Environmental Code of Practice for Elimination of Fluorocarbon Emissions from Refrigeration and Air Conditioning Systems
- Commercial /Industrial Systems (sections 2.1 to 2.6)
- Commercial /Industrial Systems (sections 2.7 to 2.13)
- Residential Systems and Domestic Appliances
- Mobile Air Conditioners (Automobiles)
- Mobile Refrigeration
- Heavy Duty Mobile Air Conditioning Systems
- Strategic Planning
- List of Recognized Industry Standards
- Examples of Labels
Commercial /Industrial Systems
2.7 Installation and Servicing
2.8 Conversion of Systems to an Alternate Refrigerant
2.9 Recovery, Reuse, and Disposal of Refrigerants
2.10 Handling and Storage of Refrigerants
2.12 Disposal of Equipment
2.13 Environmental Awareness Training
2.7 Installation and Servicing
Installation and servicing is the single largest source of ODS emissions. Principle causes are:
- improper leak testing of new installations;
- venting during installation and servicing;
- failure to repair leaks before recharging; and
- inadequate design and/or improper installation.
2.7.1 Installation of Equipment
Recommendations on the design of pipework and on the methods of connection can be found in Section 2.1. All facets of the B52-1995 Mechanical Refrigeration Code (as amended/updated from time to time) should be followed and any other applicable codes, dealing with design of mechanical rooms and ventilation requirements and space monitoring, adhered to during the siting and installation of the major components. Special attention should be paid to access for recovery and recycling.
Visual Inspections. Before installation all pipework and fittings should be thoroughly examined both for cleanliness and to ensure that they meet approved standards.
Metal Filings. No metal filings are to be left inside the cut pipework since these can cause damage to shaft seals, compressor bearings, and other internal components of compressors, leading to serious leaking and emission.
Flared Tube Connections. Compression type fittings should be used in preference to flared fittings. A suitable lubricant should be used between the back of the flare and the nut to avoid tearing the flare and allowing the flare nut to be tightened more securely. Ensure the correct grade of copper tubing is being used for the pressure and bending requirements of the installation. This will help prevent future leaks.
Flanged Connections. Only the correct type and grade of gasket material compatible for use with CFCs, HCFCs, HFCs and/or other refrigerant products and their lubricants should be used. Flanges should be tightened evenly to avoid leaks.
Nitrogen Welding Blanket. Before welding or brazing pipe joints, dry nitrogen should be allowed to bleed continuously through the system to eliminate oxidation. All mechanical joints should be visually inspected and double checked for tightness before a nitrogen pressure test is performed.
2.7.2 General Items
Refrigerants should not be vented into the atmosphere or used in place of compressed air for any purpose. Valve stem gland caps that cover gauge points and service valve caps must always be replaced and thoroughly leak tested after service. Gland packing nuts should not be tightened unless they are leaking.
Shortage of Refrigerant. A leak test should always be done upon finding a system which appears to be short of refrigerant. Some commons points where leaks appear are:
™B7 flare joints;
- brazed joints;
- compressor gaskets;
- control bellows;
- shaft seals; and
- where there are traces of oil.
The low pressure side of a system should be given a positive pressure before leak testing the evaporator, heat exchanger, thermostatic expansion valve, or solenoid valve. This can be achieved by reversing the cycle if the system is of the hot gas type.
In a normal application, high and low sides of the unit equalize on shut down. The static pressure is more than enough to locate leaks.
On sub-atmospheric applications, the evaporator water temperature can be raised a few degrees to facilitate leak testing, taking care not to exceed pressure of the relief devices.
Belt Drives. The belts on open belt driven compressors should be thoroughly checked for wear, damage, and tension. Worn or damaged belts, misalignment, or over-tensioning can cause compressor shaft seal and front end bearing failure, resulting in leaks.
Component Isolation. When a leak has been located, that part of the system must be isolated and pumped down, using recovery/recycling equipment. If isolation is not possible, the charge should be pumped back into the system receiver or into a suitable approved storage container(s).
Purging Manifold Gauge Sets. Hoses with back check or isolation refrigerant valves located within 15 to 30 cm (6 to 12") from their end should be used to minimize emissions. Purge gas must be collected using appropriate technologies. Non-condensables such as air from the lines can be recovered using conventional or adsorption technology.
2.7.3 Cleaning and Flushing
Contaminated systems require cleaning and flushing after a hermetic or semihermetic compressor failure or motor burn out:
- cleaning or flushing fluid should be contained within the confines of the system; and
- procedure must include:
- - recovery of refrigerant,
- - circulation of flushing fluid,
- - recovery of flushing fluid,
- - installation of a new compressor,
- - new suction line filter drier,
- - a leak test, and
- - evacuation and dehydration of the system.
New, recovered, recycled, or reclaimed refrigerant is then charged back into the system for circulation and final cleanup to remove trace contaminants.
Cleaning and Flushing of Large Systems. On large systems, isolate as many sections of the system as possible. Remove contaminated refrigerant to approved recovery containers. Clean each section separately, or when the system is empty, the component parts should be removed, capped off and taken off site for cleaning. The cleaning should be carried out using a non- ODS as a cleaning agent.
Passive Recovery. Passive recovery on small systems using the unit compressor and a bucket of ice is no longer an acceptable practice.
Recovery Equipment Standard. All recovery equipment should, as a minimum, meet the ARI 740-93 standard or other standards or guidelines recommended by federal/provincial agencies as amended or updated from time to time, for extraction efficiency (see Appendix A).
System Dehydration. After the cleaning operation is complete, the major component parts should be reassembled into the system with the new compressor. The system should be drawn into a deep evacuation of 500 µm of Hg or less and the discharge from the vacuum pump recovered using the best available technologies.
2.7.4 Service Records
An up-to-date service record should be kept close to the equipment or with the owner and should be made available for inspection by the proper authorities. This should include details on leak testing and quantities charged or recovered.
2.8 Conversion of Systems to an Alternate Refrigerant
2.8.1 Alternate Refrigerant
System or equipment conversion to a refrigerant with a significantly lower, or zero ODP is one of the best ways to reduce ODS emissions. It is cheaper than equipment replacement. Ultimately all CFC equipment will have to be converted or replaced.
Owners of a large number of systems should develop a long-term strategic plan. This applies to both high pressure and low pressure equipment. Selection of suitable alternative refrigerant should be made by a qualified person. Consult refrigerant manufacturers and/or a consulting engineer.
Alternative refrigerants should be examined for effect on efficiency and capacity as well as effect on motor windings, gaskets, and seals. In addition, for flammable refrigerants or blends, check the Canadian Electrical Code, the B-52 code, CSA, and building code. Highly flammable refrigerants may require systems to be re-wired to meet explosion proof requirements.
2.8.2 Selection of Equipment
Generally, equipment for conversion should be less than 20 years old to avoid early replacement cost.
The equipment and system should first have a thorough leak test and all leaks repaired. A performance test or check should be done on the equipment. A review of the energy efficiency of old versus new may be part of the equation.
2.8.3 Prevention of Emissions and Leaks by Preplanning
Leaks can be prevented by ensuring that the system will be tight after conversion. Existing seals and gaskets should be checked to be sure they are compatible with the new refrigerant and refrigerant oil. If the system is hermetic, motor winding compatibility should also be verified. Any other plastic or elastomeric parts, such as tubing, should be checked for compatibility. The type of oil to be used should be verified so that proper system cleaning can be done before conversion.
Prevention of Emissions and Leaks During Conversion. To prevent leaks during conversion, qualified service persons with experience in equipment conversion should be used. After the system has been shut down and is at room temperature, recover all refrigerant and put it in approved recovery containers. Use approved recovery equipment. Oil in the crankcase should be heated to vaporize residual refrigerant which should be recovered. For low pressure systems the evaporator temperature can be raised using hot water.
Evacuate the system to <75 µm of Hg by using a vacuum pump and pass the discharge through a resin adsorption system. If necessary, flush the system in accordance with the refrigerant and equipment manufacturers' recommendations.
Dismantle the system and change any gaskets or seals, etc. as necessary. This is best done one section at a time.
It is usually best to replace any removed gaskets with new ones which are compatible with the new alternative refrigerant and oil to prevent leaks.
Install recovery connections and valves where required (one per section) and then do a second low vacuum leak check. If the system is leaking, check all joints, valves, and connections and tighten as required, until the unit is leak free.
Slowly add refrigerant, to pressurize the system, one section at a time. Leak check each section with an electronic leak detector before proceeding to the next. If there is a leak in any section recover all the refrigerant and repair the leak before proceeding.
Once the system has been fully charged with the correct amount of refrigerant and oil, run the system for the recommended time and do another leak check. The weight of the old refrigerant recovered should be logged.
The used refrigerant should be retained for other systems or returned to the supplier for a credit, (see Section 2.9). Re-label the system to indicate the amount and type of both new refrigerant and oil. Recheck for leaks after 24 to 48 hours operating time.
2.8.4 Equipment Replacement
Equipment replacement is available when the previous CFC equipment is no longer serviceable or has outlived its useful life. Suitable long-term alternative replacement refrigerants would be the logical choice for the new equipment.
2.9 Recovery, Reuse, and Disposal of Refrigerants
Venting of any refrigerant, other than water, to the atmosphere during manufacturing, installation, operating or servicing should be prevented by practicing due diligence and the recovery, recycling and reuse of refrigerant. Owners are responsible for the maintenance, operation, and security of their equipment - as well as ensuring operators are adequately trained.
2.9.2 Performance Testing
When refrigerant is used in performance testing of units or systems in both development and production operations only Transport Canada approved recovery cylinders can be used to capture refrigerant that would otherwise escape to the atmosphere.
2.9.3 Installation and Servicing
Manufacturers may use auxiliary receivers or specially approved "ton tanks" to recover larger quantities of refrigerant from refrigeration and air conditioning equipment to facilitate the reuse of the refrigerant charge following servicing.
Small Self-contained Systems. In smaller capacity equipment it is not usual to fit receivers and provide pump-down capability. In such cases only approved recovery cylinders, or approved refrigerant drums for low pressure refrigerants, may be used for the temporary storage of recovered refrigerants.
Cylinder Hazards. Hazards may arise as there are safety issues in the use of refrigerant containers as storage vessels. A refrigerant container is a pressure vessel if its capacity is greater than 28.32 L (1 ft3).
All approved containers should be designed to meet the Canadian Transport Commission (CTC) specifications. The design maximum working pressure should not be exceeded in any filling operation, however temporary. An approved container should not be filled to more than 80% of its normal refrigerant capacity, when used for recovered refrigerant.
Cylinder Specifications Under the Transportation of Dangerous Goods Act
(TDGA). All cylinders must meet the appropriate specifications listed in the Transportation of Dangerous Goods Act. All cylinders should be properly labelled as to content and weight, as required under TDGA with the appropriate Workplace and Health Material Information System (WHMIS) language and labelling. The design specifications and pressure rating should be stamped on the cylinder.
Refrigerant/Oil Mixtures. Refrigerant/oil mixtures have a lower density than refrigerant alone, and so, the weight carrying capacity of refrigerant containers will be reduced for refrigerant/oil mixtures compared to pure refrigerants.
Filling Approved Recovery Cylinders. Never store cylinders near any source of heat or where temperatures could exceed 51.7°C (125°F). Approved cylinders should only be filled to 80% of their fill capacity by weight for normal ambient temperatures of around 21°C (70°F) and should not be filled beyond 60% if the temperatures could reach 48.9°C (120°F).
Corrosion may occur if contaminated refrigerant is decanted into a refrigerant container.
Container Belonging to a Third Party. If a refrigerant container belonging to a third party (e.g., a refrigerant manufacturer), is to be used as a temporary receiver, written permission of the owner of the container must be obtained in advance.
Recovery Cylinders. Recovery cylinders (have a broad yellow band and ASHRAE designated colour) must be inspected and hydrostatically retested every five years by the owner. Virgin cylinders usually only have a one-way valve and cannot be used to store recovered refrigerant, because they should not be contaminated.
2.9.4 Recovered Refrigerant, Reuse, and Disposal
Refrigerant removed from working equipment must be recovered, reused, and recycled by the service person or sent to the supplier for reclaim or disposal. Alternatively, it may be sent to an independent reclaimer or to a licensed disposal facility.
A recovery unit does not bring refrigerant to a new level of purity. The refrigerant should only be returned to the same refrigerant system or a similar system of the same owner. If the refrigerant is to be used elsewhere, only recycling equipment meeting the ARI 740-93 and ARI 700 standard, latest edition or other standards or guidelines recommended by federal/provincial agencies is acceptable to ensure that Original Equipment Manufacturer (OEM) equipment warranties within the industry are valid (see Appendix A).
A service person or equipment owner/operator who recycles a refrigerant using his/her own equipment should ensure that the equipment is intended for the type of refrigerant being processed, and that it will clean the refrigerant to meet the industry recognized standards. Recycling machines must meet the ARI 740-93 and ARI 700, latest edition, Purity Standard or other standards or guidelines recommended by federal/provincial agencies if OEM equipment warranties are to be valid.
An external agency that recycles or reclaims used refrigerants should ensure that the equipment it uses is functioning properly and the recycled or reclaimed refrigerant meets at least the recognized industry standards (ARI 700; should be verified by laboratory analysis) (see Appendix A). If facilities are available, refrigerant that cannot be reused should be returned to the refrigerant manufacturer to be destroyed or reclaimed by an approved facility.
2.10 Handling and Storage of Refrigerants
Refrigerant can be lost to the atmosphere during the handling and storage of refrigerant containers. Some sources of emissions are faulty valves, pin-hole leaks, and improper closing of bungs and valves on drums.
Refrigerant Storage. Refrigerant containers should be stored in a cool dry place, away from risk of fire, and sources of direct heat. Areas where large quantities of refrigerant containers are stored should be monitored.
Refillable Refrigerant Containers. Effective the date of publication of this document, only refillable refrigerant containers should be filled in Canada or imported into Canada by those who are registered to import refrigerants under the Canadian Environmental Protection Act (CEPA).
Pressure Testing of Hoses and Equipment. Hoses and gauges should be pressure tested to prevent refrigerant emissions to the atmosphere. Dry nitrogen should be used to pressure test the hoses and gauge manifold for leaks at regular intervals before they are attached to a system.
Charging Lines. Charging lines should be as short as possible and fitted with either back check valves or an isolation valve within 15 to 30 cm (6 to 12") of the end of the charging lines.
Refrigerant Transferred. Refrigerant transferred to a sealed system should be metered by either weight or volume using approved weigh scales or a volumetric charging device. The use of quick disconnect fittings having one-way valves is strongly recommended.
Charging Cylinders. Charging cylinders may be used to charge or recharge air conditioning or refrigeration systems and should not be used as storage vessels to transport new, used, recycled, or reclaimed refrigerant from the shop to the job site.
Refrigerant Container Handling. Containers should be handled carefully and not dropped to prevent mechanical damage to the container and its valve. When not in use, container valves should be closed, and the valve outlet cover nut or cap screwed on.
Refrigerant containers should not be manifolded together if there is a possibility of temperature differences existing between them, since this will result in refrigerant transfer and the danger of overfilling the coldest container. Where containers are manifolded together, care should be taken that all containers are the same height to avoid gravity transfer between containers. These items constitute safety hazards as well as sources of leaks.
Refrigerant Transfer Between Containers. Refrigerant should be carried out in a way that is safe and will prevent any chances of release or over-filling when refrigerant is transferred from one container to another.
A pump and weight scale should always be used. Establish a pressure differential between the containers using a pump or by heating of discharging container under controlled conditions. Heating of the discharge container must be of an indirect method (warm water or forced warm air) to a maximum 49°C (120°F). Under no circumstances should direct heating of any type be used, with the exception of plug-in charging cylinders (dial-a-charge).
The maximum carrying capacity, when filling refrigerant containers, is a function of the internal volume of the container and the liquid density of the refrigerant at a reference temperature.
Service personnel removing refrigerant for recovery have no practical way of determining the density of a given refrigerant charge. (Under ideal room conditions (21°C or 72°F).) A good rule of thumb is to not exceed 80% of the maximum net weight capacity as stamped on the upper portion of the cylinder. The receiving container should be on a portable scale to ensure over-filling does not occur.
Up-to-date records should be kept detailing the transfer refrigerants by type and quantity, between various containers and refrigeration systems.
Accurate records of the contents of refrigerant storage containers (type, quantity, transfer in, transfer out) should also be kept. Be sure cylinders are properly labelled as to the content and weight.
It is prudent to practice due diligence by keeping proper records and getting the best information available in handling refrigerants. Some provinces require that annual records be maintained and consumptions reported. Some provinces also require that emissions or spills over a certain weight, usually 10 kg (22 lb) be reported to the local authorities.
Recommendation: It is recommended that annual consumption records of all refrigerants [including spillage of 10 kg (22 lb) or more] be maintained for a minimum of three years. Corrective actions taken as a result of spills should be documented. All releases or spills of 10 kg (22 lb) or more should be reported to the authority having jurisdiction.
2.12 Disposal of Equipment
As soon as the decision to retire equipment containing a refrigerant has been taken, the owner should arrange for full pump down of both refrigerant and oil. The equipment should then be labelled as containing no refrigerant, by a certified service technician.
Decommissioning of working equipment or mothballing of equipment that may be required for future use should include:
- removal of all refrigerant into approved recovery approved containers for retention, or returned to the supplier or manufacturer for reclaiming;
- charging of the closed loop with dry nitrogen to help prevent contamination of the system; and
- inspection of the equipment at regular intervals to ensure that adequate pressures are maintained, to prevent contamination.
2.12.2 Decommissioning of Smaller Equipment
Equipment or systems should be properly labelled to indicate they are empty. In some provinces, a 5-cm green or yellow label is attached to decommissioned equipment with the service person's certification number on it. This policy should be adopted across Canada by January 1, 1997.
Smaller air conditioning and refrigeration equipment should be stored inside heated building, be certified leak free and inspected annually by a properly trained, certified person. The equipment owner should have the refrigerant removed and stored in approved cylinders if the owner intends to keep the unit in a decommissioned state for more than four months.
2.12.3 Receiver Condenser
The refrigerant charge on larger equipment should be pumped down and isolated in the receiver or receiver condenser storage, providing valves are holding and there is a pressure relief device to protect the vessel in accordance with the appropriate code requirements.
2.12.4 Equipment Disposal
Refrigerant and oil must be recovered from equipment before disposal. The owner or a representative should be able to show proof that the guideline or provincial regulation has been satisfied by presenting a copy of the completed work order to the metal shredder or the land fill operator before the equipment is removed for disposal . Appendix B shows a sample of a label that can be used to identify equipment that is refrigerant free. Oil must also be recovered and properly disposed of.
Building Demolition. The owner (or representative) of a building containing equipment which used refrigerants for its operation should show proof that the appropriate guideline or provincial regulation has been followed before demolition. In some cases, the local "permit for destruction" or demolition may already ask if the building contains refrigeration or air conditioning equipment. Only those persons who have been properly trained in the safe handling of refrigerants may recover the refrigerant. Residual oil must also be recovered for disposal or recycling.
2.13 Environmental Awareness Training
Environment Canada, provincial, and territorial authorities have recognized two environmental awareness training courses. The Environment Canada course was developed to provide consistent understanding of the environmental issues of ozone depletion and pollution prevention as it pertains to the Air Conditioning and Refrigeration Industry.
2.13.1 Training of Individuals Handling CFCs, HCFCs and HFCs
There is a general need for continuing the delivery of environmental awareness training programs. To provide consistent training nationally, large companies, trade associations, labour organizations, community colleges, and other provincially recognized learning institutions across Canada have developed curricula which include environmental awareness training programs.
2.13.2 Environmental Awareness Card and Certification
The Provincial Ministers of Labour and Ministers of Education are responsible for TRADE QUALIFICATIONS. The Ministers of the Environment are concerned about pollution prevention and refrigerant emissions to the atmosphere.
The Environmental Awareness Card is issued on behalf of Provincial Ministers of the Environment to all service persons who have taken an environmental awareness course in accordance with the applicable provincial regulations. This card should be carried at all times and is required in order to purchase refrigerant in most provinces.
The Environmental Awareness card is not a Trade Qualification Certificate (or permit) and does not allow those persons, not permitted by other regulations, to work in the refrigeration or air conditioning trade.
2.13.3 Standardized Training of (Apprentice) Service and Repair Persons
A number of provinces have adopted the environmental awareness training program as a course component of their provincial trade school training programs.
- Date Modified: