EPA 608 study material including (Core, type 1, 2 and 3)

EPA 608 study material including (Core, type 1, 2 and 3) a vacuum pump should be connected - ANS as far away from the pump as possible a high capacity vacuum pump and short, large diameter hoses will - ANS dramatically reduce emissions, pressure drop, and evacuation/dehydration time ozone contains three - ANS oxygen atoms one chlorine atom can destroy - ANS 100,000 ozone molecules CFCs do not dissolve in water and do not breakdown into other compounds that dissolve in water - ANS CFCs cannot be washed out of the lower atmosphere ODP - ANS ozone depletion potential azeotrope - ANS where the mixture behaves like a single chemical (new refrigerant) CFCs will not damage the ozone in the stratosphere - ANS ... in 1992 the united states ordered the stoppage of all CFC production and importation after - ANS December 31, 1995 according to the clean air act, no person installing, maintaining, repairing, or disposing of any appliance may knowingly vent or otherwise release into the environment and class 1 or class 2 substance after - ANS July 1, 1992 class 1 - ANS CFC class 2 - ANS HCFC it became illegal to vent substitutes for CFC and HCFC refrigerants on - ANS November 15, 1995 any device which contains and uses a class 1 or class 2 substance as a refrigerant and is used for household or commercial purpose. - ANS appliance self contained recovery equipment type - ANS Active system dependent recovery equipment type - ANS Passive only section 609 certified technicians may buy CFC-12 in containers smaller than 20 pounds - ANS ... who must ensure that all refrigerant has been recovered prior to disposal of any appliance - ANS The final person in the disposal chain (scrap metal recycler, landfill owner, ect.) the removal of refrigerant in any condition - ANS Recovery to clean refrigerant by oil separation, non-condensable removal and single or multiple passes through replaceable filter-driers to reduce moisture, acidity and particulate matter - ANS Recycling a complicated distillation process that returns recovered refrigerant to the purity of factory fresh refrigerant. - ANS Reclaiming (ARI Standard 700) under no circumstance should different refrigerants be - ANS mixed together Currently there is NOT a drop-in for CFC-12 - ANS ... oils that are hygroscopic - ANS Ester based (polyolesters) the alkylbenzene, use for some ternary blends - ANS ... as a general rule, different lubricants should never be mixed - ANS ... oxygen and oil when mixed can form an - ANS extremely explosive mixture sight glasses can be cleaned with - ANS alcohol spray before discarding a container the internal cylinder pressure should be reduced to at least - ANS 0 psig recovery cylinders must be approved by - ANS Department of Transportation (DOT) Refridgerant cylinders should never be filled above - ANS 80% capacity refridgerant cylinders should always be stored - ANS vertical or upright position with their valves at the top Service oses must be fitted with some type of low loss fitting - ANS to prevent the loss of refridgerant for small appliances, this service port typically is a straight piece of tubing that is entered using a - ANS Piercing access valve repair of leaks in small appliances is not required - ANS but should be repaired whenever possible MVAC systems are not classified as a type 1 appliance - ANS ... The EPA requires the certification of all technicians who service Type 1 air conditioning and refrigeration to comply with future changes in the law - ANS ... any regulated refrigerant released while filling a graduated charging cylinder - ANS must be recovered refrigerants should never be mixed together - ANS ... recovery cylinders must be DOT approved for use as a recovery cylinder and should be colored - ANS Gray with a Yellow top Floats, thermistor-type sensors, and weighing scales - ANS full-limit devices moisture will combine under heat with refrigerant and oil to form - ANS Hydrofluoric and hydrochloric acids as well as phosgene gas device installed at the outlet of the condenser to store the low temperature-high pressure liquid until it is needed by the evaporator. - ANS Receiver device installed in the liquid line to filter solid contaminants and remove moisture from the liquid refrigerant. - ANS Filter-drier certification of recovery machines - ANS November 15, 1993 CFC production stopped - ANS December 31, 1995 or January 1, 1996 no venting of substitute refrigerants - ANS November 1995 no more production of CFCs - ANS 2030 low side (blue) - ANS suction high side (red) - ANS discharge freezer (ideal -17°f) - ANS low temperature Cooler (ideal-35°f) - ANS medium temperature Air conditioner (ideal-75°f) - ANS High temperature causes change of state, cannot be felt, cannot be measured with a thermometer, but does not cause a change in temperature. - ANS Latent Heat Causes a change in temperature, but not cause a change of state, can be measured with a thermometer - ANS Sensible Heat only vapor can be condensed - ANS ... only liquid can be subcooled - ANS ... heat transfer through fluid flow - ANS Convection heat transfer through a substance from molecule to molecule - ANS Conduction heat transfer through heat rays - ANS Radiation refridgerant recovery is 2 pounds per ton - ANS ... bacteria sets as 43°f - ANS ... open compressor is - ANS subject to leaking at the crankshaft heat added to refrigerant vapor that causes its temperature to rise above its saturation temp - ANS Superheated refrigerant heat removed from the liquid refrigerant that causes its temperature to drop below its saturated temp - ANS Subcooling replacing or repairing the compressor, condenser, evaporator, heat exchanger or heat interchanger - ANS Major repairs appliances that have a hermetic compressor and hold 5 pounds or less (window units, domestic refrigerators, and freezer or under the counter ice maker - ANS Small appliances system-dependent recovery devices may be used on type 2 equipment but cannot be used on any appliance with more than 15 pounds of refrigerant - ANS ... all nitrogen tanks should be equipped with a regulator to lower outlet pressure - ANS ... are typically charged with liquid through the evaporator charging valve - ANS Chillers the initial refrigerant charge into an evacuated system should be in - ANS Vapor state only The rupture disc is connected at the evaporator and is typically set to open at - ANS 15 PSIG the rupture disc is piped to the outdoors for venting - ANS ... when recharging a refrigeration system with CFC-11, 16.9 in. Hg. vacuum is necessary in the shells before charging with a liquid - ANS ... under some conditions sight glasses can freeze over with ice . should this happen the sight glass can be cleaned with - ANS alcohol spray The inlet of the purge compressor is typically connected to the top of the condenser - ANS ... test used to check for tubing leaks within a chiller - ANS Hydrostatic test when leak checking with dry nitrogen, the pressure must not exceed - ANS 10 PSIG equipment is pulled down to a deep vacuum, usually 1-mm hg - ANS at the end of this check, the vacuum reading should not increase to more than 2.5 - mm hg 35% or more in commercial refrigeration or industrial process equipment with 50 pounds of charge or more must be repaired - ANS for appliances with 50 pounds of charge or more other than industrial process equipment and commercial refrigeration, an annual leak rate of 15% or more must be repaired the oil should be heated to 130°f because less refrigerant will be contained in the oil at the higher temperature - ANS ... Water-cooled condensers are cooled with water from the local water supply - ANS ... The recovery unit's high pressure cut-out should be set for - ANS 10 PSIG the system water pumps, the recovery compressor, and the recovery condenser water should be on - ANS during vapor removal Technicians must evacuate leaking components to the lowest level attainable without substantially contaminating the refrigerant - ANS this level cannot exceed 0 PSIG recovery and recycling machines are not required to recover more than one type of refrigerant - ANS ... ASHRAE standard 15 specifies the requirements and use of refrigerants sensors in equipment machine rooms - ANS ASHRAE standard 15 requires equipment rooms to have refrigerant sensors for all refrigerant safety groups the higher toxicity refrigerants are B1 refrigerants. The most commonly used in this group is HCFC 123 - ANS ... If more than one relief valve is used, they must not be installed in series. - ANS ...