RSES Installation, Maintenance & Repair Procedures 2

Question 1

When installing a condensing unit outdoors, what minimum clearance is typically required from walls and obstructions for proper airflow?

Accepted Answer

24 inches on the discharge side, 12 inches on others

Answer

Condensing units require greater clearance on the discharge side (typically 24 inches) and at least 12 inches on intake sides to prevent recirculation of hot discharge air.

Question 2

During a compressor replacement, you discover the old compressor failed due to a flooded start. What maintenance step should be added going forward?

Accepted Answer

Install a suction line accumulator

Answer

A suction line accumulator prevents liquid refrigerant from entering the compressor during startup, protecting against flooded starts.

Question 3

What is the correct procedure when brazing a copper-to-brass fitting joint in a refrigeration system?

Accepted Answer

Use silver alloy filler with appropriate flux on the brass side

Answer

When brazing copper-to-brass, silver alloy filler (phos-copper works on copper but requires flux on brass) with appropriate flux on the brass side is required to prevent oxidation and ensure proper bonding.

Question 4

A technician is retrofitting an R-22 system to R-407C. Which oil change is required?

Accepted Answer

Polyol ester (POE) oil must replace mineral oil

Answer

R-407C is an HFC refrigerant that requires POE oil because it is miscible with HFCs, whereas mineral oil is not compatible and must be removed.

Question 5

When performing an oil change on a hermetic compressor, how is oil typically added to the system?

Accepted Answer

Through the suction service valve using an oil injector or pre-charged compressor

Answer

Hermetic compressors lack an external oil fill port, so oil is introduced through the suction service valve using an oil injector while the system is under vacuum.

(RSES) Refrigeration Service Engineers Society Certification Practice Test

(RSES) Refrigeration Service Engineers Society Certification Practice Test

RSES Installation, Maintenance & Repair Procedures 2