Section 2 060202a-g

Question 1

How is Heat transfered

Answer 1

Warmer body to cooler body

Question 2

What are the 3 types of heat transfer?

Answer 2

Conduction
Convection
Radiation

Question 3

Explain conduction.

Answer 3

Transfer of heat from one molecule to another through direct contact (mainly solids)

Question 4

Name an excellent conductor.

Answer 4

Copper / metals

Question 5

What is an example of a poor conductor?

Answer 5

Wood

Question 6

Conduction is the primary method of heat transfer in the pipe trades. (True/ False)

Answer 6

True

Question 7

Convection if primary cause of heat loss from a building. (True/False)

Answer 7

False. (Conduction)

Question 8

Explain convection.

Answer 8

Transfer of heat within gases and liquids through differences in densities.

Question 9

What is molecular motion

Answer 9

Causes the molecules to move farther apart. (Ex. Material expands)

Question 10

What principal does a hot air balloon operate on.

Answer 10

Convection

Question 11

Hot water tanks use convection to transfer heat throughout the water. (True/False)

Answer 11

True

Question 12

Explain Radiation

Answer 12

Transmission of heat energy through a space by means of electromagnetic infrared rays.

Question 13

The sun is our primary source of ________ rays.

Answer 13

Infared

Question 14

_________heating produces a very comfortable and efficient means of heating.

Answer 14

Radiant

Question 15

What is Delta T.

Answer 15

Temperature Change.

Question 16

At what temperature is water most dense ?

Answer 16

4C (39F)

Question 17

When water changes to steam how much does it increase?

Answer 17

1700 times

Question 18

At what point does water boil?

Answer 18

100C (212F)

Question 19

When water changes to ice volume increases _______%

Answer 19

7.5

Question 20

What is a bi metal?

Answer 20

Two thin layers of different metals bonded together

Question 21

Where is a bimetal usually found?

Answer 21

Thermostats

Question 22

When is water least dense?

Answer 22

100C (212F) or Boiling Point

Question 23

In a rod and tube what part expands?

Answer 23

Tube

Question 24

Expansion and contraction can be eliminated. (True/False)

Answer 24

False. It can only be controled.

Question 25

What types of pipe has the highest rate of expansion?

Answer 25

Plastics (ABS/PVC)

Question 26

What is the formula for calculating linear expnsion?

Answer 26

Length change=lengthxCOExDT

Question 27

When piping systems are heated and cooled they ________ and _________.

Answer 27

Expand and contract.

Question 28

What are anchors, guides, piping configurations, and expansion joints used for?

Answer 28

To accommodate for expansion and contraction.

Question 29

What is axial movement?

Answer 29

Motion in a straight line (linear travel)

Question 30

What is Lateral offset

Answer 30

Where two center lines offset due to expansion. (Parallel offset or transverse motion)

Question 31

What is angular rotation

Answer 31

Radial and rotational motion. (Looks like bending)

Question 32

What are anchors

Answer 32

Anchors hold a pipe in place without letting it move.

Question 33

What are guides used for ?

Answer 33

Limit amount of deflection between anchor points.

Question 34

Smaller diameter pipe is more likely to have deflection to than to push the line straight. (True/false).

Answer 34

True

Question 35

How do you calculate the diameter of a 360° loop

Answer 35

5× pipe diameter=Radius ×2= Diameter

Question 36

Name the type of expansion joint for abs.

Answer 36

Slip or sleeve type

Question 37

An expansion joint with stabilizers (control rods) has what type of movement.

Answer 37

Axial

Question 38

What is the distance from expansion joint to pipe guide?

Answer 38

2ft (610mm)

Question 39

In an offset where should expansion happen?

Answer 39

On the fittings not pipe

Question 40

BTU

Answer 40

British Thermal Units

Question 41

KJ

Answer 41

Kilojoule

Question 42

1 ___ is required to change temp in 1 pound of water by 1 degree __________.

Answer 42

BTU, Fahrenheit.

Question 43

____KJ is required to raise 1 kilogram of water by 1 degree _______.

Answer 43

4.2, Celsius.

Question 44

Sensible Heat.

Answer 44

Change in temp, but not in state.

Question 45

Latent heat.

Answer 45

Change in state but not temp.

Question 46

3 common states of matter

Answer 46

Solid Liquid Gas

Question 47

Change from solid to liquid

Answer 47

Fusion

Question 48

Change from liquid to solid

Answer 48

Solidification

Question 49

Change from liquid to gas

Answer 49

Vaporization

Question 50

Change from gas to liquid

Answer 50

Condensation

Question 51

Specific heat capacity of water

Answer 51

1 BTU/lb°F 4.2 KJ/kg°C

Question 52

Specific heat capacity of Ice

Answer 52

.5 BTU/lb°F 2 KJ/kg°C

Question 53

Specific heat capacity of steam

Answer 53

.5 BTU/lb°F 2 KJ/kg°C

Question 54

Latent heat value ice-Water

Answer 54

144 BTU/lb 335 KJ/kg

Question 55

Latent heat value Water-steam

Answer 55

970 BTU/lb 2257 KJ/kg

Question 56

What are the sources of Heat

Answer 56

Geothermal, chemical reaction, unclear reaction, electrical energy, and mechanical energy.

Question 57

°C to °F

Answer 57

°F=(1.8×°C) +32°F

Question 58

°F to °C

Answer 58

°C= (°F-32°F) ÷1.8

Question 59

To convert °C and °F what number is used

Answer 59

Divide or multiply by 1.8 Add or subtract 32

Question 60

Sensible Heat Calculation formula

Answer 60

Specific heat capacity × mass × Delta T

Question 61

Latent Heat Calculation formula

Answer 61

Mass × applicable latent heat value

Question 62

What are Heat exchangers used for

Answer 62

To transfer heat from one medium to another

Question 63

In a heat exchanger if boiler water goes one way. What way does the domestic water go.

Answer 63

Opposite way

Question 64

How does liquid flow through a shell and tube HEX

Answer 64

Boiler water inside tubes and domestic water around tubes

Question 65

DTD

Answer 65

Design temperature difference

Question 66

ODT

Answer 66

Outside design temperature

Question 67

IDT

Answer 67

Inside design temperature

Question 68

Name two types of heat loss

Answer 68

Infiltration loss Transmission loss

Question 69

Where does infiltration loss happen

Answer 69

In every room that has a door, window, or any kind of mechanical ventilation to outdoors

Question 70

What is infiltration loss

Answer 70

Air traveling from outdoors to indoors

Question 71

What is transmission loss

Answer 71

Air conducting out

Question 72

Describe K-Value

Answer 72

Amount of BTU per hour that will be conducted through one square foot if there is a temp difference of 1 degree fahrenheit.

Question 73

How can you convert between K-Value and r-value

Answer 73

Use 1/x button on calculator

Question 74

What is u-value

Answer 74

All K-Value added together (hr/BTU)

Question 75

All measurements for heat loss calc to be within __ or ___ of a foot

Answer 75

3" or 0.25 of a foot

Question 76

What is the recommended IDT

Answer 76

72 F

Question 77

For heat loss all measurements need to be

Answer 77

In feet

Question 78

How do you find net rating

Answer 78

75% of gross rating

Question 79

What happens when a boiler is oversized

Answer 79

Cycle on and off frequently

Question 80

What is head pressure

Answer 80

Total equivalent length

Question 81

What is another method to determine total equivalent length

Answer 81

Total distance times 1.5 (extra 50% allows for friction of fittings)

Question 82

What is GPM to get laminar flow

Answer 82

2 to 4 feet per second

Question 83

What expansion tanks are considered open

Answer 83

Conventional tanks Sight glass

Question 84

What expansion tanks are considered closed

Answer 84

Diaphragm tanks

Question 85

What transfer of heat is used on baseboard heaters

Answer 85

Convection (small amount of Radiant heat)

Question 86

Where is the fan located on horizontal unit heaters

Answer 86

Behind the coil

Question 87

Where is the fan located on vertical unit heaters

Answer 87

Ahead of coil

Question 88

Where is a kickspace heater usually installed?

Answer 88

Kitchen sink

Question 89

What is MBH mean

Answer 89

Mega BTU per hour. Multiply by 1000 to get BTU per hour

Question 90

How high above a floor are unit heaters to be hung

Answer 90

6 to 12 feet

Question 91

How far from a door should a unit heater be hung

Answer 91

15 to 20 feet

Question 92

What is bouyancy

Answer 92

Force acting on any object immersed in a liquid. Object immersed appears to lose mass due to upward force of the liquid.

Question 93

What are the three laws of bouyancy

Answer 93

-A body sinks in a fluid if the mass of fluid displaced is less than the mass of the body -If a body displaces a mass of liquid greater than its own mass it will float -A body remains in equilibrium neither rising or sinking if the mass of the fluid it displaces equals its own mass

Question 94

Water displaced is due to the mass of the block (true/false)

Answer 94

False. Mass of block has no effect

Question 95

1 cubic foot of water equals a mass of?

Answer 95

62.4 lb