Quick Reference Guide - All Critical Facts, Numbers & Dates for Certification Exam
| System Type | Refrigerant | Required Vacuum/Pressure |
|---|---|---|
| Type 1 (Small Appliances) | All types (≤5 lbs) | 0 psig OR 80% recovery |
| Type 2 High-Pressure | HCFC-22 | 10 inches Hg vacuum |
| Type 2 High-Pressure | HFCs (R-134a, R-410A) | 0 psig |
| Type 3 Low-Pressure | R-123 (Chillers) | 25 mm Hg absolute |
| Year | Event |
|---|---|
| 1987 | Montreal Protocol signed (September 16) |
| 1990 | Clean Air Act Section 608 created (November 15) |
| July 1, 1992 | Venting ban effective (knowingly venting refrigerants illegal) |
| 1995 | EPA 608 technician certification required (November 14) |
| January 1, 1996 | CFC production banned in United States |
| 2016 | Kigali Amendment adopted (HFC phasedown) |
| January 1, 2020 | R-22 (HCFC-22) production banned |
CFCs (Banned 1996):
HCFCs (R-22 banned 2020):
HFCs (Current, phasedown started):
Natural Refrigerants:
| Commercial refrigeration | 35% annual |
| Comfort cooling (≥50 lbs) | 20% annual |
| Industrial process | 35% annual |
| Repair deadline | 30 days |
| Class | Toxicity | Flammability | Examples |
|---|---|---|---|
| A1 | Low | None | R-134a, R-410A, R-22 |
| A2L | Low | Mildly flammable | R-32, R-454B, R-1234yf |
| A3 | Low | Highly flammable | R-290 (propane), R-600a (isobutane) |
| B1 | High | None | R-123 (TLV 50 ppm) |
Subcooling = Saturation Temp - Liquid Line Temp
Normal range: 10-20°F for proper charging
Superheat = Suction Line Temp - Saturation Temp
Normal: 8-12°F (TXV), 10-20°F (fixed orifice)
Annual Leak Rate % = (Amount Lost / System Capacity) × 100
Example: 20 lbs lost from 100 lb system = (20/100) × 100 = 20%
→ Comfort cooling system must be repaired within 30 days (20% threshold exceeded)
Effective date: July 1, 1992
Montreal Protocol (1987): "1987 = SEVEN years before CFC ban"
CFC Ban (1996): "1996 rhymes with NIXED"
R-22 Ban (2020): "2020 = Perfect vision = CLEARLY the end"
Venting Ban (July 1, 1992): "July = Independence from venting"
Recovery levels: "R-22 = 10 (two digits), HFCs = 0 (zero ozone)"
Leak thresholds: "20% Comfort, 35% Commercial (C-C)"
Small appliance: "FIVE pounds or less = FIVE letters in SMALL"
Type 3 recovery: "25 mm Hg = TWO-FIVE = Type TWO and Type FIVE don't exist"