🔍 Key Concepts

• Hermetically sealed refrigeration/AC systems are factory-charged and not opened during normal maintenance • Difference between routine maintenance vs. major service/repair on a sealed unit • What parts of an AC unit are user-serviceable without opening the refrigerant circuit

💭 Think About

• Ask yourself: On a hermetically sealed unit, which tasks would normally require opening the refrigerant system or breaking the seal, and would those be considered routine? • Think about what shipboard personnel are expected to do on a regular basis to keep an AC unit efficient and clean, without special refrigeration tools or certificates. • Which option would most likely be performed frequently (e.g., weekly/monthly) instead of only when there is a serious problem or overhaul?

✅ Before You Answer

• Identify which options would break the hermetic seal or disturb the refrigerant circuit — those are usually NOT routine. • Consider which choice is a simple, repetitive maintenance task rather than a specialized refrigeration service procedure. • Verify which task could be done safely by typical crew without specialized refrigeration servicing equipment.