CIRO System Operations & Maintenance 2

Question 1

What causes high discharge pressure in a compressor?

Accepted Answer

Dirty condensers, non-condensable gases, excessive refrigerant charge, high ambient temperature, or restricted condenser airflow

Answer

High discharge (head) pressure results from anything that impairs heat rejection in the condenser: fouled surfaces, air in the system, overcharge, restricted airflow, high ambient temperatures, or faulty condenser fans.

Question 2

What causes low suction pressure in a compressor?

Accepted Answer

Low refrigerant charge, restricted liquid line, dirty evaporator, low airflow across evaporator, or a stuck expansion valve

Answer

Low suction pressure indicates insufficient refrigerant reaching the evaporator: possible causes include leak (low charge), restriction in the liquid line, fouled evaporator coils, inadequate air/fluid flow, or expansion valve malfunction.

Question 3

What is the purpose of a vibration isolation system for compressors?

Accepted Answer

To prevent compressor vibration from transmitting to the building structure, piping, and equipment, reducing noise and preventing fatigue failures

Answer

Vibration isolators (spring mounts, rubber pads, flexible piping connections) prevent mechanical vibration from the compressor from damaging piping connections, building structures, and nearby equipment.

Question 4

What is a Management of Change (MOC) procedure?

Accepted Answer

A systematic process for evaluating and documenting any modifications to equipment, procedures, or materials before implementation to prevent introducing new hazards

Answer

MOC is a PSM requirement ensuring that any change to the refrigeration system (equipment modifications, procedure changes, material substitutions) is evaluated for safety implications before implementation.

Question 5

What is a Mechanical Integrity (MI) program?

Accepted Answer

A systematic program of inspections, testing, and maintenance to ensure that process equipment operates safely and reliably

Answer

MI programs include documented inspection schedules, pressure vessel testing, piping inspections, safety device testing, equipment maintenance procedures, and quality assurance for repairs and replacements.

CIRO - Certified Industrial Refrigeration Operator Practice Test

CIRO - Certified Industrial Refrigeration Operator Practice Test

CIRO System Operations & Maintenance 2