Study HVAC Exam from Delaware with 20 practice variants of 25 questions each, worked explanations, and original learning diagrams. The instructional bank is shared across states; geographical coverage means access to preparation, not a claim of a distinct local exam.

Overview
Exam Overview
Refrigeration fundamentals, heating, system measurements, and certification concepts.
Keep federal refrigerant certification and state or local contractor authorization on separate checklists. Study the exact refrigerant, temperature scale, and measurement location specified in a problem rather than assuming all systems use the same values.
Use Delaware government and agency directory to locate the relevant state agency. For a municipal trade credential, verify the city or county where the work will occur.
Official starting points
Scope
License Types
This page provides subject preparation. It does not establish the existence of a statewide license, authorize professional work, or issue a credential.
Structure
Exam Format
Each ExamsLib variant contains 25 single-answer multiple-choice questions. The official exam may use different question types, adaptive delivery, section lengths, and scoring. Use the current official candidate guide for those details.
Score
Passing Score
The ExamsLib practice target is 72%, or 18 correct answers out of 25. It is an instructional target only, not an official passing score or a predicted result.
Eligibility
Requirements
Keep federal refrigerant certification and state or local contractor authorization on separate checklists. Study the exact refrigerant, temperature scale, and measurement location specified in a problem rather than assuming all systems use the same values.
Requirements can change. Always confirm current licensing rules with the official state or local licensing authority before applying.
Cost
Fees
Each exam includes three free practice tests. Additional practice tests require a paid plan. Official application, examination, rescheduling, and credential fees are set by the relevant organization. Check its current fee schedule before registering; no official fee amount is asserted here.
Plan Ahead
Study Plan
Your preparation roadmap
- 01
Build your baseline
Take variants 1-5 without rushing. Classify every missed answer by topic and misconception.
- 02
Strengthen weak topics
Study the weakest topics and complete variants 6-10. Explain the reasoning aloud before selecting a choice.
- 03
Practice with a timer
Use the optional 40-minute practice timer for variants 11-15. Record time spent and distinguish knowledge gaps from rushed reading.
- 04
Review and consolidate
Finish variants 16-20. Rework missed questions from scratch and compare topic-level error patterns. Confirm official exam logistics separately.
Topics to focus on
- EPA 608 CertificationStudy EPA 608 for your HVAC exam. Covers Core, Type I, II, and III requirements, refrigerant regulations, recovery procedures, and common exam mistakes.
- Refrigeration and Air ConditioningStudy refrigeration and air conditioning for your HVAC exam. Covers the refrigeration cycle, superheat, subcooling, metering devices, and heat pump operation.
- Heating SystemsStudy heating systems for your HVAC exam. Covers gas furnace operation, heat exchanger safety, combustion analysis, venting categories, and hydronic heating.
Worked examples
Practice walkthrough
A water heating loop is modeled by heat rate in Btu/h = 500 × flow in GPM × temperature difference in °F. The loop transfers 75,000 Btu/h with a 15°F water temperature difference. What flow does this model require?
Answer: 10 GPM
Solve for flow: 75,000 / (500 × 15) = 10 GPM. The water temperature difference, not the absolute supply temperature, belongs in the formula. The constant and fluid assumptions are supplied for this exercise; a different fluid mixture could require a different model.

Practice walkthrough
A cooling unit is rated at 42,000 Btu/h. Using 12,000 Btu/h per ton of refrigeration, what is its nominal cooling capacity?
Answer: 3.5 tons
Divide the cooling rate by the supplied conversion: 42,000 / 12,000 = 3.5 tons. A refrigeration ton is a unit of cooling rate in this problem, not the physical weight of the equipment. Multiplication would convert in the wrong direction.

All 20 practice variants
- Practice variant 1
- Practice variant 2
- Practice variant 3
- Practice variant 4
- Practice variant 5
- Practice variant 6
- Practice variant 7
- Practice variant 8
- Practice variant 9
- Practice variant 10
- Practice variant 11
- Practice variant 12
- Practice variant 13
- Practice variant 14
- Practice variant 15
- Practice variant 16
- Practice variant 17
- Practice variant 18
- Practice variant 19
- Practice variant 20
Focus Areas
Study Topics
EC EPA 608 Certification
Study EPA 608 for your HVAC exam. Covers Core, Type I, II, and III requirements, refrigerant regulations, recovery procedures, and common exam mistakes.
Study this topicRC Refrigeration and Air Conditioning
Study refrigeration and air conditioning for your HVAC exam. Covers the refrigeration cycle, superheat, subcooling, metering devices, and heat pump operation.
Study this topicHS Heating Systems
Study heating systems for your HVAC exam. Covers gas furnace operation, heat exchanger safety, combustion analysis, venting categories, and hydronic heating.
Study this topic
Keep Exploring
Related Pages
Frequently asked questions
Are these questions unique to Delaware?
No. The state directory links to a shared foundational question bank. The same practice number uses the same questions across states.
Does this page prove an exam or license is required?
No. A preparation page does not establish a licensing requirement, test availability, or eligibility. Check the official authority for your intended credential and location.
How many practice variants are available?
There are 20 variants, each with 25 questions and explanations. The variants have different sets; some questions recur between variants in new exam banks.
Can I use the practice score as an official result?
No. Practice percentages are learning feedback and are not comparable to official scaled, adaptive, or credentialing scores.