F-Gas English Low GWP

All questions
HFC | Flammable | CO₂ | NH₃
Easy questions | Medium questions | Difficult questions

1

Easy

What is the base unit of mass in the International System of Units (SI)?


N
lb (pound)
kg
t

2

Easy

The refrigerant absorbs heat when…


…it condenses
…it freezes
…it is subcooled
…it evaporates

3

Easy

What does the GWP indicator mean?


The annual rise in mean air temperature caused by the emission of 1 kg of the gas
The ability of a substance to restore the ozone layer
Global Warming Potential: the climate warming impact of 1 kg of a gas compared with 1 kg of CO₂ (GWP = 1) over a defined time horizon, usually 100 years
Ozone depletion potential

4

Easy

What is the main function of a safety valve?


Discharges refrigerant when the set pressure is exceeded
Prevents the evaporator from freezing
It controls the oil level in the compressor
It monitors the moisture content of the refrigerant

5

Easy

What is the unit of pressure in the International System of Units (SI)?


Pa (pascal)
atm (standard atmosphere)
bar (gauge)
psi (pound per square inch)

6

Easy

How do system leaks affect compressor energy efficiency?


They affect only safety, not energy use
They improve efficiency because condensing pressure drops
No effect as long as the system still cools
Refrigerant loss reduces capacity and increases energy use (longer run times, higher superheat)

7

Easy

How does a dirty condenser affect the operation of the refrigeration system?


It improves efficiency
It lowers the condensing pressure
It has no effect
Causes an increase in pressure and energy consumption by the compressor

8

Easy

Why is adequate airflow through an air-cooled condenser important?


The lower the airflow, the lower the condensing pressure
It ensures effective heat rejection and low condensing pressure
It doesn't matter
It affects only noise

9

Easy

How does the presence of limescale in a water-cooled condenser affect performance?


It improves heat transfer
It lowers the condensation temperature
Impairs heat exchange and increases energy consumption
It has no effect

10

Easy

How do condenser leaks affect energy efficiency?


Have no effect
Causes refrigerant loss and a drop in efficiency
They improve efficiency
They lower the temperature

11

Easy

How important is the correct positioning of an air-cooled condenser?


It should be installed in a well-ventilated area with unobstructed airflow
It should be housed in a small room
It should be close to heat sources
It doesn’t matter

12

Easy

How does hot air recirculation affect the condenser?


Impairs cooling and increases energy consumption
It has no effect
It reduces the pressure
It improves efficiency

13

Easy

How does evaporator icing affect the system’s operation?


It improves cooling performance
Impairs heat exchange and increases energy consumption
It lowers the condensation temperature
It has no effect

14

Easy

How does dirt on the evaporator surface affect its performance?


Impairs heat exchange and increases energy consumption
It has no effect
It reduces the pressure
It improves efficiency

15

Easy

What maintenance task is crucial for the evaporator?


Reduced airflow
Lack of maintenance
Increasing the refrigerant charge
Regular cleaning and defrosting

16

Easy

How does superheat at the evaporator outlet affect efficiency?


It always improves performance
Excessive superheat reduces energy efficiency
It only causes a temperature drop
It has no effect

17

Easy

How do leaks in the evaporator affect efficiency?


These cause refrigerant loss and a drop in efficiency
Improves performance
Have no effect
Increase capacity

18

Easy

How important is correct expansion valve adjustment?


Ensures optimal evaporator charge and improves efficiency
It doesn’t matter
Causes leaks
It increases energy consumption

19

Easy

How does inadequate insulation of suction (or secondary-coolant) pipes affect evaporator performance?


It improves efficiency
It lowers the condensing temperature
It causes cooling losses and increased energy use
It has no effect

20

Easy

How does correct TEV adjustment affect system energy efficiency?


It ensures optimal superheat and improves efficiency
It causes leaks
It has no effect
It increases energy use

21

Easy

What happens if the superheat set by the TEV is too high?


It has no effect
Efficiency will drop because the evaporator is not being fully utilised
The refrigerant charge will increase
Cooling efficiency will improve

22

Easy

How do contaminants in the system affect the operation of the TEV?


Have no effect
They lower the temperature
They improve its performance
They can cause it to become blocked and reduce efficiency

23

Easy

What role does the filter-drier play in terms of system efficiency?


Removes moisture and contaminants, improving the system’s efficiency
It lowers the temperature
It increases the amount of refrigerant
It doesn’t matter

24

Easy

How does proper insulation of components (e.g. pipes near the TEV) affect the system?


It increases energy consumption
It causes leaks
It doesn’t matter
Prevents unwanted heat gains and improves efficiency

25

Easy

How important is it to check the operation of the condensing pressure control valve in the system?


It increases energy consumption
It causes a significant rise in temperature
It has no effect
Ensures operation within the optimum pressure range and reduces energy losses

26

Easy

How does the correct selection of a TEV affect energy efficiency?


Ensures the system is matched to its capacity and operates optimally
It increases the amount of refrigerant
It doesn’t matter
It lowers the temperature

27

Easy

What is the base unit of temperature according to the International System of Units (Système International d’Unités)?


°C
°R
K
°F

28

Easy

What is the superheat of refrigerant vapour?


The difference between the condensing temperature and the ambient temperature
The difference between the saturation temperature and the actual liquid temperature in the liquid line
The amount of heat required to evaporate a liquid
The difference between the actual vapour temperature and the saturation temperature corresponding to its pressure (expressed in K)

29

Easy

What is the compression ratio of a compressor?


The amount of refrigerant compressed per cycle relative to heat capacity
The ratio of suction pressure to discharge pressure (po/pc)
The ratio of absolute discharge pressure to absolute suction pressure (pc/po)
The ratio of discharge pressure to the effective capacity of the compressor (p/Vk)

30

Easy

What is the theoretical displacement (swept volume flow) of a compressor?


The volume of vapour drawn in per unit of time, determined by the compressor's geometry and speed (stated by the manufacturer, e.g. in m³/h)
A value expressed by the coefficient of performance (COP)
The volume of refrigerant flowing in one piston cycle under actual operating conditions
The volume of a single cylinder in cm³

31

Easy

What is the clearance (dead) volume of a reciprocating compressor?


The volume between the valve plate and the piston at bottom dead centre
The space between the underside of the piston and the crankcase cover
The volume between the valve plate and the piston crown at top dead centre
The space between the side of the piston and the cylinder