Core Exam

Question 1

What kind of construction is pier and beam used for?

Answer 1

Crawl spaces and Elevated homes

Question 2

Trusses are held together by what?

Answer 2

Cleats and Gusses

Question 3

How many busses and cleats are used to hold a truss?

Answer 3

1 Gus and 2 cleats

Question 4

What kind of flame is best for brazing?

Answer 4

Neutral flame

Question 5

What kind of flame is not good for brazing

Answer 5

oxidizing and carbonizing flames

Question 6

what kind of gas is acetylene gas?

Answer 6

Flamable gas

Question 7

what does flux do?

Answer 7

stops oxidation inside and outside the tubing surface

Question 8

when should you use flux?

Answer 8

dissimilar metals. Copper to brass

Question 9

what is the proper way to make a flare

Answer 9

tighten 1/2 turn, back off 1/4 turn, tighten 3/4 turn, back off 1/4

Question 10

what kind of threads does a tap make?

Answer 10

female threads

Question 11

what kind of threads does a dye make?

Answer 11

male threads

Question 12

how do you properly care for snips

Answer 12

wipe with oiled rag

Question 13

what do you use to adjust duct strap tool (pantsuit tool)

Answer 13

the cam on the tool

Question 14

what are the two bubbles on a level for?

Answer 14

plumb (vertical) and level (horizontal)

Question 15

what is an opinion?

Answer 15

a view or judgement

Question 16

what is a fact

Answer 16

absolute truth

Question 17

what is jargon?

Answer 17

trade terminology

Question 18

3 is what percent of 5

Answer 18

3/5= .6 * 100 = 60%

Question 19

what is the volume of air (CFM) coming from a 80,000 btu furnace with 140 degree supply and 60 degree return temps?

Answer 19

CFM = BTU/(DELTA T * 1.08) = 926 CFM

Question 20

a cleaning solution mixes 4 parts water 1 part solution 4:1

how much solution is needed if you want 20 gallons

Answer 20

4+1=5, 20/5 = 4 gal

Question 21

what is the max fill percentage of a refrigerant cylinder

Answer 21

80%

Question 22

what is the max temp a refrigerant cylinder can be kept at?

Answer 22

125 degrees

Question 23

is refrigerant heavier or lighter than air?

Answer 23

heavier. it displaces oxygen

Question 24

how many cubic ft of air weighs 1 lb

Answer 24

13.33 cu ft

Question 25

what is the specific heat of air ( amount of heat energy required to raise 1 lb of air 1 degree Fahrenheit

Answer 25

.244 btus

Question 26

how much does 1 cu ft of air weigh

Answer 26

.0741 lbs

Question 27

sensiblr btu output/ 1.08 * TD = ?

Answer 27

CFM