EPA 608 CORE PRACTICE TEST WITH 100% CORRECT ANSWERS

All Refrigerant Oils are Hygroscopic: False A violation of the Clean Air Act, including improper record keeping, is subject to a penalty of a fine of up to _____ per day per violation: $44,539 per day Lifetime of CFCs is believed to be in the range ______ : 20 to 100 years CFCs are highly stable in lower atmosphere and have a lifetime of about 20 to 100 years. This higher lifetime helps in diffusing CFCs into stratosphere where CFC molecule react with UV radiation depleting ozone layer. During each vacuum decay test, it is observed that after creating the vacuum, the pressure of the system increases to greater than 0 psig and stops at some point, Then: The refrigerant could be trapped in the system. If system has leak, the pressure increases to 0 psig (atmospheric pressure) and stops. If the pressure is greater than 0 psig and stops at some point means refrigerant or water is still evaporating in the system. If your recovery unit does not have a sub-cooling feature recovery rate will be Slower. Recovery unit with sub-cooling feature accelerates the rate of recovery as it lowers the temperature of the recovery tank A recovery cylinder can maximum store _____ number of refrigerants: One. In recovery cylinder refrigerants shall not be mixed. Only _____ refrigerant can be transferred or sold to another individual Reclaimed. Reclaimed refrigerant shall meet ARI 700 purity standard A vacuum test could actually hide a leak: True. Vacuum test is not the efficient of leak detection. Halons were completely phased out by 1994. One chlorine atom in stratosphere can able to destroy approximately _______ number of ozone molecules: 100,000 In stratosphere, when sun’s UV radiation breaks down the CFC molecule chlorine ion is formed. This chlorine ion strips an oxygen atom from ozone (O3) forming chlorine monoxide (ClO) and molecular oxygen (O2). The formed chlorine monoxide (ClO) radical strips another free oxygen atom and releases the chlorine ion to repeat the process. This process continuous in cycle resulting in greater depletion of ozone layer. Recovered refrigerant is stored in which of the following painted tank: Gray with yellow top. Refrigerant cannot be called reclaimed unless it meets the ______ purity standard: ARI-700 EPA has divided refrigerated appliances into _____ groups Five. Small appliances (Type I) Low pressure appliances (Type III) Medium Pressure appliances (Type II) High pressure appliance (Type II) Very high pressure appliances (Type II) It is to be ensured that the refrigerant recovery cylinder is not filled to more than _____ of its capacity 80 percent If it is filled beyond 80% during increase in temperature the refrigerant expands results in increase in pressure inside the cylinder which can lead to bursting of cylinder Which of the following is not most effective way to detect the general area of a small leaks: fluorescent Indicator Electronic leak detector can able to detect the leak rates of about 0.5 oz per year. Ultra sound leak detector listens to the noise of gas leakage.Fluorescent leak detector detects the leak with the help of dyes. These dyes can cause strains on the equipment and foreign substances in dyes could invalidate the warranty. Also this method cannot be able to detect the immediate leak. After recovering refrigerant from a sealed system, which of the following gas is used to pressurize (for leak checking) or blow debris out of the system: Nitrogen gas Nitrogen is colorless, odourless, non inflammable and readily available (economical) gas. It may not cause any acidic formation when reacts with oxygen or moisture which can result in corrosion. CO2 in presence of moisture forms carbonic acid. At which of the following stage in refrigeration cycle does the refrigerant changes from high-pressure vapor to a high-pressure liquid: Condenser As heat is removed from the refrigerant at condenser, it reaches its saturation temperature and starts to flash (change its state) into high pressure liquid Which one of the following has highest Ozone Depletion Potential (ODP): CFC CFCs has highest Ozone Depletion Potential because of the presence of chlorine element which reacts with ozone at stratosphere. The ____connects the evaporator to the compressor in a refrigerant system: Suction line Suction line brings low pressure vapor from evaporator to compressor TXV valve maintaining the pressure difference between _____ and _____ of the system Condenser,evaporator. Thermostatic Expansion Valve connected between condenser and evaporator helps in regulating the flow of liquid refrigerant entering the evaporator for variation in the load. It helps in maintain the predetermined constant evaporator superheat in refrigeration system. Which of the following substance present in refrigerant appliance results in corrosion: Acidic _____ breaks down the CFCs and frees the chlorine ion at stratosphere: Ultraviolet radiation UV radiation from sun breaks the CFC molecules at stratosphere releasing chlorine ion. This chlorine ion is responsible for depleting the ozone layer at stratosphere. Recovered refrigerant if it is clean can be returned to the same system or other systems owned by the same person without restriction: True Presence of which of the following element will reduce the stability of the ozone depletion organic refrigerant compounds: Hydrogen Chlorine and Bromine are considered as the elements responsible for the depletion of ozone layer at stratosphere. CFC compound are highly stable at lower atmosphere and have higher lifetime. Therefore they reach stratosphere and depletes the ozone layer. Presence of Hydrogen element in organic refrigerants such as HCFCs and HFCs results in decomposition at lower atmosphere. Therefore these elements have lower lifetime and cannot pose threat to ozone depletion. Ozone is a unstable molecule at stratosphere: True Ozone at stratosphere is an unstable molecule made up of three oxygen atoms. The instability of the molecule allows the free oxygen atoms to react with hydrogen, nitrogen, chlorine and bromine. If the label identifying the refrigerant is missing, then which of the following method is used to identify the type of refrigerant: Pressure-Temperature method Saturated refrigerants have a specific pressure rating at a specific temperature. If both these parameters are measured, correct refrigerant can be determined by looking at pressure-temperature chart Recovery and recycling equipment intended for use manufactured after _____ must be certified to meet the requirements of ARI 740: Nov 15, 1993 Which of the refrigerant is used in low pressure refrigerated appliance: