🔍 Key Concepts

• Compressor capacity control on multi‑cylinder reciprocating machines (what unloaders actually do) • Relationship between system load vs. compressor capacity and short cycling (rapid on/off) • Effect of thermostatic/expansion valves on system refrigerant demand and cycling behavior

💭 Think About

• Ask yourself: Is the compressor turning on and off rapidly because its capacity is too high or too low for the current load? • Which adjustment would make the compressor run longer per cycle but less often, instead of quickly satisfying the load and shutting off? • Which components are designed specifically to match compressor output to system load in a multi‑cylinder compressor?

✅ Before You Answer

• Identify which option changes number of active cylinders / compressor capacity, not just pressures or temperatures indirectly. • Check which action would reduce short cycling without repeatedly stopping the compressor manually. • Be sure the choice uses controls that are intended for capacity control, not just for changing refrigerant flow on the evaporator side.