Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Level 2: Distribution Systems > Distribution Systems > Flashcards

Distribution Systems Flashcards

1
Q 
Air distribution arrangements:
1. single \_\_\_\_
2. terminal \_\_\_\_\_\_\_
3. induction \_\_\_\_\_\_
4. \_\_\_\_\_ zone
bypass \_\_\_\_\_ zone (terminal reheat)
A
  1. single zone
  2. terminal reheat
  3. induction reheat
  4. multizone
  5. bypass multi zone (terminal reheat)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Distribution arrangements can have two different types of air flow;
1.
2.

A
  1. constant volume

2. variable volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Residential is all ______ duct because it is cheaper

A

single

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Single zone distribution characteristics:

  1. responds only to one zone or ______ condition
  2. can be single or _____ fan
  3. can incorporate reheat coils for __________
  4. economizers can be used when OA is below ___
  5. constant volume or _______ volume air flow
  6. energy efficiency is ______
A
  1. space
  2. dual
  3. dehumidification
  4. 55F
  5. variable
  6. good
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

If static pressure in return is too high in return duct what happens?

A

It will be exhausted outdoors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Terminal Reheat Distribution:

  1. Modification of single zone air and ______ systems
  2. Responds to ______ zones or space conditions
  3. can be single or _____ fan
  4. incorporates a ______ coil at each zone for individual temp control
  5. Terminal box can be reheat unit (medium velocity) or _______ unit (high velocity)
A
  1. water
  2. multiple
  3. dual
  4. reheat
  5. induction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Single Duct Terminal Reheat:

  1. Primary air supplied down the duct at approx ___F
  2. the air is reheated at the zone on a call for heat at the zone ________
  3. used in large buildings with many zones with large variations in ____
  4. ____ an energy efficiency system
A
  1. 55F
  2. thermostat
  3. load
  4. NOT
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does AHU mean?

A

Air handling unit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is a system that does not have any return air called?

A

make up air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens when you block multiple diffuser outlets?

A

over pressurization in ducts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the best way to fix over pressurization?

A

variable speed motor that can adjust to whatever demand is required

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are VAV terminals? (Square/round box before diffuser outlet)

A

They talk to thermostats to adjust cooling/heating needs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

VAV terminals sometimes have an electrical _______ coil at the terminal

A

reheater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

VAV terminals control flow of air with _______ on the inlet

A

dampers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

If the thermostat tells the VAV it is too cold in the room it will _______ the damper to bring in less cool air

A

adjust

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Some reheat coils are hot ______ fed

A

hot water fed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where are economizers located?

A

outside air hood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is an enthalpy/temp sensor on an economizer?

A

tells the controller to open or close damper based on latent/sensible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Economizer:

As outdoor air damper begins to modulate open the return air damper will begin to modulate closed to ensure correct ______ air is maintained

A

mixed

20
Q

Some economizers use outdoor air as ____ cooling for the building

A

free

21
Q

Set economizer at A,B,C,D settings based on what factors

A

temperature and relative humidity

22
Q

Single Duct; Terminal Reheat Distribution:

  1. economizers can be used to save on _______ costs
    - energy efficiency is poor
  2. Induction units were designed for use in exterior rooms of multi story buildings where a high sensible loss occurs, yet at the same time cooling is required in the interior of the building
A
  1. cooling
23
Q

*Single Duct; Terminal Reheat Distribution; Induction Unit:

  1. Coils: Dual temp ______ (DTW) System
  2. Low/Med/High (LMH) __ System

Terminology:

  1. Primary air (______ from main equipment plenum)
  2. Secondary air (room induced by ________)
A
  1. water
  2. TW
  3. supply
  4. primary
24
Q

An induction box uses the Bernoulli principle to draw room air in and mix with the ______ air

A

primary

25
Q

Difference between an induction unit and VAV?

A

induction unit is a VAV but adds induced air for mixing purposes

26
Q

Single Duct; Multi-zone:

Modification of single duct system; All Air System
1. Two separate plenums; 1 for _____, 1 for ______

A
  1. heat, cool
27
Q

Single Duct; Multizone

  1. Responds to multi-zone or space conditions (normally __ or less)
  2. Hot deck temperature is determined by _______ stat
  3. Cold deck temp maintained at __F
  4. Zone air is mixed by zone mixing dampers located within ____ ________
A
  1. 12 or less
  2. outdoor stat
  3. 55F
  4. main plenum
28
Q

what are mixing boxes used for?

A

to maintain temperatures so there is not swing in room temp from furnace coming on/off

29
Q

Single Duct; Multizone

  1. ____ supply duct to each zone
  2. economizers can be used
  3. Fan arrangement is _____ through
  4. Induction unit __ normally used
  5. Constant _______
A
  1. one
  2. blow
  3. not
  4. volume
30
Q

Single Duct: Bypass Multizone; Modification of multizone;

  1. Air and Water system: Has ___ separate plenums; 1 for _____, 1 for ______ cool
  2. cold deck is maintained at ___F
A
  1. one for cool, one for bypass cool

2. 55F

31
Q

Single Duct: Bypass Multizone

  1. Responds to _____ or space temperatures
  2. Normally used in milder climates as it uses return air heated by space as ______ heat
  3. If further heating is required the system is equipped with _______ ______ coils at terminal box of each zone
A
  1. zone
  2. primary
  3. terminal reheat coil
32
Q

Single Duct: Bypass Multizone;

  1. Terminal box may be ________ type
  2. Fan arrangement is ____ ______
  3. Air supply is ______ ________
A
  1. induction type
  2. draw through
  3. constant volume
33
Q

Dual Duct System;

  1. Most ________ type of system
  2. All air system
  3. Responds to unlimited number of _____
  4. Fan arrangment can be of two types; what are they?
A
  1. expensive
  2. zones
  3. draw through or blow through
34
Q

Dual Duct System;

  1. Has two separate ducts; what are they?
  2. ________ boxes located at each zone
  3. Economizers not _________
  4. Single or _____ fan
A
  1. hot duct, cold duct
  2. Mixing
  3. recommended
  4. single or dual fan
35
Q

Name a system that is NOT energy efficient

A

single duct terminal reheat

36
Q

minimum fresh air?

A

20%

37
Q

What applications are single duct terminal reheat systems used?

A

used in large buildings with variations in load

38
Q

What type of system responds to an unlimited number of zones?

A

dual duct

39
Q

Fan arrangement for single duct bypass multizone?

A

draw through

40
Q

fan arrangement for single duct multizone?

A

blow through

41
Q

Are induction units normally used in single duct multizone?

A

no

42
Q

Where do Single Duct; Terminal Reheat Distribution; Induction Units get their primary air and induced air from?

A

primary air from main supply plenum

secondary air from primary air

43
Q

why would a single zone distribution system have a reheat coil?

A

dehumidification

44
Q

Name two types of reheat coils?

A

hot water reheat or electric reheat

45
Q

What is meant by induced air?

A

pulled in room temp air from the space

46
Q

name five air distribution arrangements:

A
  1. single zone
  2. terminal reheat
  3. induction reheat
  4. multizone
  5. bypass multi zone (terminal reheat)

Level 2: Distribution Systems (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions