EPA 608 Type II - Questions and Answers R-410A requires recovery tanks rated for at least: ______. a) 240 psig b) 300 psig c) 400 psig d) 500 psig A
... [Show More] routine maintenance task which must be performed on refrigerant recycling machines is to: __________. a) check compressor seals b) change electrical fuses c) replace moisture sight glass d) change filter and compressor oil (if any) Pressure relief valve must not be: ______. a) installed in series b) installed in parallel c) installed vertically d) installed horizontally When servicing an operating unit that has a receiver/storage tank, the: _________. a) compressor should be isolated off b) liquid should be recovered last c) refrigerant should be recovered into the receiver d) gauge pressure should be achieved by venting During the evacuation of the system that contains large amounts of moisture it may be necessary to increase pressure in the system with ______, to counteract the freezing of the moisture. a) hydrogen b) oxygen c) air d) nitrogen Manifold gauge set hoses should have self-sealing connectors or hand valves to: _________. a) minimize the chance of an explosion during use b) prevent venting during recycling c) prevent a vapor lock during rapid liquid transfer d) minimize the release of refrigerant when the hoses are connected and disconnected On a high-pressure system ________ is an indicator of a possible leak. a) high head pressure b) low water temperature c) excessive superheat d) frequent purging Never use oxygen or compressed air to leak-check hardware because R-410A can: _________. a) explode when mixed with air or oxygen b) fractionate when mixed with oxygen c) condense when exposed to oxygen d) none of the above Before transferring refrigerant to an empty cylinder: _____________. a) the refrigerant should be chilled b) the refrigerant should be mixed c) the cylinder should be heated d) the cylinder should be evacuated to avoid mixing air with the recovered refrigerant After installation of a field-piped R-410A split heat pump, the unit should first be: a) evacuated b) pressurized with R-22 then leak checked c) pressurized with R-410A then leak checked d) pressurized with nitrogen then leak checked The evaporation temperature of R-134A at 0 psig is: ____. a) -21 degrees F b) -15 degrees F c) - 5 degrees F d) -1 degree F On refrigeration units that use an open compressor, the: _________ is most likely to leak if the unit is not used for several months. a) suction service valve b) rotating shaft seal c) oil drain plug d) discharge service valve Use _________ to remove ice from a sight glass. a) an alcohol spray b) water c) R-11 refrigerant d) a screw driver or flat file The EPA regulations require that leaking commercial or industrial process refrigeration equipment must be repaired when the leak rate exceeds _____ of the charge per year. a) 5% b) 15% c) 25% d) 35% To change the compressor on a system containing 40 pounds R-500, using a recycling machine that was manufactured AFTER November 15, 1993, you must isolate the compressor then: ______________. a) Simply remove the compressor b) evacuate the isolated section of the system to atmospheric pressure, then remove the compressor c) evacuate the isolated section of the system to 10 inches of vacuum and hold. If system pressure does not rise, remove the compressor d) evacuate the isolated section of the system to 15 inches of vacuum and hold. If system pressure does not rise, remove the compressor System-dependent recovery equipment CANNOT be used when: ___________. a) the appliance is leaking b) the compressor of the appliance is operational c) the ambient temperature is over 115 degrees F d) the appliance contains over 15 pounds of refrigerant While R-410A is a high-pressure refrigerant, it can be stored in the back of your service van as long as: ____________. a) the temperature inside the vehicle does not exceed 125 degrees F. This is the same guidance given for R-22 and other common refrigerants b) the temperature inside the vehicle does not exceed 125 degrees F, but R-22 can be stored in vehicles with temperatures exceeding 125 degrees F c) the temperature inside the vehicle does not exceed 1555 degrees F. This is the same guidance given for R-22 and other common refrigerants [Show Less]