Free CHP-5: HVAC Fundamentals Exam Practice Questions

Sample Practice Questions

Try these 10 sample questions from the CHP-5: HVAC Fundamentals Exam practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1Under the materials-of-trade exception in 49 CFR 173.6, what is the maximum gross weight of a cylinder containing a Division 2.1 or 2.2 material?

   1. A. 66 pounds
   2. B. 100 pounds
   3. C. 220 pounds
   4. D. 440 pounds

   Answer: C

   Explanation: The rule specifies "a cylinder with a gross weight not over 100 kg (220 pounds)". This is the cylinder limit, rather than the aggregate vehicle limit.

   Reference: 49 CFR § 173.6 — Materials of trade exceptions — § 173.6(a)(2)

2. 2Which pair of fixed reference angles is provided by the square head of the Starrett combination square?

   1. A. 30° and 60°
   2. B. 45° and 90°
   3. C. 60° and 120°
   4. D. 90° and 180°

   Answer: B

   Explanation: The instructions specify "a precision ground 90° square face and a 45° miter face." These are the two reference faces of the square head.

   Reference: The Starrett Combination Square — Introduction, Assembly & Applications — Page 1, Description and Components

3. 3An HVAC technician needs to coordinate equipment and vent penetrations through a roof. Which construction drawing is intended to show these roof features?

   1. A. A foundation footing detail
   2. B. An electrical panel schedule
   3. C. A door hardware schedule
   4. D. The architectural roof plan

   Answer: D

   Explanation: The NPS roof-plan checklist says to "Identify plumbing, Heating, Ventilation and Air Conditioning (HVAC) and electrical roof penetrations". The roof plan coordinates those features with the roof assembly.

   Reference: National Park Service — DB Construction Documents, Design Deliverables — DB Construction Drawings, Architectural Sheets, Roof Plan

4. 4Which statement distinguishes a specific chemical compound from a mixture?

   1. A. Its components retain independently variable proportions
   2. B. It must contain only a single element
   3. C. Its constituent elements occur in definite proportions
   4. D. Its composition depends only on container size

   Answer: C

   Explanation: DOE states, "The composition of a specific compound is always definite." Mixtures can vary in composition while retaining their components.

   Reference: DOE Fundamentals Handbook — Chemistry, Volume 1 — Module 1, Basic Chemical Laws, p. 31, compounds

5. 5Which occupancy is within the stated scope of ASHRAE Standard 62.2-2025?

   1. A. A transient hotel guest room
   2. B. A dwelling unit occupied by long-term residents
   3. C. A commercial office workroom
   4. D. An industrial process control room

   Answer: B

   Explanation: The published scope applies to "dwelling units in residential occupancies in which the occupants are nontransient." A long-term residential dwelling meets that scope.

   Reference: ASHRAE Standards — Titles, Purposes, and Scopes — Published Standard — Ventilation and Acceptable Indoor Air Quality in Residential Buildings, Scope, opening applicability paragraph

6. 6An HVAC service vehicle carries only ordinary materials of trade, with neither of the exceptions in 49 CFR 173.6(d) applicable. What is their maximum aggregate gross weight?

   1. A. 440 pounds
   2. B. 220 pounds
   3. C. 660 pounds
   4. D. 880 pounds

   Answer: A

   Explanation: Section 173.6(d) states that "the aggregate gross weight of all materials of trade on a motor vehicle may not exceed 200 kg (440 pounds)." The question excludes the listed exceptions.

   Reference: 49 CFR § 173.6 — Materials of trade exceptions — § 173.6(d)

7. 7Which combination-square attachment is specifically intended to locate the center of cylindrical work?

   1. A. The square head
   2. B. The protractor head
   3. C. The scriber alone
   4. D. The center head

   Answer: D

   Explanation: Starrett identifies the Center Head as a means of "accurately locating the center of cylindrical or square work." The other components do not provide that centering geometry.

   Reference: The Starrett Combination Square — Introduction, Assembly & Applications — Page 1, Description and Components, Center Head

8. 8Which drawing view is most directly suited to checking floor-to-floor dimensions and typical ceiling heights along a cut through a building?

   1. A. A floor plan
   2. B. A building section
   3. C. An exterior elevation
   4. D. A reflected ceiling plan

   Answer: B

   Explanation: The NPS Building Sections checklist includes "Floor to floor dimensions" and "Typical ceiling heights". A section displays the vertical relationships along the cut.

   Reference: National Park Service — DB Construction Documents, Design Deliverables — DB Construction Drawings, Architectural Sheets, Building Sections

9. 9In an oxidation-reduction process affecting a metal, what happens when its atoms are oxidized?

   1. A. They lose electrons
   2. B. They gain electrons
   3. C. They lose protons
   4. D. They gain protons

   Answer: A

   Explanation: DOE states, "Oxidation is the process of losing electrons". Electron gain is reduction. Proton gain or loss would change nuclear identity, rather than describe the oxidation-reduction process.

   Reference: DOE Fundamentals Handbook — Chemistry, Volume 1 — Module 2, Oxidation-Reduction Reactions

10. 10EPA guidance recommends evaluating nearby outdoor pollution before increasing ventilation. Why is that evaluation necessary?

    1. A. Outdoor air eliminates all indoor pollutant sources
    2. B. More outdoor airflow always lowers every contaminant level
    3. C. Outdoor pollution cannot enter a mechanically ventilated home
    4. D. Ventilation can bring pollutants from nearby outdoor sources indoors

    Answer: D

    Explanation: EPA says to evaluate ventilation where there are "outdoor sources of pollutants, such as smoke or refuse, nearby." Outdoor air quality affects whether increased ventilation will improve conditions.

    Reference: US EPA — Improving Indoor Air Quality — Improved Ventilation, paragraph on nearby outdoor sources