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Type II — High-Pressure Systems — HVAC: EPA 608 Tech Cert practice questions

56 multiple-choice questions and 24 flashcards on Type II — High-Pressure Systems, about 19% of the HVAC: EPA 608 Tech Cert bank. Every one carries a written rationale.

Written and maintained by Nick Burton · last updated 2026-08-22 · how we write and review questions

What this chapter covers

Type II — High-Pressure Systems is one of 8 chapters in CoStudy's HVAC: EPA 608 Tech Cert bank, and it holds 56 of the bank's 300 multiple-choice questions — roughly 19% of the total. That proportion is not arbitrary: chapters follow the certifying body's published exam outline, and the number of questions in each is set by that domain's published weight, so the share of your practice time this chapter takes matches the share of the real exam it accounts for.

Studying by chapter is worth doing once you have a diagnostic score. A single overall percentage tells you whether you are close; it does not tell you which domain is dragging. Working a weak chapter in isolation, and re-testing it in isolation, is the fastest way to move a score that has stalled — and it is why the mock exams in CoStudy report by domain rather than as one number.

Free Type II — High-Pressure Systems practice questions

7 questions drawn from this chapter, with the full rationale shown — the controlling principle behind the right answer, and why each wrong option tempts and fails.

A technician is certified for Type II work. Which appliance falls squarely within that scope?

  1. A centrifugal chiller operating below atmospheric pressure
  2. A hermetically sealed dehumidifier with a small charge
  3. A vending machine with a factory charge under five pounds
  4. A supermarket refrigeration rack system using R-404A

Answer: D — A supermarket refrigeration rack system using R-404A

D) Correct — high-pressure commercial refrigeration is Type II work. A) is a low-pressure machine and requires Type III. B) and C) are both small appliances at or below the five-pound threshold and fall under Type I; applying Type II scope to them is the classic category mix-up.

Which is a Type II EPA 608 certification covered system?

  1. Refrigerator
  2. Window AC
  3. Residential central AC
  4. Large industrial chiller below atmospheric pressure

Answer: C — Residential central AC

A/B) Type I (small appliance). C) Correct — Type II = high-pressure systems including residential central AC + supermarket refrigeration. D) That's Type III (low-pressure).

When charging an R-410A residential AC, which pressure relationship is expected at typical operating conditions vs R-22?

  1. R-410A operates at lower pressure than R-22
  2. Pressures are identical
  3. R-410A operates at significantly higher pressures (often ~50-60% higher) than R-22
  4. R-410A is sub-atmospheric

Answer: C — R-410A operates at significantly higher pressures (often ~50-60% higher) than R-22

A) Reversed. C) Correct — R-410A condenses and evaporates at higher pressures, requiring high-pressure-rated hoses, recovery cylinders, and gauges. B) They are not the same. D) R-410A is high-pressure, not low.

A technician measures suction line temperature and compares it to the saturation temperature for the suction pressure. That comparison yields:

  1. Subcooling, which confirms liquid at the condenser exit
  2. The compression ratio developed across the compressor
  3. The system's total heat of rejection at the condenser
  4. Superheat, which confirms no liquid is returning to the compressor

Answer: D — Superheat, which confirms no liquid is returning to the compressor

D) Correct — superheat is measured on the low side and tells you the refrigerant has fully boiled before reaching the compressor. A) is the mirror-image measurement taken on the liquid line and is the most common mix-up on this topic. B) is a pressure ratio, not a temperature comparison. C) is a capacity calculation, not a field measurement of this kind.

Which refrigerant is a non-azeotropic (zeotropic) blend that exhibits significant temperature glide during phase change?

  1. R-22
  2. R-32
  3. R-407C
  4. R-134a

Answer: C — R-407C

A) Pure HCFC, no glide. B) Single-component HFC, negligible glide. C) Correct — R-407C is a zeotropic blend of R-32/125/134a with measurable temperature glide and must be charged as liquid. D) Single-component HFC, no glide.

For a high-pressure appliance with charge >200 lbs manufactured AFTER November 15, 1993, the EPA-required recovery evacuation level is:

  1. 10 in Hg vacuum
  2. 0 in Hg
  3. 15 in Hg vacuum
  4. 25 mm Hg absolute

Answer: A — 10 in Hg vacuum

B) Pre-1993 small appliance value. A) Correct — 10 in Hg vacuum is required for high-pressure appliances >200 lbs (post-1993). C) That value is for very high-pressure appliances of certain sizes. D) Absolute mm Hg is the deep-vacuum dehydration target, not recovery.

Hoses on a manifold gauge set used with R-410A must be:

  1. Rated for 500 psi only
  2. Rated for the higher working pressure of R-410A (typically 800 psi or higher) with appropriate fittings
  3. Made of plastic
  4. Any hose because R-410A is low-pressure

Answer: B — Rated for the higher working pressure of R-410A (typically 800 psi or higher) with appropriate fittings

A) Insufficient working pressure. B) Correct — R-410A requires high-pressure hoses (commonly 800/4000 psi burst) and proper fittings. C) Plastic alone is unsafe. D) R-410A is high-pressure.

Type II — High-Pressure Systems flashcards

3 cards from the 24 in this chapter.

Type II covers?

HIGH-pressure systems: residential central AC, supermarket refrigeration, heat pumps.

Capillary tube vs TXV?

Cap tube: fixed restriction, no modulation. TXV: modulates based on load.

What defines a high-pressure refrigerant, and name three common examples.

A refrigerant with a boiling point roughly between minus 50 and 10 degrees C that operates above atmospheric pressure throughout the system. Examples: R-22, R-410A, R-134a, R-404A and R-407C.

Practise the full chapter

These are a sample. The full Type II — High-Pressure Systems chapter runs 80 items with per-chapter progress tracking, on the web and in the iOS app.

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