Off-highway use of R-1234yf

By Steve Schaeber, MACS Technical Editor (29-MAY-2019)

It’s been a few years since R-1234yf started showing up in passenger cars and light trucks, and while that market is getting pretty much built out by this point, so far we haven’t seen it being used in anything else. Reasons for this are regulation (there is no current US mandate for low-GWP refrigerants, although new legislation has been proposed recently), incentive (there are no carbon credits for HD use) and permission (EPA has not yet approved its use beyond Class 3 vehicles). But a group of off-highway equipment manufacturers and their Tier1 suppliers (represented by AEM, the Association of Equipment Manufacturers) have been working towards getting it approved.

And if their SNAP application is accepted by EPA, R-1234yf refrigerant may soon be allowed for use in newly manufactured off-highway work machines.

Given the higher cost of yf and lack of requirements, you might wonder why companies would want to switch. But there are a few reasons, the first having to do with the F-Gas quota system in Europe. It’s a complicated scheme (based on 2015 usage) designed to limit the amount of high-GWP refrigerant being imported and used in EU member states. For example, in 2016 and 2017 they only allowed 93%, and for 2018 the amount was reduced to 63%. The gradual phase down will reach 21% of 2015 sales by 2030. This makes R-134a more expensive and harder to get in Europe.

Also, these manufacturers are not country-specific, as most of them build machines for sale around the world. This not only applies to US companies manufacturing products here in the US for export to other countries, but includes those who build off-highway machines for US import. R-134a is costly and hard to get in some regions, and if allowed by EPA it would be much simpler to use yf. Likewise, US manufacturers exporting to certain countries that ban HFCs must ship their machines empty and complete the A/C charging with yf upon arrival (since they can’t legally do this stateside).

The first step towards the SNAP approval process took place in early May, with several AEM and MACS members attending a meeting at EPA Headquarters. Led by AEM (who represents segments of the off-highway industry including agriculture, construction, forestry, mining and utility equipment) the group reviewed the risk assessment they had been working on over the last several months for the first machine configuration, which was agricultural tractors over forty horsepower. Other machine types (each of which require separate SNAP applications) include:

• Agricultural tractors (under forty horsepower)
• Self-propelled agricultural machinery
• Compact, utility and turf equipment
• Construction and forestry equipment
• Compact construction equipment
• Mining equipment

Essentially, they are asking EPA for the option to use either R-134a or R-1234yf as the industry sees fit for a certain application, expecting that more people will be using low-GWP refrigerants in the future. They have also conducted a risk assessment focused on any potential hazards to the operator, which includes items like cabin size, charge amounts, high pressure cutoff switches, pressure relief valve location, evaporator and seal testing, etc.

At this point (June 2019) we’re waiting to hear from EPA about further application requirements which may need to be completed. If there are none and EPA says the application is complete, then yf will be allowed after a 90-day waiting period. Official approval won’t come until EPA publishes their next rule (which we expect later this year) and is likely to include certain use restrictions similar to those used on passenger cars. EPA will also prohibit retrofitting with R-1234yf, primarily due to R-134a evaporators not being certified for use with an A2L refrigerant.

Note: We’ve also learned that activities in Europe have begun for Class 8 trucks to receive what the EU calls “Type Approval” for using yf in those vehicles. Right now, they’re still using R-134a in over-the-road trucks like we are in the US, and to date there has been no SNAP application for Class 4 through 8 vehicles. When that happens, MACS will keep you posted at our www.macsw.org website. Thanks for reading!

Originally published in the July/August 2019 ACtion Magazine by MACS Worldwide.

©2019 Mobile Air Conditioning Society (MACS) Worldwide

For more information, please contact MACS at (215) 631-7020 or visit our website www.macsw.org

Photo Credit: Photo by Steve Schaeber on 3/24/2017 shows an AGCO RT100 tractor with a fully enclosed operator cab, working on a field in Winside, Nebraska. Even on cooler days, operators working inside cabs like these need air conditioning to help counteract the “greenhouse effect” that takes place inside the cab due to solar radiation and heat rising off the engine and drivetrain components.