EPA 608 Study Guide

Recovery Requirements for Small Appliances

Learn the EPA recovery requirements, percentages, and vacuum levels for small appliances.

Recovery Techniques for Small Appliances

Learn the tools, access methods, and techniques used to recover refrigerant from sealed systems.

Substitute Refrigerants & Oils

Understand the refrigerants and oils used in small appliances, including retrofits and modern replacements.

Safety, Leaks & Cylinders

Cover safety precautions for flammable refrigerants, leak detection rules, and cylinder handling for small appliances.

General Service & Maintenance

Learn practical service tips for small appliances including dehydration, diagnostics, and moisture prevention.

Refrigeration Fundamentals for Small Appliances

Understand capillary tubes, hermetic compressors, and the refrigeration cycle as it applies to small appliances.

Small Appliance System Design

Understand the hermetically sealed system design, capillary tube metering, compressor types, common refrigerants, charge sizes, and access points used in small appliances.

Hydrocarbon Refrigerants in Small Appliances

Understand the properties, safety classifications, charge limits, and servicing precautions for flammable hydrocarbon refrigerants R-290 and R-600a.

Disposal & Decommissioning of Small Appliances

Learn EPA disposal requirements, the final-person-in-the-chain rule, documentation obligations, and proper decommissioning procedures for small appliances.

High-Pressure System Fundamentals

Understand high-pressure systems, common refrigerants, and key components like receivers, filter driers, and accumulators.

Superheat & Subcooling

Master superheat and subcooling calculations with worked examples, PT chart usage, and TXV operation principles.

PT Chart Diagnostics

Use pressure-temperature charts with gauge readings to diagnose non-condensables, charge problems, and heat exchanger performance.

Recovery Requirements

Learn the EPA-mandated evacuation levels for high-pressure systems based on charge size and equipment age.

Leak Detection & Repair

Understand leak rate thresholds, detection methods, and repair documentation requirements.

Leak Rate Calculations

Calculate annual leak rates, apply EPA thresholds, and understand chronic leaker determination and retrofit/retire timelines.

Recovery Techniques

Learn practical recovery methods including pump-down, liquid vs. vapor recovery, and cylinder safety.

Service Valves & Gauge Hookup

Master service valve positions, Schrader valves, gauge manifold hookup procedures, and hose purging techniques.

Oils & Moisture Contamination

Understand POE vs mineral oil properties, acid formation from moisture, compressor burnout contamination, and oil management.

Evacuation & Charging

Learn Type II evacuation levels, charging procedures for blends, weighing-in method, and nitrogen sweep before brazing.

Troubleshooting Common Failures

Diagnose restricted metering devices, dirty condensers, low/high charge, and compressor valve failures using gauge readings.

Safety Practices for High-Pressure Equipment

Learn PPE requirements, brazing safety with nitrogen purge, R-410A pressure hazards, proper refrigerant handling, and ventilation for high-pressure work.

Compressor Types & Operation

Learn reciprocating, scroll, and rotary compressor principles, failure modes, oil return, crankcase heaters, and overload protectors.

Low-Pressure Refrigerant Fundamentals

Understand what defines low-pressure refrigerants, their key properties, and why these systems operate differently from high-pressure equipment.

Centrifugal Chillers

Learn how centrifugal compressors operate, how flooded evaporators and shell-and-tube condensers work, variable-frequency drives for capacity control, and key chiller construction details.

Purge Units

Understand why purge units are essential for low-pressure chillers, how high-efficiency models minimize refrigerant loss, what excessive purge runtime indicates, and maintenance requirements.

Recovery & Recharging

Learn the required evacuation levels for low-pressure systems and proper techniques for charging refrigerant.

Recovery Techniques

Learn practical methods for recovering refrigerant from low-pressure systems efficiently and safely.

Leak Detection & Repair

Understand leak rate thresholds, testing methods, and repair requirements for low-pressure equipment.

Leak Rate Calculations

Learn how to calculate annual leak rates for centrifugal chillers, annualize partial-year data, understand comfort cooling vs. IPR thresholds, and know the AIM Act requirements for HFC systems.

Safety & Handling

Learn the safety classifications, exposure limits, and equipment room requirements for low-pressure refrigerants.

Machinery Rooms

Learn why B1 refrigerants require dedicated machinery rooms, the ASHRAE 15 requirements for ventilation and monitoring, SCBA placement rules, and emergency procedures.

Rupture Discs & Relief Devices

Learn how rupture discs and relief valves protect low-pressure chillers from over-pressurization, their differences, replacement requirements, and critical safety rules.

Evacuation & Charging Procedures

Master the critical distinction between post-1993 and pre-1993 evacuation requirements, vapor-first charging procedures, and the importance of water circulation during charging.

Chiller Maintenance & Tube Testing

Learn about eddy current testing, hydrostatic tube testing, oil analysis, and key maintenance procedures for centrifugal chiller tube bundles.