When can HFC-134a become combustible in a mobile air concditioning system?

HFC-134a (tetrafluoroethane) is generally considered non-flammable under standard conditions. However, it can become combustible if exposed to high temperatures, such as those generated by a fire or electrical fault, which may lead to decomposition and the formation of flammable byproducts. Additionally, if the refrigerant is mixed with certain substances or under specific pressure conditions, the risk of combustion may increase. Therefore, while HFC-134a is not inherently combustible, specific circumstances can create a risk.