ESCO A2L Refrigerant Transition and Retrofit Considerations 2

Question 1

When transitioning from R-410A to R-454B, which system component most commonly requires adjustment or replacement?

Accepted Answer

The expansion device (TXV or EEV)

Answer

The compressor motor windings

Answer

The copper line set and brazed fittings

Answer

The condenser fan blades

Question 2

Which A2L refrigerant is a single-component (pure) refrigerant increasingly used in new residential split systems as a lower-GWP alternative to R-410A?

Accepted Answer

R-32

Answer

R-454B (Opteon XL41)

Answer

R-466A

Answer

R-452B (Opteon XL55)

Question 3

What is the approximate GWP of R-454B compared to R-410A's GWP of approximately 2,088?

Accepted Answer

GWP of approximately 467

Answer

GWP of approximately 4

Answer

GWP of approximately 1,500

Answer

GWP of approximately 2,000

Question 4

When is it ever permissible to mix an A2L refrigerant with a remaining R-410A charge in a system?

Accepted Answer

It is never permissible to mix different refrigerant types

Answer

When less than 10% of the original charge remains in the system

Answer

When the system is still cooling adequately and no leak is present

Answer

When the manufacturer explicitly approves a compatible blend top-off procedure

Question 5

Why must technicians use recovery equipment specifically rated for flammable refrigerants when recovering A2L refrigerants?

Accepted Answer

To prevent ignition from spark-producing components inside standard recovery machines

Answer

To achieve faster recovery speeds required by EPA regulations

Answer

Because A2L refrigerants are corrosive and damage standard recovery equipment internals

Answer

Standard recovery equipment cannot reach the vacuum depth needed for A2L refrigerants

Question 6

What does 'temperature glide' mean in the context of zeotropic A2L blends like R-454B?

Accepted Answer

The difference between dew point and bubble point temperatures of a blend at a given pressure

Answer

The rate at which refrigerant temperature drops when released from a pressurized cylinder

Answer

The rate at which the refrigerant cools an occupied space during normal operation

Answer

The maximum safe operating temperature limit of the refrigerant blend

Question 7

After completing a retrofit and recharging a system with an A2L refrigerant, what safety step must be performed before returning the equipment to service?

Accepted Answer

Perform a thorough leak check to verify no refrigerant leaks exist before returning to service

Answer

Run the system at maximum capacity for 30 minutes without checking for leaks

Answer

Apply a flammable refrigerant warning label only if any leaks are detected

Answer

Allow the system to self-verify by monitoring operating pressures remotely