HVAC Exam Questions With 100% Correct Answers.

What are the 4 modes for heat transfer and example? - 1) radiation: radiator 2) conduction: heated floor, pot on stove 3) convection: forced air system 4) evaporation: AC running at house and come in from the beach sweating (idk what that means ) What are different types of heating systems? - (radiant) pros: easy to zone, min distribution loss, lack of convected heat loss cons: no duct work (need for AC system), recovers slowly pros and cons of the different heating systems? - What is the main difference between furnace and a boiler? - furnace heats air boiler heats water Why would a hydronic system potentially be more efficient than a forced air distribution system? - What are the efficiency ratings for different types of heating and cooling systems? - - AC rated by SEER or EER (min SEER is 13: BTU removed out of the air) - electric resistance heat: COP1 = 3.4 BTU/watt - heating side of heat pump: HSPF (heating seasonal performance factor) HSPF = 6.8 - combustion appliance: AFUE (annual fuel = 80%-96% min efficiency What do the ratings for the heating and cooling systems refer? - What is the minimum SEER central air conditioner manufactured today? - What are the three types of heat pumps and what makes two to these more efficient designs - 1) air source 2) ground source (so efficient bc cost and temp) 3) water source (so efficient bc cost and temp) Be able to convert Coefficient of Performance to an HSPF and HSPF to a Coefficient of Performance - Be able to list eight items that determine the heating and cooling load of a building - What is the most commonly installed HVAC system in residential construction -natural gas furnace Understand what the SHGC of a window is and the U-Factor and how these effect the performance of the window - 30% of heat makes it through the glass - ufactor=conductance (inverse of R value) What does HVAC stand for? - heating ventilation and air conditioning Do houses typically have mechanical ventilation systems? - houses do have ventilation systems but typically do not (not tight enough or have enough occupants to need one) What are the two key pieces of information on a window sticker determine its efficiency - Be able to draw a sketch of the refrigeration cycle (slide 29 HVAC Intro P.P.) - What is a Heat Pump and how does it work (slide 26 HVAC Intro P.P.) - What are the two types of cooling provided by an air conditioner? - latent: sensible: Understand the relationship between the coils in a heat pump and their location during the heating and cooling season -