313D Regulations, Codes, and Safety Standards 5

Question 1

Which section of the International Mechanical Code specifies the required access opening dimensions for HVAC equipment installed in attic spaces?

Accepted Answer

IMC Section 306

Answer

IMC Section 306 specifies access and service space requirements, including minimum opening sizes and clearances for equipment installed in attics, crawlspaces, and other confined areas.

Question 2

A technician discovers an unmarked refrigerant cylinder at a job site. According to EPA and DOT regulations, what must be done before the cylinder can be used or transported?

Accepted Answer

The cylinder must be labeled, and unknown refrigerants must not be used or blended into known refrigerant supplies

Answer

EPA and DOT regulations prohibit using unidentified refrigerants and require proper labeling; unknown cylinders must not be blended with known refrigerants to prevent contamination.

Question 3

Under current EPA rules, which types of refrigerants are classified as 'non-exempt substitutes' and may be subject to use restrictions under the SNAP program?

Accepted Answer

Refrigerants listed as unacceptable or acceptable with use conditions for specific applications

Answer

The EPA SNAP (Significant New Alternatives Policy) program evaluates substitutes and may list them as unacceptable or acceptable only under specific use conditions, restricting their application.

Question 4

What is the required minimum depth of a P-trap installed on a condensate drain line for an air handler with 0.5 inches of static pressure in the negative pressure section?

Accepted Answer

1 inch

Answer

The trap depth must exceed the static pressure to prevent air bypass; for 0.5 inches of negative pressure, a minimum 1-inch trap depth is required to maintain the water seal.

Question 5

According to NEC Article 440, what is the maximum rating of a branch circuit overcurrent device (OCPD) for an air conditioning unit if the nameplate specifies 'Maximum Fuse or HACR Circuit Breaker – 30A'?

Accepted Answer

30 amperes

Answer

NEC Article 440 requires that the OCPD not exceed the value marked on the equipment nameplate; if the nameplate states 30A maximum, the installed protective device must be 30A or less.

(313D) Residential Air Conditioning Systems Mechanic Certification Practice Test

(313D) Residential Air Conditioning Systems Mechanic Certification Practice Test

313D Regulations, Codes, and Safety Standards 5