Unit 42 Textbook notes Flashcards
The most popular method for determining the heat gain and heat loss of a residential structure is to use?
Manual J by Air Conditioning Contractors of America (ACCA)
As the TD across the wall increases the ________ ______ increases
transfer rate
What does the U value describe?
thermal conductivity
R and U values are inverse so if a material has a R value of 30 the corresponding U value will be _______
0.033
the units of U value are ?
btus/f/sqft
Net wall area is the gross wall area minus the area of all?
windows and doors
Heat transfer through window or fall formula?
Q= U-value x TD x Area
How to calculate a partially below grade wall?
sum of heat loss from the above grade portion and sum of heat loss from the below grade portion
How is heat loss calculated for slab on grade floors?
by using the running feet of exposed slab edge
Insulation for slab can be vertical or horizontal, or can be vertical insulation that turns under the slab. This type of construction element utilizes an __ -______
F value
An F-value is expressed in btus per _________ft per degree Fahrenheit of perimeter of a slab floor
running
There is no heat gain through _______ ______ walls, slabs, basement floors
below grade
One major source for heat gain on a structure is the
windows
Human bodies produce both _______ heat and ________ heat
sensible and latent
The estimated heat gain for each full time occupant of the house is about ______btuh. Which breaks down to about ____btuh sensible and _____ of latent
430 btuh
230 sensible
200 latent
