Chapter 9 Review

True or False? Compressor motors must be mounted inside the compressor housing.

• True

• False

Hermetic compressor motors are lubricated by _____.

• water carried by refrigerant vapor

• oil carried by refrigerant vapor

• cool air

• oil carried by liquid refrigerant

A(n) _____ compressor is a compressor that functions by changing the rotational movement of a crankshaft into a back-and-forth motion of the pistons within cylinders.

• open-drive

• reciprocating

• rotary

• scroll

True or False? In a scroll compressor, refrigerant vapor is compressed between two spinning scrolls.

• True

• False

In scroll compressors, refrigerant typically enters the scrolls from the _____ and exits out the _____.

• center; sides

• left side; right side

• right side; left side

• sides; center

The primary purpose of refrigerant oil is to _____.

• cool the motor windings

• help refrigerant flow more easily

• lubricate the mechanical parts of a compressor

• prevent refrigerant from forming clumps

Devices that specifically provide overcurrent protection for compressors are _____.

• circuit breakers and fuses

• crankcase pressure regulators

• discharge line thermostats

• head pressure controls

A thermal overload protects a compressor from overheating by opening _____.

• the compressor's power circuit

• a high-side relief valve

• a high-side service valve

• the motor’s windings

The main purpose of a metering device’s orifice is to produce _____.

• equal distribution of refrigerant

• a pressure drop

• smooth flow

• turbulent flow

True or False? The limited amount of refrigerant allowed to pass through a metering device into the evaporator is at a high pressure.

• True

• False