🔍 Key Concepts

• EPA regulations for servicing refrigeration and air-conditioning equipment • Safe methods for raising a large low pressure system to atmospheric pressure • Environmental rules on venting or adding refrigerants during maintenance

💭 Think About

• Which option would safely increase the system pressure without releasing additional ozone-depleting refrigerant into the atmosphere? • Which substance is commonly used as an inert, dry gas to help with leak checking or pressurizing systems? • Would adding heat be the primary EPA‑recommended method for non‑major repairs, or is there a more controlled, standard practice?

✅ Before You Answer

• Eliminate any choice that involves adding more CFC or HCFC refrigerant just to change pressure • Ask whether the method is environmentally responsible and commonly cited in EPA technician training • Consider which listed substance is typically used as a pressure-building or test gas, not a working refrigerant