HVAC Code Compliance 3 — Questions and Answers
Question 1: The EPA Section 608 regulations require that technicians recover refrigerant to what minimum level before opening a system with an appliance containing more than 200 lbs of refrigerant?
- 0 psig
- 0 inches Hg vacuum
- 10 inches Hg vacuum (Correct answer)
- 15 inches Hg vacuum
Correct answer: 10 inches Hg vacuum
EPA 608 regulations require recovery to 10 inches Hg vacuum for systems containing 200 lbs or more of refrigerant manufactured before November 15, 1993, and higher recovery for others.
Question 2: According to ASHRAE 15, a machinery room containing a refrigeration system must have what type of detector installed?
- Smoke detector only
- Carbon monoxide detector
- Refrigerant vapor detector (Correct answer)
- Combustion gas detector
Correct answer: Refrigerant vapor detector
ASHRAE 15 requires a refrigerant vapor detector in machinery rooms that activates an alarm and ventilation system when refrigerant concentration exceeds safe levels.
Question 3: Per the International Residential Code, what is the minimum headroom required in a space containing mechanical equipment such as a furnace or air handler?
- 6 feet
- 6 feet 6 inches (Correct answer)
- 7 feet
- 7 feet 6 inches
Correct answer: 6 feet 6 inches
The IRC requires a minimum 30-inch-wide clear pathway with 6 feet 6 inches of headroom to access mechanical equipment in attics, crawlspaces, and utility areas.
Question 4: Which listing organization's approval is typically required on HVAC equipment for code compliance in US jurisdictions?
- OSHA
- ANSI only
- A Nationally Recognized Testing Laboratory (NRTL) (Correct answer)
- State energy office
Correct answer: A Nationally Recognized Testing Laboratory (NRTL)
Mechanical codes require HVAC equipment to be listed and labeled by a Nationally Recognized Testing Laboratory such as UL, ETL, or CSA.
Question 5: Under NFPA 70E electrical safety standards relevant to HVAC, what is the minimum approach boundary for unqualified persons near exposed energized parts at 120V?
- Restricted approach boundary
- Limited approach boundary (Correct answer)
- Arc flash boundary
- Prohibited boundary
Correct answer: Limited approach boundary
NFPA 70E defines the Limited Approach Boundary as the distance unqualified persons must stay from exposed energized conductors to avoid electrical shock hazard.
Question 6: According to the International Mechanical Code, what is required when a condensate drain line from an HVAC unit is routed to a floor drain?
- Check valve
- Air gap (Correct answer)
- Backflow preventer with atmospheric vent
- Trap primer
Correct answer: Air gap
An air gap is required when connecting a condensate drain to a sanitary drain to prevent contamination of the condensate by sewer gases or backflow.
Question 7: Per the International Energy Conservation Code (IECC), what is the minimum duct insulation R-value required for supply ducts located in an unconditioned attic in climate zone 5?
- R-4
- R-6
- R-8 (Correct answer)
- R-10
Correct answer: R-8
The IECC requires R-8 insulation for supply ducts located in unconditioned attics in climate zones 3 through 8 to minimize energy loss.
HVAC Code Compliance 3
The EPA Section 608 regulations require that technicians recover refrigerant to what minimum level before opening a system with an appliance containing more than 200 lbs of refrigerant?