RSES Code Compliance 4 — Questions and Answers
Question 1: What is the maximum refrigerant charge allowed in a self-contained air-conditioning system installed in a public corridor under ASHRAE 15?
- It is based on the room volume and the refrigerant's RCL (Correct answer)
- There is no limit for A1 refrigerants
- 20 lbs regardless of refrigerant type
- 50 lbs for any HFC refrigerant
Correct answer: It is based on the room volume and the refrigerant's RCL
ASHRAE 15 limits refrigerant charge in occupied spaces based on the room volume divided by the refrigerant concentration limit (RCL).
Question 2: Under EPA Section 608, which action is specifically prohibited when servicing refrigerant-containing appliances?
- Using recovery equipment manufactured before November 15, 1993
- Knowingly venting refrigerants to the atmosphere (Correct answer)
- Purchasing refrigerants in containers over 2 lbs
- Mixing A1 refrigerants during recovery
Correct answer: Knowingly venting refrigerants to the atmosphere
Section 608 explicitly prohibits knowingly venting Class I and II refrigerants to the atmosphere during maintenance, service, repair, or disposal.
Question 3: What is the primary purpose of a fusible plug installed on a refrigerant receiver?
- To indicate when the refrigerant charge is low
- To relieve pressure by melting and releasing refrigerant if exposed to fire (Correct answer)
- To prevent overfilling of the receiver
- To seal the receiver against moisture ingress
Correct answer: To relieve pressure by melting and releasing refrigerant if exposed to fire
A fusible plug melts at a specified temperature when exposed to fire, allowing refrigerant to escape and preventing vessel rupture from pressure buildup.
Question 4: Under the International Building Code, what minimum clearance is required around refrigeration machinery for service access?
- 12 inches
- 18 inches
- 36 inches (Correct answer)
- The IBC defers to equipment manufacturer specifications
Correct answer: 36 inches
The IBC and IMC require a minimum of 36 inches of clear working space around refrigeration machinery to allow safe service access.
Question 5: A technician finds that a customer's R-22 system is leaking. Under current EPA rules, what must the technician do?
- Immediately convert the system to an approved HFC refrigerant
- Recover the R-22 and repair the leak; R-22 is still legal to use in existing equipment (Correct answer)
- Tag the system out of service permanently since R-22 is banned
- Vent the remaining charge and replace with R-410A
Correct answer: Recover the R-22 and repair the leak; R-22 is still legal to use in existing equipment
R-22 is still legal to use in existing equipment with reclaimed or recovered refrigerant; the technician must recover and repair per Section 608 rules.
Question 6: Which ASHRAE standard addresses energy efficiency standards for refrigeration systems and directly impacts code compliance inspections?
- ASHRAE 15-2019
- ASHRAE 90.1-2022 (Correct answer)
- ASHRAE 34-2022
- ASHRAE 62.1-2022
Correct answer: ASHRAE 90.1-2022
ASHRAE 90.1 sets energy efficiency standards adopted by most US building energy codes, governing minimum efficiency ratings for refrigeration equipment.
Question 7: What type of detector is required by ASHRAE 15 in a machinery room to activate emergency ventilation?
- Ionization smoke detector
- Refrigerant vapor detector set to alarm at the refrigerant's RCL (Correct answer)
- CO2 concentration detector
- Temperature sensor set at 120°F
Correct answer: Refrigerant vapor detector set to alarm at the refrigerant's RCL
ASHRAE 15 requires a refrigerant vapor detector in the machinery room that triggers emergency ventilation when concentration reaches the refrigerant's RCL.
RSES Code Compliance 4
What is the maximum refrigerant charge allowed in a self-contained air-conditioning system installed in a public corridor under ASHRAE 15?