When charging a vapor compression system operating with ammonia (NH3) refrigerant, the initial charge is introduced at_________________?
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Answer: C. high pressure side close to receiver
Explanation
The initial charge of ammonia in a vapor compression system is introduced into the high-pressure side close to the receiver. Charging into the high-pressure liquid receiver allows liquid ammonia to enter safely without pulling vacuum hazards. Standard safety protocols dictate specific charging ports to prevent hazardous chemical splashes during system maintenance. Ammonia systems operate under varying pressures requiring careful handling of toxic and flammable refrigerant properties. The liquid receiver stores excess liquid refrigerant downstream of the condenser before it reaches the expansion valve. Maintenance technicians follow strict industrial refrigeration codes when adding or replacing refrigerant charges.
Industrial cold storage plants containing large ammonia inventories require specialized training for charging procedures. Improper charging techniques can cause hydraulic lock or compressor damage in high-capacity refrigeration plants. Safety valves and ventilation systems must be active whenever technicians handle anhydrous ammonia charges. Introducing liquid refrigerant into the compressor suction port causes severe mechanical damage known as liquid slugging. The compressor delivery line contains high-pressure hot superheated gas, making it an unsuitable port for liquid charging. Charging at random locations throughout the cycle violates standard mechanical engineering and safety procedures.
- Subject
- Engineering
- Category
- Mechanical Engineering
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- —
- Difficulty
- medium
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