R & AC RK 2

Subcooling occurs when the vapour

• removes latent heat from the refrigerant
• removes sensible refrigerant heat from the refrigerant
• has high latent heat
• has low latent heat

In a refrigeration cycle, the flow of refrigerant is controlled by ?

• compressor
• condenser
• Expansion valve
• Evaporator

Where does the lowest temperature occur in a vapour compression cycle?

• Condenser
• Evaporator
• Expansion valve
• Compressors

Choose the correct statement

• The absorption system is well known for its silent operation
• Automatic expansion valve is used to automatically control superheat
• Capillary tube can't be used for metering
• Refrigerant absorbs heat in the condenser

leaks in a refrigeration system using Freon are detected by

• halide torch which on detection produces greenish flame lighting
• sulphur sticks which on detection gives white smoke
• using reagents
• Smelling

Which of the following refrigerant charac- characteristics change constantly durin cooling cycle

• pressure and phase
• phase and flow
• temperature and pressure
• flow and pressure

What is the usual form of liquid oil particles in a refrigerant

• Fine fog
• Mist
• individual droplets
• all of the above

7.64. Pick up the incorrect statement

• lithium bromide used in vapour absorp- tion cycle is nonvolatile
• lithium bromide plant can't operate below 0°C
• separator is used in lithium bromide plant to remove the unwanted water vapour by condensing
• concentration of solution coming out of lithium bromide generator is more in comparison to

The domestic refrigerator uses following type compressor

• axial
• miniature sealed unit
• piston type reciprocating
• none of the above.

The lower horizontal line of the refrigera- tion cycle plotted on pressure-enthalpy diagram represents

• condensation of the refrigerant vapour
• evaporation of the refrigerant liquid
• compression of the refrigerant vapour
• metering of the refrigerant liquid