Classrep2

Techs maintaining, servicing, repairing, or disposing of low pressure appliances must be certified as? - ANSWER Type III or universal technician As of what date was the sale of CFCs and HCFCs restricted to certified techs? - ANSWER Nov 14, 1994 Who is responsible to comply with changes in section 608? - ANSWER The technician Because low pressure systems operate in a vacuum , where will leaks occur? - ANSWER Gaskets or fittings (allow air or moisture into the system? What is the most ...

What type of equipment can be worked on with Type III certification? - ANSWER low pressure The most efficient method of leak checking a charged low-pressure refrigeration unit is to - ANSWER pressurize the system by the use of controlled hot water or heater blankets When pressurizing a system, do not exceed - ANSWER 10 psig After reaching the required vacuum on an appliance when servicing, moisture is indicated by - ANSWER multiple rises in pressure over a period of time with increase o...

Technicians maintaining, servicing, repairing or disposing of low-pressure appliances must be certified as - ANSWER Type III Technician or a Universal Technician. As of November 14, 1994, the sale of CFC and HCFC refrigerants is restricted to - ANSWER Certified technicians, NOTE: If EPA regulations change after the technician is certified, it will be the technician's responsibility to comply with any future changes. Because a low-pressure system operates below atmospheric pressure (in a v...

Identify the pressure corresponding to 32 degrees F for R-123: ________. a) 23 inches of Hg vacuum b) 20 inches of Hg vacuum c) 17 inches of Hg vacuum d) 11 inches of Hg vacuum - ANSWER b) 20 inches of Hg vacuum A hydrostatic tube test kit is used to: _________. a) blow all water from the tubes b) remove any water from the machine c) vent refrigerant d) determine if a tube leaks - ANSWER d) determine if a tube leaks Excessive running of a purge system on a low pressure chiller ...

The state of the refrigerant entering the metering device is: - ANSWER High pressure liquid The following components are metering devices: - ANSWER Evaporator pressure regulator, Thermostatic expansion valve The state of the refrigerant entering the compressor is: - ANSWER Low pressure vapor Before the recovery process can be initiated, a technician must know: - ANSWER The type of refrigerant in the system Checking the pressure of a recovery cylinder at a known temperature can determ...

When using recovery or recycling equipment manufactured or imported on or after Nov 15, 1993, the required level of evacuation for low pressure equipment is _____ Hg absolute: 30mm 25mm 15mm 20mm - ANSWER 25mm The EPA requires that all commercial and industrial process refrigeration systems with more than 50lb of refrigerant be repaired when the annual leak rate exceeds ______: 35% 15% 30% 25% - ANSWER 35% Open-drive compressors are typically _____ compressors centrifugal r...

what is the primary water source for a recovery unit condensing coil? - ANSWER local municipal water supply approximately how much refrigerant vapor is left in an average 350 ton R-11 chiller at 0 psig pressure once all the R-11 liquid has been removed? - ANSWER 100 lbs a rupture disc on a recovery vessel for low pressure refrigerant relieves at ____ - ANSWER 15 psig on a centrifugal system, the purge unit takes its suction from the ____ - ANSWER top of the condenser a centrifugal ch...

What do R-11 and R-123 refrigerants have in common? A. They are oxygen depleting B. They are Class I and II substances as defined by the EPA C. Both A and B D. Neither A nor B - ANSWER C. Both A and B What is the required evacuation level for recovering refrigerant from a low-pressure appliance with a recovery machine manufactured before November 15, 1993? A. 0 psig B. 4" Hg C. 10 A Hg D. 25" Hg - ANSWER D. 25" Hg How is frost best removed from a sight glass? A. reverse ...

The maximum test pressure for leak testing a low-pressure centrifugal chiller is - ANSWER 10 psig Excessive operation of a purge system means - ANSWER The system has a leak on the sub-ambient pressure side of the system For a commercial refrigeration system with a charge of 50 pounds or more refrigerant, a substantial (or threshold) week rate will be reduced to ________ after January 1, 2019. - ANSWER 20% For a comfort cooling system with a charge of 50 pounds or more of refrigerant, a ...

Where do leaks commonly occur in low pressure systems? a. Evaporator b. Condenser c. Purge unit d. Gaskets or fittings - ANSWER d. Gaskets or fittings Where do leaks commonly occur in open-drive type compressor systems? a. Evaporator b. Condenser c. Shaft seal d. Cooling tower - ANSWER c. Shaft seal Does refrigerant go out of the system in low pressure systems or does air and moisture go in? a. Refrigerant escapes through low pressure leaks. b. Air and moisture enter the refrige...

On low pressure chillers, moisture typically enters the refrigerant system through - ANSWER air leaks from areas with gaskets or fittings The maximum test pressure for leak testing a low pressure centrifugal is: - ANSWER 10 psig Leak test and repair the chiller to reduce refrigerant loss from a pruge unit on CFC-11 chiller - ANSWER ... A hydrostatic tube test kit is used to: - ANSWER determine if a tube leaks Commercial and industrial process refrigeration systems must be repaired wh...

Microbiology is the study of what? - ANSWER-My answer: Microbiology is the study of microorganisms and their biological processes at what is called the "micro" or "microscopic" level. Answer Key: Microbiology is the study of microbes (microorganisms and viruses) and their biological processes. What is the smallest biological unit of life? - ANSWER-the cell What is a macromolecule? - ANSWER-My answer: Macromolecules are large and complicated molecules that are made up of smaller mole...

True or False: A virus is considered a microorganism - ANSWER-false what is the smallest biological unit of life? - ANSWER-cell At a generalized level, all cells are comprised of what? - ANSWER-macromolecules Animalia, plantae, Fungi, and protista are all classification under what type of organism? - ANSWER-Eukarya True or false: all multicellular microorgansims classified as animalia are autotrophic - ANSWER-false Microorganisms classified as ______ obtain most of their energy by...

True or False . Although viruses may contain their genome within an enclosed space ( much like the nucleus of a cell ) , it is considered neither eukaryotic nor prokaryotic . - ANSWER-True Describe the two basic components of a virus . - ANSWER-A has virus ( 1 ) genomic material comprised of either DNA or RNA and ( 2 ) a capsid , a membrane - like protective structure that contains the genetic material , similar to the nucleus of a eukaryotic cell . True or False . Because the genome is co...

BIOD 171 Exam Study 2 Questions &Answers 100% Correct!! True or False: As movement requires energy, metabolism can be defined as a controlled set of biochemical reactions that occur in only motile organisms in order to maintain life. - ANSWER-False; Metabolism occurs in all living organisms, not just those that move. True or False: Enzymes slow down chemical reactions to conserve energy. - ANSWER-Enzyme catalyze (speed up) chemical reactions. What is the term for metal ions that assist ...

True or false: metabolism is a controlled set of biochemical reactions that occur in living organisms in order to maintain life. - ANSWER-True True or false: enzymes slow down chemical reactions to conserve energy - ANSWER-false, they speed up (catalyze) chemical reactions The term for metal ions that assist enzymes during the catalysis reaction - ANSWER-cofactors What is catabolism? - ANSWER-The process of breaking down larger molecules into useful energy sources Upon cellular injur...

True/False. A virus is classified as a microbe. - ANSWER-True True or False: The smallest biological unit of life is the molecule. - ANSWER-False What are the four main types of macromolecules found in cells? - ANSWER-Proteins, Lipids, Nucleic Acids, Carbohydrates Proteins are formed from various combinations of [answer1] of which there are [answer2] known forms. - ANSWER-1. Amino acids 2. 20 Define an essential amino acid. - ANSWER-An essential amino acid cannot be produced by the ...

A nanometer is defined as: - ANSWER-10 -9 or one-billionth of a meter True or False: A nanometer is longer than a micrometer - ANSWER-False A nanometer is 1000x smaller than a micrometer Resolution and contrast are two critical factors that influence your ability to see an object. Explain each. - ANSWER-Resolution refers to the distance between two objects at which the objects can still be seen as separate. Poor or low resolution means two or more objects may appear as one. Contrast ...

True/False. A virus is considered a microorganism. - ANSWER-False True or False: The smallest biological unit of life is the molecule. - ANSWER-False At a generalized level, all cells are comprised of what? - ANSWER-Macromolecules A student may also answer: Proteins, Lipids, Nucleic acids and Polysaccharides but they must answer with all four to be fully correct. Proteins are formed from various combinations of _______ of which there are ______ known forms. - ANSWER-1. Amino acids ...

True/False. A virus is considered a microorganism. - ANSWER-False, Viruses are not living and as such are not considered microorganisms. Viruses can, however, be classified as microbes, a more general term that includes microorganisms and viruses. What is the smallest biological unit of life? - ANSWER-A cell What are the four main types of macromolecules found in cells? - ANSWER-Proteins, Lipids, Nucleic Acids, Carbohydrates Proteins are formed from various combinations of - ANSWER-Amin...