewable diesel gives fleets an opportunity to reduce carbon emissions without changing trucks, fueling infrastructure or maintenance practices. But technicians still need to understand several important operational differences.
Read More →
The Diesel Engine Enters NACFE’s ‘Messy Middle’
NACFE’s new Messy Middle Powertrain Service & Maintenance report says keeping modern diesel engines running now depends as much on software, diagnostics and data as traditional mechanical service.
Read More →
Wabash Trailers Recalled for Improperly Installed Underride Guards
More than 900 Wabash dry van trailers may not comply with the Federal Motor Vehicle Safety Standard for rear impact guards.
Read More →
DTNA Software Update Gives Truckers More Time Before DEF Derates Take Effect
The changes reflect EPA guidance aimed at reducing downtime caused by emissions-system faults while maintaining compliance requirements.
Read More →
New Agentic Predictive Maintenance Report Demonstrates How Degraded Aftertreatment Systems Waste Fuel
Questar analyzed a large mixed-class fleet and discovered it was wasting as much as $30 in fuel per vehicle, per day, because of mechanically degraded aftertreatment systems.
Read More →
