Refrigerant R1234YF Charge Factor

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When filling compressed-gas containers (return bottles, recycling bottles etc.) the applicable regulations, technical regulations and laws must be observed.
Overfilling of compressed-gas containers (return bottles, recycling bottles etc.) must always be avoided. Overfilled compressed-gas containers do not have a sufficient gas cushion to accommodate the liquid expansion caused by the effects of heat. There is a danger of rupture.
To ensure safety, make exclusive use of compressed-gas containers fitted with a safety valve.
Return bottles and recycling bottles must either be weighed on a scale or the volume must be ensured while filling so that the container specified permitted weight for filling is not exceeded. The maximum permitted capacity is 80% of the maximum refrigerant fill weight of the return bottles and recycling bottles specified fill weight or 70% of the maximum fill volume (charge factor, the respective smaller value always applies). Explanation: it cannot be determined if along with the refrigerant the return and recycling bottles were filled with refrigerant oil.
A reservoir must have space for vapor as well as liquid. As the temperature rises, the liquid expands. The space filled with vapor decreases. At a certain point, there will only be liquid in the reservoir. Beyond this, even a slight increase in temperature causes extremely high pressure to build up in the reservoir, because the liquid will continue to expand even though there is not enough space for it. The forces that result are strong enough to rupture the reservoir. To prevent a reservoir from being overfilled, the regulations regarding compressed gases specify how many kilograms of refrigerant may be added to a reservoir per liter of interior volume. Multiplying this charge factor by the interior volume gives the permitted capacity. The figure for refrigerant used in vehicles is 1.15 kg/liter.
Because contaminated refrigerant can have another density as clean refrigerant R1234yf always pay attention to the maximum permitted charge factor.