Testy

F-Gas English Low GWP

Všetky otázky
HFC | Flammable | CO₂ | NH₃
Ľahké otázky | Stredne ťažké otázky | Ťažké otázky

1

Ťažká

What is the role of a suction liquid separator (also in systems with flammable or toxic refrigerants)?


It separates liquid from oil
It prevents liquid refrigerant from entering the compressor
It is used only to measure moisture
It heats the refrigerant before the evaporator

2

Ťažká

What is the function of an oil separator in systems using flammable or toxic refrigerants?


It prevents liquid from entering the compressor
Heats the refrigerant before it enters the evaporator
Separates oil from the refrigerant and facilitates the return of oil to the compressor
They are used solely to measure the moisture content of the refrigerant

3

Ťažká

Why are PFAS formed by the decomposition of certain F-gases (e.g. TFA from HFOs) problematic?


They are very persistent, accumulate in the environment (e.g. water) and may be toxic
They cause rapid cooling of the atmosphere
They are readily biodegradable
They are climate- and environment-neutral

4

Ťažká

Which statement about installing Schrader valves is correct?


Hydrocarbons leak through Schrader valves
All Schrader cores are suitable for all refrigerants
Schrader valves must not be used in R744 systems
When brazing the valve body, the core must be removed, then refitted and tightened to the correct torque

5

Ťažká

How does an undercharge affect the high-pressure side (without discharge pressure control)?


Discharge (condensing) pressure and subcooling will both be lower
Discharge pressure higher, subcooling lower
Discharge pressure lower, subcooling higher
Discharge pressure higher, subcooling higher

6

Ťažká

What is the benefit of adding helium as a tracer gas to nitrogen in a pressure test?


Its small atoms pass easily through leaks and are detected
It has a distinctive odour that helps locate the leak
It has a higher pressure than pure nitrogen in the same cylinder
It reacts with refrigerant residues, producing a visible colour change

7

Ťažká

What can be the effect of a relief valve lifting repeatedly?


The valve stays fully open permanently
The valve may not reseat tightly and its set (opening) pressure may decrease
The set pressure increases
The valve no longer opens

8

Ťažká

What is the relationship between the pressure (p) and temperature (T) of nitrogen at the start (1) and end (2) of a tightness test (p absolute, T in kelvin)?


p₂ = T₂/(p₁ × T₁)
p₂ = (p₁ × T₂)/T₁
p₂ = (p₁ × T₁)/T₂
p₂ = T₁/(p₁ × T₂)

9

Ťažká

Which parts of a refrigeration system should be given particular attention during a leak check?


Compressor and receiver connections, because the pressure is highest there
Only compressor connections, because they are the only parts subject to vibration
Only condenser connections, because the refrigerant is liquid there
Joints, valves incl. stems, seals, parts subject to vibration, connections to safety devices

10

Ťažká

Leak checks can be carried out using various methods. Which pair is correct?


Physical and chemical methods
Direct and indirect methods
Material quality control methods and electronic methods
Methods with and without quality control of supplies

11

Ťažká

To whom can leak checks of stationary refrigeration equipment containing F-gases be entrusted?


An employee appointed by the owner of the installation
Any leak-testing specialist
A natural person holding a certificate covering leak checks (A1, A2 within its charge limit, or E)
A person who has carried out such checks before

12

Ťažká

What conditions must be met to use UV dye for leak checking?


It is sufficient that introducing dye into the circuit is technically feasible
A UDT authorisation for pressure testing is required
Manufacturer approval of the method and a certificate covering breaking into the circuit
It is sufficient to have a UV lamp, dye and safety goggles

13

Ťažká

Which leak-checking methods are considered direct methods?


Pressure-change measurement and immersion in water
Nitrogen with tracer gas and pressure measurement
Vacuum test and foam solution
1. gas detection devices (portable or fixed leak detection system), 2. UV detection fluid or dye, 3. bubble/foam solutions

14

Ťažká

What do indirect leak-checking methods involve?


A visual and manual check and analysis of parameters: pressure, temperature, compressor current, liquid levels and recharge volume
Ultrasonic measurement
Leak detection with an electronic detector
Leak detection with UV dye

15

Ťažká

What does a vacuum (decay) test involve?


The pump runs continuously to hold the required vacuum for the test
With the pump running, you watch the vacuum gauge reading
After isolating the pump, you check whether the system pressure rises
The pump is restarted every time the system pressure rises

16

Ťažká

How often should leak tests be carried out on equipment containing 1.5 kg of R404A refrigerant (5.9 tonnes of CO₂ equivalent)?


At least once every 12 months.
On initial commissioning.
Only when servicing the unit.
Once every six months.

17

Ťažká

How often should leak tests be carried out on equipment containing 7 kg of R404A refrigerant (27.45 tonnes of CO₂ equivalent)?


On initial commissioning.
Once every six months.
At least once every 12 months.
Only when servicing the unit.

18

Ťažká

Under Regulation (EU) 2024/573, a leakage detection system is mandatory when:


the equipment operates in an enclosed space
the equipment contains a flammable refrigerant in any quantity
the charge is 100 kg or more of ozone-depleting substances
the F-gas charge of the refrigeration equipment is 500 t CO₂ eq or more

19

Ťažká

Which leak-checking method may NOT be used by a holder of a Category E certificate?


Checking with a foaming solution
Leak checking with a fluorescent dye introduced into the circuit
Measurement with a handheld electronic detector
Visual inspection

20

Ťažká

Within what timeframe must a leak test be carried out on a stationary refrigeration system after a leak has been repaired, in accordance with EU Regulation 2024/573 on F-gases?


Immediately after the repair.
At any time.
Between 24 hours and 1 month after the repair.
At the next periodic inspection.

21

Ťažká

How often must refrigeration equipment containing ≥500 t CO₂ eq of F-gases be checked if (contrary to Article 6) no leakage detection system is installed?


Every month
Every 6 months
Every 12 months
Every 3 months

22

Ťažká

What is the basis of the GWP values in Regulation (EU) 2024/573?


For HFCs (Annex I) – mainly the IPCC Fourth Assessment Report (AR4); for HFOs and non-fluorinated substances (Annexes II and VI) – the Sixth Assessment Report (AR6)
AR6 for all substances
Each Member State sets its own GWP values
AR4 for all substances

23

Ťažká

An air conditioner (not hermetically sealed) contains 2.5 kg of R410A (GWP 2088). How often must it be checked for leaks?


At least every 12 months (5.22 t CO₂ eq)
No checks required (below 3 kg)
Every 3 months
Every 6 months

24

Ťažká

When is labelled hermetically sealed equipment containing HFCs (Annex I) exempt from leak checks?


Always, regardless of charge
When it contains less than 10 t CO₂ eq, and in residential buildings also when it contains less than 3 kg of F-gases
Never – hermetically sealed equipment is always checked
When it contains less than 5 t CO₂ eq

25

Ťažká

Is a chiller containing 50 kg of R1234ze(E) subject to leak checks under Regulation (EU) 2024/573?


Yes – every 12 months, because its GWP is low
Yes – at least every 6 months (every 12 months with a leakage detection system)
No – the threshold is 5 t CO₂ eq and 50 kg of R1234ze is below 1 t CO₂ eq
No – HFOs are not subject to leak checks

26

Ťažká

In 2026, may an existing refrigeration installation using R404A (GWP 3922) be topped up with virgin refrigerant?


Yes – bans apply only to new equipment
No – only reclaimed or recycled R404A is allowed (until 1 January 2030)
Yes, if the equipment has a leakage detection system
Yes – the ban applies only to equipment ≥40 t CO₂ eq

27

Ťažká

After 1 January 2026, may an R410A (GWP 2088) air conditioner be serviced using virgin R410A?


Only with reclaimed refrigerant
Yes – the servicing ban for air conditioners and heat pumps covers F-gases with GWP ≥ 2500
No – the ban covers all refrigerants with GWP ≥ 750
No – the ban covers all HFCs

28

Ťažká

Since 1 January 2025, may a new single-split air conditioner containing 1.5 kg of R410A be placed on the market?


Yes, if the unit is hermetically sealed
Yes – the ban applies only to units >12 kW
Yes – the ban applies from 2029
No – single splits <3 kg with F-gases of GWP ≥ 750 are banned

29

Ťažká

From when is it prohibited to place on the market split air-to-air systems up to 12 kW containing F-gases with GWP ≥150 (unless required for safety)?


From 1 January 2029
From 1 January 2027
From 1 January 2025
From 1 January 2035

30

Ťažká

Which persistent atmospheric degradation product of R1234yf is classed as a PFAS?


Carbon dioxide
Ozone
Trifluoroacetic acid (TFA)
Carbonic acid