Blueprint Reading

Question 1

What is a central control panel ?

Answer 1

A computer that controls the function of all dampers connected to it

Question 2

What are the 2 types of controls for dampers?

Answer 2

Barometric and motorized

Question 3

What is a benefit of bypass dampers?

Answer 3

Prevent excessive noise and uncomfortable drafts.

Question 4

What is dual duct mixing ?

Answer 4

The two airstreams are mixed in the terminal and the air is discharged at a predetermined temperature through a single duct

Question 5

What is Dual Duct non mixing ?

Answer 5

Dual duct VAVs use two inlets one supplying warm air and one supplying cold air. No mixing of airstreams. Just a closing or opening of the damper depending on the thermostat setting

Question 6

What are the two types of fan powered terminal units ?

Answer 6

Constant Volume ( series flow) 
Variable Volume ( parallel flow)

Question 7

What is an Induction Terminal Unit ?

Answer 7

The induction terminal unit uses primary air supply flowing through a nozzle to induce room air flow through the heating and cooling coils

Question 8

List the 5 advantages to VAV diffusers ?

Answer 8

• Individual space control and comfort
• control of the required air volume for each zone
• ease of installation and relocation
• flexibility for future requirements
• ease of maintanence

Question 9

How does a multi zone unit control the temperature ?

Answer 9

Controls the temperature of the air that is being distributed through the duct by mixing air at the central air unit with the use of interlocked motorized dampers

Question 10

What is the range of the ductwork static pressure ?

Answer 10

1/2” w.c. - 10” w.c.

Question 11

What does STD mean ?

Answer 11

Standard ( non variable volume ) air duct construction requirements

Question 12

What does STV mean ?

Answer 12

Standard for variable volume ducts

Question 13

Beaded sleeves that join transverse round ducts must be at least the same gauge as the duct and ______

Answer 13

4” long minimum

Question 14

Round duct transverse joints that are beaded and crimped must slip into one another ______

Answer 14

1”

Question 15

What are angle rings used for ?

Answer 15

Round duct reinforcement

Question 16

What is a spigot ?

Answer 16

The part of a fitting or collar that slips into the large end of a spiral pipe

Question 17

Duct constructed for the 1” (250 pa) and 1/2” (125pa) pressure class must meet what class?

Answer 17

Seal class C

Question 18

What is the maximum permissible length of flex duct ?

Answer 18

4’

Question 19

What is the most noteworthy difference between residential and light commercial blueprints ?

Answer 19

Grid lines

Question 20

Where does the intersection of grid lines normally occur ?

Answer 20

The centre line of columns

Question 21

What are call outs most commonly used for ?

Answer 21

Grilles and Diffusers

Question 22

What are the 3 items of information on a grille calllout?

Answer 22

Type, connection and cfm

Question 23

When there are combustibles in the ceiling space where is return air ducted ?

Answer 23

To one of the ceiling grilles

Question 24

Is plastic plumbing pipe considered a combustible ?

Answer 24

Yes

Question 25

What is the purpose of external aluminum cladding on outdoor ductwork?

Answer 25

To reduce leakage, increase longevity and to minimize wear and tear