Chapter 6 LO6 Components In An Air Pump

Question 1

What does the evaporator do?

Answer 1

The evaporator takes in a liquid, called the refrigerant, at colder temperature than the air outside. It absorbs thermal energy from the air and transfers into a gas. This gaseous refrigerant is still at too low a temperature for use

Question 2

What does the compressor do?

Answer 2

The refrigerant in gaseous form is pumped through the compressor. There the gas is compressed, increasing the pressure and critically the temperature of the gas. The gas, now at sufficient temperature is pumped to the compressor.

Question 3

What does the condenser do?

Answer 3

The condenser transfers this thermal energy to the water being circulated through the heat exchanger. The water from the hot water tank is circulated from the tank to the heat exchanger and then back to the top of the tank at a high temperature. The refrigerant in the condenser loses thermal energy and starts to condense back into a liquid at high temperature. This refrigerant is now pumped to the expansion valve.

Question 4

What does the Expansion valve do?

Answer 4

The expansion valve allows the gaseous part of the refrigerant to expand, reducing its temperature and condensing fully into a liquid but now at lower temperature than the evaporator end of the system. It is now pumped to the evaporator for the process to continue

Question 5

Why will a pump not work if the refrigerant is pumped directly from the evaporator to the condenser?

Answer 5

As it has not cooled enough and would be a waste of heat. This is why it has to go through the expansion valve

Question 6

Process in a heat pump

Answer 6

Evaporator - Compressor - Condenser - Expansion Valve