Why do the directions on Enviro-Safe 134a Replacement with Dye say "Do NOT Pull a Vacuum"?

Our US Department of Transportation has regulations on how much pressure can be in a can. Everyone wants the cheapest and best price on refrigerant. So, we use a 2Q can because it is a standard can that can hold 70 psi at 70 degrees F. If a system is a small system and not a dual air system, the small amount of air in the system will make our refrigerant with dye work correctly as hydrocarbons do not react to air. If you do take the Enviro-Safe 134a Replacement Refrigerant with dye and you do charge into a vacuum and charge by gauge readings, you are actually overcharging a system that can cause damage later. It would not allow for expansion room so when the system gets extremely hot, it can tear up a compressor. If you pull a vacuum and charge by weight (6 oz of ES = 16 oz of 134), normally your gauge reading will read low and your cooling isn't great. 

 

NOTE: This does not hold true for a larger system that has front and rear ac systems. Dual air systems MUST use Enviro-Safe Industrial 134a Replacement Refrigerant! This refrigerant allows a vacuum to be pulled. We would love for all of our customers to use Enviro-Safe Industrial 134a replacement as that refrigerant will allow everyone to pull a vac and gets the best cooling!