EPA 608 Type III cheat sheet

Low-pressure appliances (typically centrifugal chillers) use refrigerants with a boiling point at atmospheric pressure at or above 0 °C at 14.7 psia; common examples are CFC-11, CFC-113, HCFC-123, and HCFC-124.

Recovery equipment for low-pressure systems must be capable of pulling the appliance down to 25 mm Hg absolute (about 0.5 in Hg vacuum) for appliances manufactured before November 15, 1993, and to 25 mm Hg absolute for appliances manufactured on or after that date; the regulatory evacuation level for low-pressure appliances is 25 mm Hg absolute.

Because low-pressure refrigerants have low vapor pressure, recovery requires a compressor-driven recovery unit or a vapor-recovery approach; simple pumping of vapor with a standard high-pressure recovery machine will not work efficiently.

A water-cooled condenser or a subcooling/heat-exchanger arrangement on the recovery unit is used to condense low-pressure refrigerant vapor, since the refrigerant must be cooled below its saturation temperature at the recovery pressure.

Refrigerant recovered from a low-pressure appliance may be recycled on-site to the same appliance or another appliance owned by the same owner; reclamation is required when the refrigerant is to be sold or transferred to a different owner, or when it is contaminated beyond recycling limits.

Recycled refrigerant intended for a different owner or for sale must be reclaimed to ARI Standard 700 purity; reclamation requires a certified reclaimer and documentation of purity.

Charging a low-pressure centrifugal chiller is done as a liquid or as a vapor depending on the unit design; for CFC-11 style machines, refrigerant is typically charged as a liquid into the evaporator or as a vapor through the charging valve to avoid thermal shock and to prevent carrying over oil.

Never mix refrigerants in a recovery cylinder; cylinders must be labeled with the refrigerant type, and a low-pressure refrigerant must not be mixed with high-pressure refrigerants, as this prevents recycling or reclamation and may render the entire cylinder a hazardous waste.

Recovery cylinders must not be filled beyond 80% of their capacity by weight; use a scale and a cylinder rated for the refrigerant's pressure, and follow DOT requirements for cylinder specification and requalification.

Low-pressure chillers operate with the evaporator under vacuum, so air and moisture can be drawn into the machine through any leak; non-condensables must be purged from the condenser using a purge unit.

A purge unit removes non-condensable gases (air, nitrogen, moisture) from the condenser; excessive purge operation indicates a leak or a problem with the purge unit itself, and the purge discharge must be vented or handled according to regulations.

Chlorine-based refrigerants (CFC-11, CFC-12) are detectable with a halide torch or electronic leak detector; HCFC-123 requires an electronic detector sensitive to HCFC-123 and a colorimetric indicator tube may be used.

Moisture in a low-pressure system forms hydrochloric and hydrofluoric acids with chlorine/fluorine refrigerants, causing corrosion and oil breakdown; moisture must be kept below the manufacturer's limit (often 50 ppm or less) using filter-driers and a moisture indicator.

Oil in low-pressure centrifugal chillers is typically a light oil (ISO 32 or similar) and is miscible with the refrigerant; oil charging must be done with a pump or hand pump while the machine is at a positive pressure or using a charging device, never by opening the system to atmosphere.

When opening a low-pressure system for service, the refrigerant must first be recovered to the required vacuum level; the machine must then be isolated, and any residual refrigerant removed before breaking the vacuum with dry nitrogen.

Refrigerant hoses and gauges for low-pressure service must be compatible with the refrigerant and rated for the pressures involved; use a manifold with low-pressure gauges reading in inches of mercury vacuum and psig.

A low-pressure chiller must never be leak-tested with oxygen or compressed air; use dry nitrogen and a trace of the system refrigerant, or an electronic leak detector, and follow the manufacturer's procedure.

When adding refrigerant to a low-pressure machine, charge as a liquid or vapor per the manufacturer's instructions and verify the charge by weight, subcooling/superheat, and the sight glass or liquid level indicator.

EPA leak repair requirements apply to appliances containing 50 or more pounds of refrigerant; low-pressure chillers commonly exceed this threshold and are subject to the leak rate and repair provisions of 40 CFR Part 82, Subpart F.

The leak rate for an appliance is calculated as the pounds of refrigerant added over the past 12 months divided by the total charge, expressed as a percentage; the trigger for repair is a leak rate exceeding 15% for commercial refrigeration and 35% for comfort cooling (industrial process cooling has its own thresholds).

For appliances with a full charge of 50 or more pounds, if the leak rate exceeds the applicable threshold, the owner must repair the leak within 30 days of discovery (or 30 days after the end of the 12-month period in which the leak was discovered), with an extension of up to 30 days if parts are unavailable or the appliance is temporarily shut down.

Initial verification of a repair must be performed within 30 days after the repair is completed, and follow-up verification within 30 days after the initial verification if the appliance has a leak rate above the threshold; verification requires an electronic leak detector or other approved method.

If an appliance cannot be repaired, the owner must develop a retrofit or retirement plan within 30 days and keep it on site; a certified technician must document the plan.

Records of refrigerant added, recovered, and the leak rate calculation must be kept for at least 3 years and made available to EPA upon request; the records must include the date, the amount and type of refrigerant, and the service performed.

Owners of appliances with 50 or more pounds of refrigerant must keep records of the date and type of service, the amount of refrigerant added, and the leak rate; technicians must provide a copy of the service record to the owner.

A leak is considered repaired only when the appliance passes verification; if the same leak recurs within 12 months, the appliance is subject to the leak repair requirements again and may require retrofit or retirement.

Chronic leak problems (leaks that cannot be repaired) require the owner to retrofit or retire the appliance within the timeframes in the regulation, and to document the plan and the reasons the repair was not possible.

Before dismantling or disposing of a low-pressure appliance, the refrigerant must be recovered to the required evacuation level of 25 mm Hg absolute (about 0.5 in Hg vacuum) for low-pressure appliances.

Appliances manufactured before November 15, 1993, must be evacuated to 25 mm Hg absolute; appliances manufactured on or after November 15, 1993, must also be evacuated to 25 mm Hg absolute for low-pressure appliances, while high-pressure appliances require 0 psig or the applicable level.

Final evacuation of a low-pressure system must be verified with a vacuum gauge (micron gauge or manometer) capable of reading in the required range; a compound gauge alone is not sufficient for verification.

Recovered refrigerant from a disposed appliance must be either recycled, reclaimed, or destroyed; it may not be vented to the atmosphere.

Refrigerant removed from a low-pressure appliance during disposal must be stored in a DOT-approved recovery cylinder, labeled, and not overfilled beyond 80% of capacity.

When a low-pressure appliance is to be disposed of, the technician must provide the owner or disposal facility with documentation of refrigerant recovery, including the amount recovered and the evacuation level achieved.

Appliances that are permanently retired must have all refrigerant removed and the system opened to the atmosphere only after evacuation is complete; the service ports must then be sealed or the appliance tagged as evacuated.

Venting of refrigerant is prohibited except for de minimis releases; safe disposal requires recovery, and the technician must not rely on the appliance's own compressor to evacuate the system.

Recovery equipment used for disposal must be capable of achieving the required vacuum and must be maintained and calibrated; a recovery unit that cannot reach 25 mm Hg absolute is not acceptable for low-pressure appliance disposal.

Section 608 of the Clean Air Act prohibits venting ozone-depleting refrigerants and their substitutes; the regulation is codified at 40 CFR Part 82, Subpart F.

Technicians servicing low-pressure appliances must be certified under EPA's Section 608 program; Type III certification covers low-pressure appliances, and a Universal certification covers all appliance types.

Certification is obtained by passing a proctored exam; the Type III exam covers low-pressure appliance servicing, recovery, recycling, and reclamation, leak detection and repair, and safe disposal.

The sale of ozone-depleting refrigerants is restricted to certified technicians; refrigerant purchased must be sold to a certified person, and the seller must verify certification.

Refrigerant that is reclaimed must be processed by an EPA-certified reclaimer and must meet ARI Standard 700 purity; reclaimed refrigerant must be labeled with the reclaimer's name and the purity level.

Owners and operators of appliances with 50 or more pounds of refrigerant must keep service records, leak rate calculations, and retrofit/retirement plans for at least 3 years and make them available to EPA.

The regulation requires that refrigerant be recovered from appliances before disposal and that technicians use certified recovery equipment; venting is prohibited and subject to enforcement and penalties.

Small appliances containing less than 5 pounds of refrigerant have separate recovery requirements; low-pressure appliances generally exceed this threshold and are subject to the full appliance requirements.

EPA may require certification and recordkeeping for refrigerant substitutes under the Significant New Alternatives Policy (SNAP); technicians must follow the applicable requirements for the specific refrigerant used.