EPA 608 flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Small appliance definition

A hermetically sealed, factory-charged appliance containing 5 pounds or less of refrigerant, such as household refrigerators, freezers, room air conditioners, dehumidifiers, and vending machines.

Type I disposal recovery target

When disposing of a small appliance, recover 80 percent of the refrigerant if the compressor is not operating, or 90 percent if the compressor is operating.

System-dependent recovery equipment

Recovery equipment that relies on the appliance's own compressor, internal pressure, or an attached vacuum pump rather than its own compressor; permitted for small appliances.

Venting prohibition

Deliberately releasing refrigerant to the atmosphere is illegal for all appliances. Recovered refrigerant must be recycled, reclaimed to AHRI 700 purity, or destroyed.

Process stub

A short length of tubing on a sealed system used for evacuation and charging; it is pinch-clamped and brazed closed once service is complete.

Recycled versus reclaimed refrigerant

Recycled refrigerant is cleaned on site for reuse in the same owner's equipment; reclaimed refrigerant is reprocessed to AHRI 700 purity and may be resold.

Motor vehicle AC exclusion

Motor vehicle air conditioners are not Type I appliances; they are governed by Section 609 rules and require a separate technician certification.

Capillary tube

A fixed-restriction metering device made of small-diameter tubing, common on small appliances; it has no moving parts and cannot be adjusted.

High-pressure appliance definition

An appliance using a refrigerant that boils below 32 degrees Fahrenheit at atmospheric pressure, such as R-22, R-134a, R-410A, R-404A, or R-407C.

200-pound evacuation trigger

An appliance containing 200 pounds or more of refrigerant must be evacuated to 15 inches of mercury vacuum before being opened for service or disposal.

Ten inches mercury vacuum

The required evacuation level for high-pressure appliances under 200 pounds of charge when recovery equipment manufactured after November 15, 1993 is used.

Pre-1993 recovery equipment levels

Recovery machines built before November 15, 1993 need only pull 4 inches of mercury vacuum for CFC/HCFC systems and 0 psig for HFC-134a appliances.

Leak rate thresholds

For appliances holding 50 pounds or more, leaks above 15 percent per year in comfort cooling or 35 percent in commercial refrigeration or industrial process must be repaired within 30 days.

R-410A charging

R-410A is a near-azeotropic blend of R-32 and R-125 that must be charged as a liquid; it operates at pressures roughly 60 percent higher than R-22.

Nitrogen pressure testing

Use dry nitrogen with a pressure regulator for leak testing high-pressure systems; never use oxygen, compressed air, or an open flame.

Recovery cylinder fill limit

A recovery cylinder must never be filled beyond 80 percent of its capacity by weight, because warming liquid refrigerant risks hydrostatic rupture of the cylinder.

Three-year record retention

Technicians and equipment owners must keep records of refrigerant purchases, recovery, recycling, and disposal for at least three years.

Low-pressure appliance definition

An appliance using a refrigerant with a boiling point at or above 32 degrees Fahrenheit at atmospheric pressure, typically R-11, R-113, or R-123 in centrifugal chillers.

25 millimeters mercury absolute

Low-pressure appliances must be evacuated to 25 millimeters of mercury absolute, roughly 29.6 inches of mercury vacuum, before opening or disposal.

Chiller compressor prohibition

The compressor of a low-pressure chiller must never be used to evacuate or recover refrigerant; a certified recovery unit is required instead.

Purge unit

Equipment that removes air and other noncondensables that leak into a low-pressure chiller, which operates below atmospheric pressure during normal running.

Rupture disc

A pressure relief device fitted to low-pressure chiller shells, typically designed to burst near 15 psig to protect the vessel from overpressure.

R-123 ozone depletion potential

R-123 is an HCFC with an ozone depletion potential of about 0.02, used to replace CFC R-11, which has an ozone depletion potential of 1.0.

R-11 boiling point

R-11 boils at about 75 degrees Fahrenheit at atmospheric pressure, so it sits at a vacuum inside the chiller and reads below zero on standard gauges.

Standing vacuum test

After evacuation, the system is isolated and the vacuum observed; a rising pressure indicates a leak or moisture still boiling off.

Universal certification

A Universal certification covers Type I, Type II, and Type III appliances, allowing the technician to service any charge size or pressure class.

De minimis release

A very small quantity of refrigerant released while connecting or disconnecting hoses during a good-faith repair is not treated as illegal venting.

Refrigerant decomposition products

Refrigerant exposed to flame or a hot surface breaks down into hydrogen fluoride, hydrogen chloride, and phosgene, so the area must be ventilated and vapors not inhaled.

AHRI 700

The standard that sets purity requirements for reclaimed refrigerant, including limits on moisture, acidity, high-boiling residues, and noncondensable gases.

ODP and GWP

Ozone depletion potential compares a refrigerant's ozone damage with CFC-11, set at 1.0; global warming potential compares heat trapping with carbon dioxide, also set at 1.0.

Liquid refrigerant frostbite

Liquid refrigerant boiling on skin causes frostbite and can freeze an eye on contact; wear gloves and goggles and flush exposed skin with lukewarm water.

Mixed refrigerant cylinder

Different refrigerants must never be mixed in one recovery cylinder; a mixed cylinder cannot be reclaimed and generally has to be destroyed.