CIRO Study Guide Answers....pdf

Refrigerating Engineers & Technicians
Association




Answers to Questions in the CIRO Study Guide




January 2023 CIRO Study Guide Answers Page 1 Developed: 08/21/2012
Revision: 1 Last Approved: 08/04/2022
Last Reviewed: 03/27/2023 Approved by: Harry
Wilkins

, SAMPLE CIRO SCREEN 300 HP SCREW COMPRESSOR –
NH3 NORMAL CONDITIONS
SUCTION PRESSURE 32 PSIG SCREW COMPRESSOR MOTOR AMPS 295 AMPS
DISCHARGE PRESSURE 154 PSIG SCREW COMPRESSOR MOTOR VOLTAGE 480 VAC
OIL PRESSURE 55 PSID SCREW COMPRESSOR SLIDE VALVE 100%
POSITION
SUCTION TEMP 26°F CONDENSER WATER SUMP TEMP 75°F
DISCHARGE TEMP 171°F CONDENSED LIQUID TEMP 85°F
OIL TEMPERATURE 136°F CONDENSER OUTLET PRESSURE 151 PSIG
OIL COOLER – OIL INLET TEMP 171°F
OIL COOLER – REFRIGERANT 85°F
OUTLET TEMP
- THERMO SIPHON OIL COOLING
- CONDENSER OUTLET NOT SUBCOOLED
NOTES: POWER FACTOR IS 0.86 MOTOR TYPE IS 3 PHASE
MOTOR EFFICIENCY IS 93%
CONDENSER TYPE IS EVAPORATIVE

SAMPLE CIRO SCREEN 300 HP SCREW COMPRESSOR –
NH3 ABNORMAL CONDITIONS
SUCTION PRESSURE 32 PSIG SCREW COMPRESSOR MOTOR AMPS 339 AMPS
DISCHARGE PRESSURE 184 PSIG SCREW COMPRESSOR MOTOR VOLTAGE 480 VAC
OIL PRESSURE 55 PSID SCREW COMPRESSOR SLIDE VALVE 100%
POSITION
SUCTION TEMP 26°F CONDENSER WATER SUMP TEMP 75°F
DISCHARGE TEMP 192°F CONDENSED LIQUID TEMP 95°F
OIL TEMPERATURE 154°F CONDENSER OUTLET PRESSURE 181 PSIG
OIL COOLER – OIL INLET TEMP 192°F
OIL COOLER – REFRIGERANT 95°F
OUTLET TEMP
- THERMO SIPHON OIL COOLING
- CONDENSER OUTLET NOT SUBCOOLED
NOTES: POWER FACTOR IS 0.86 MOTOR TYPE IS 3 PHASE
MOTOR EFFICIENCY IS 93%
CONDENSER TYPE IS EVAPORATIVE

Answers related to this sample screen appear in boldface
red.




January 2023 CIRO Study Guide Answers Page 2 Developed: 08/21/2012
Revision: 1 Last Approved: 08/04/2022
Last Reviewed: 03/27/2023 Approved by: Harry
Wilkins