UNIT 43 REVIEW QUESTIONS ANSWER KEY GO BACK TO INDEX
43-1) How does mechanical filtration work?
43-2) What is the normal maximum air velocity across the face of a low efficiency
panel filter?
43-3) How often should a low efficiency panel filter be changed?
43-4) How often should a renewable media, pleated surface be changed?
43-5) What factors should be considered when choosing an air filter?
43-6) Describe the MERV filter rating system.
43-7) Why are the highest rated MERV filters not used in residential applications?
43-8) Why is panel filter media sometimes coated with a viscous substance?
43-9) What is a HEPA filter?
43-10) How does increasing the airflow across a filter affect its efficiency?
43-11) What is the purpose of extending the media surface area in pleated filters?
43-12) How does increased pressure drop across a filter affect system operation?
43-13) List the three types of electronic air filter units.
43-14) What is the common operating voltage range on the cells of electronic air
cleaners?
43-15) Describe the operation of ionizing plate electronic air cleaner.
43-16) What filter characteristics should be considered when selecting an air filter?
43-17) Why should a MERV rating always state the air velocity through the filter?
43-18) How can a high pressure drop across an air filter adversely affect system
performance?
43-19) What air contaminants are addressed by UV lights?
43-20) How often do UV lamps need to be replaced?