HVAC Load Calculations Flashcards
6 cards from real HVAC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 HVAC Load Calculations flashcards as text
What does Manual S (ACCA) provide for HVAC technicians and designers?
Answer: Residential equipment selection based on Manual J loads
ACCA Manual S guides technicians in selecting properly sized heating and cooling equipment that matches the Manual J calculated loads within acceptable tolerance ranges.
Which of the following is an 'internal gain' source that adds to the cooling load in a building?
Answer: Occupants, lighting, and appliances
Internal gains from people, lights, and equipment add sensible and latent heat directly to the conditioned space, increasing the required cooling capacity.
Solar heat gain through windows is accounted for in a cooling load calculation using which factor?
Answer: Solar Heat Gain Coefficient (SHGC)
The Solar Heat Gain Coefficient (SHGC) represents the fraction of solar radiation admitted through a window, used with peak solar intensity and window area to calculate solar load.
In load calculations, 'infiltration' refers to:
Answer: Uncontrolled air leakage into the building through gaps and cracks
Infiltration is the unintended entry of outdoor air through envelope leaks, adding both sensible and latent load that must be included in Manual J calculations.
What is the result of significantly oversizing an air conditioner based on load calculations?
Answer: Short cycling, poor humidity control, and increased wear
An oversized AC short-cycles (starts and stops frequently), never runs long enough to remove adequate moisture, causing high humidity, comfort complaints, and premature wear.
Which ACCA manual is used for sizing and designing residential duct systems?
Answer: Manual D
ACCA Manual D provides the methodology for designing residential duct systems, including trunk-and-branch and radial layouts, to deliver the required airflow to each room.