A Better Choice

A Better Choice for Auto Air Conditioning

Solstice™ yf refrigerant is environmentally compliant, safe, efficient and cost effective. It complies with the European Regulation for auto air conditioning.

Take a look at the strong points of Solstice yf refrigerant

Car OEMs

With Solstice yf refrigerant, car manufacturers can count on an international solution, since car makers in the U.S., Japan and Europe have already publicly declared that they will use the coolant going forward.

International car OEMs can use the same product for the European market in addition to all other markets they serve. The extra benefit of implementing Solstice yf refrigerant in a region where the European Directive does not apply is that a changeover to Solstice yf refrigerant results in reducing the global warming potential of each vehicle by 0.7 tons CO2 emissions.

Review all the benefits of Solstice yf refrigerant compared to the alternative refrigerant CO2 at a glance here:

Solstice yf refrigerant CO2 (R744)
Environmental Impact Lower lifetime GHG emissions than HFC-134a or CO2 20% more lifetime greenhouse gas emissions than Solstice yf refrigerant
Atmospheric Lifetime 11 days >500 years
Comparison to Current A/C Equipment Yes, it is a near drop-in solution for HFC-134a No; new high-pressure system required
Cooling Efficiency Comparable to HFC-134a in all climates Less efficient in hot climates where A/C is needed and used most
Ease of Implementation High; it is a near drop-in solution for HFC-134a Low; significant engineering and re-tooling required
Safety Safe for use in automotive air conditioning applications Safe for use in automotive air conditioning applications

Car Owners

Today, most people would not consider buying a car without air conditioning. A/C is now considered standard equipment and no longer seen as a costly or luxury option.

Auto A/C makes important contributions, not only to passenger comfort, but also to automotive safety. Driving in an overheated car – at 95°F/35°C – quite common in the summertime even in climates not considered to be hot – the driver‘s response time is reduced by up to 65 percent. In the case of an emergency stop, this can make the crucial difference between a crash and the safe operation of the vehicle.

A/C also contributes to auto safety in cold or moist conditions, as it contributes to defogging the windshield and ensures an unobstructed view of the road for the driver.

When you drive a car cooled with Solstice yf refrigerant, you can be confident that the refrigerant in your air conditioning equipment makes a substantially lower contribution to global warming compared to R-134a.

As a car owner, you’ll enjoy the same cooling performance you’ve come to expect from your air conditioning system. The only important change is that you can be assured your car has a much lower carbon footprint as a result of using Solstice yf refrigerant. Garage and repair shop staff are trained to handle refills and inspections, so you can be sure the refrigerant is being handled safely.

Aftermarket and Garages

Solstice yf refrigerant is the better choice for the aftermarket and garages compared to alternatives such as CO2. Based on LCCP analysis of major global cities, HFO-1234yf outperforms CO2 in all locations.

Solstice yf refrigerant CO2 (R744)
Ease of Leak Detection Easy, use in same equipment and techniques as today Difficult to find leaks; CO2 is present in background air
Service Equipment and Practices Similar to HFC-134a Higher pressures require different equipment and practices
Impact of Very Small Leaks Minor, lower pressure minimizes leak rates High pressure of CO2 makes even small leaks a problem
Impact of Charge Loss Low leak rates and ability to hold reserve charge reduce impact on performance Higher leak rates and limit on total charge due to pressure concerns increases impact of charge loss
Ease of Service Flexible hoses make it easy to replace hoses and components Stiffer hoses more difficult to work with in crowded engine compartments
Cost of Repair Parts Similar to HFC-134a CO2 components are more expensive than HFC-134a
Safety Can be used safely with proper practices and training Can be used safely with proper practices and training


The German special interest automotive paper “Auto Service Praxis” has reported about the filling of a new Subaru with HFO-1234yf.

Emergency First Responders

No one wants to experience a car fire but, when they happen, it helps to know that Solstice yf refrigerant poses no additional risk to first responders. The Material Safety Data Sheet recommends the same protection as for the current auto A/C standard, R-134a: wear self-contained breathing apparatus and protective suit. Honeywell recommends that emergency staff and professional rescue workers observe and practice their training when responding to car fires.

The German Association of Voluntary Fireworkers concluded in 2011:

  • The very low toxicity of both products (HFO-1234yf and R-134a) is comparable.
  • There is no higher risk with fire in closed buildings and parking buildings.
  • The usage of the refrigerant is safe for passengers and first responders.
  • The producers of the refrigerant will provide a Safety Data Sheet which will be based on comprehensive internal and external research. It will contain directions about the usage of breathing protective devices (not dependent on external air) and personal protection clothing.
  • The normal guidelines for assignments need to be observed as well as the guidelines for the prevention of incidents.

Solstice yf refrigerant is easier to inflame than R-134a, however, high energy is required (> 1 000mJ). Inflammation on a hot surface needs temperatures above 650° Celsius (conservative estimates: 550° Celsius).

TÜV * characterizes Solstice yf refrigerant as “very difficult to ignite in reality.”

Typically less than 1.3 lbs (600 grams) of Solstice yf refrigerant will be added to the automobile A/C system. The amount of hydrofluoric acid (HF) that could be formed in the case of a car fire is similar to the current situation with R-134a. To our knowledge no HF events have been recorded in the 50 years that fluorocarbons or chlorofluorocarbons have been used in car A/C systems.

In the event of an accident that includes fire, well-intentioned bystanders will not face additional risk posed by the possibility of HF formation. The amount of HF generated in a collision is not expected to be any worse than the other toxic gases produced by a burning car, such as carbon monoxide and cyanide gas. HF, by itself, is an extremely repulsive gas that a person cannot tolerate even in concentrations below the acute exposure guideline levels (AEGL-2). This will drive well-intentioned bystanders away from vehicles involved in a crash and fire. Since R-134a produces the same irritant effect when exposed to a car fire, we expect the same behaviors and reactions which occur with bystanders today.

*TÜV is the prestigious German association for technical assessment and a well-respected authority in the evaluation of technical advances.