Solar

Question 1

When installing a solar collector, what is the best way to place the tilt

Answer 1

15% W plus the latitude facing south

Question 2

in a temperate region, which side of the house should you install the least number of windows to help keep the cold out in the winter

Answer 2

North

Question 3

if a solar heating system is not used, how much heat loss shold the auxilary system compensate for

Answer 3

100%

Question 4

in an all air solar heating system, which of the following is not part of the apparatus

Answer 4

hot water boiler

Question 5

a solar unit when installed on the ground should

Answer 5

be placed on a concrete pad

Question 6

solar collectors should be placed facing

Answer 6

latitude south

Question 7

for the best orientation in order to achieve the greatest efficiency, a solar collector on the ground should be placed

Answer 7

facing south and a little west

Question 8

when designing a solar system, the first step is

Answer 8

-selection of collector size
-storage capacity
-layout of system
-estimating daily demand

Question 9

in sizing a solar system, the first item of importance is

Answer 9

determining the BTU/hr load requiremetn

Question 10

“Life Cycling costing” as related to the design of a solar heating system is

Answer 10

-cost of auxilary energy
-the initial cost of the sytem
-the life expectancy of the system

Question 11

when installing a solar system, what aspects should be considered

Answer 11

-operating cost
-the gas or liquid system
-the initial cost
-the passive or active system

Question 12

what climatic conditions shold be considered in solar energy installation

Answer 12

-freezing
-insufficient sunlight

Question 13

how do you size the solar heating system

Answer 13

for the BTU/hr required

Question 14

what is the measurement for heat

Answer 14

BTu

Question 15

in solar heating, where is the heat exchanger placed in relation to the refrigeration or evaportator coil

Answer 15

before the coil

Question 16

if you have a closed solar water heating system you will need

Answer 16

an expansion tank

Question 17

if a closed looped piping system is used with the collector, which of the following must also be used

Answer 17

expansion tank

Question 18

what is the most imporant component in the effiecy of a hot water solar heating system

Answer 18

Solar panels

Question 19

water type solar flat place collectors use water as the heat transfer medium this is known as

Answer 19

hydronic system

Question 20

____ CFM of air are required per cubic foot of collector

Answer 20

30.00

Question 21

collectors mounted above roofing have an allowance of approximately

Answer 21

1-1/2” clearance

Question 22

most flat plate collectors use ____ as the heat transfer medium

Answer 22

-oil
-antifreeze
-water
-gas

Question 23

the requiremetn for an 800 sq ft collector is

Answer 23

1200 to 1600 gallon storage capacity

Question 24

the optimum or ideal tilt angle for the solar collectors for year round hot waer is

Answer 24

30-45

Question 25

using water as teh heat transfer liquid in the collector loop, what is the gallon flow per hour over a 1 foot square area of collector

Answer 25

1 to 2 gallons

Question 26

liquid collectors which contain small passages are

Answer 26

susceptible to plugging

Question 27

the heat transfer fluid most commonly used for a solar sytem is

Answer 27

water

Question 28

for heat exchanger effectiveness, a heat transfer coefficient of at least ____ should be achieved

Answer 28

10 degrees F

Question 29

the metal used for an absorber plate (flat plate collector) is usually

Answer 29

-copper -stainless steel -mild carbon steel -aluminium

Question 30

the surface coating normally used for an absorber plate is

Answer 30

-anodize -copper oxide -black chrome or nickel -black paint - inorganic, acrylic, silicon

Question 31

the size of the solar hot water storage tank should be approximately

Answer 31

1 to 2 gallons for every sq ft of collector

Question 32

on a coil in tank heat exchanger, does the coil have to be on the top or on the bottom of the storage tank

Answer 32

bottom of tank

Question 33

in solar heating the heat exchanger is used to

Answer 33

transfer heat from one material to another

Question 34

in reference to a solar storage sytem, phase change means

Answer 34

heat of fusion

Question 35

which of hte following storage sytems requires the smallest storage tank size for solar water heating

Answer 35

phase change (salts)

Question 36

how do you prevent steam flash from the top of the collector

Answer 36

provide a pressure relief valve

Question 37

what is the single largest cause of corrosion problems

Answer 37

incompatibility of the piping materials with the transfer fluid

Question 38

if you have solar collectors mounted in array they should be mounted so that they can

Answer 38

be taken apart easily

Question 39

what type of heat storage system can you use on an air type of solar heating system

Answer 39

crushed rock or pebbles

Question 40

what type of storage system for the storage of heat can you used on a liquid type of solar heating system

Answer 40

-water tank -salts -crushed rock -pebbles

Question 41

the approximate fluid flow rate of gallons per minute over 1 square foot of solar collector is

Answer 41

.02 gallons per minute

Question 42

if you are getting steam in your hot water system, what do you look for

Answer 42

automatic mixing valve

Question 43

if the water comes too hot from the collector stroage tank to the hot water tank, what would the automatic mixing valve do

Answer 43

temper the water

Question 44

in order to prevent water from flashing to steam at teh top of a collector the

Answer 44

balance valves are adjusted

Question 45

if the water comes too hot from the storage tank to the hot water tank, what would the automatic mixing valve do

Answer 45

add cold water

Question 46

what do you do to keep scalding water out of your domestic hot water supply

Answer 46

use a thermostatic control mixing valve

Question 47

anti-freeze solution used in the solar water heating system should be checke

Answer 47

for freezing and ph annually

Question 48

individual collectors in a series must be

Answer 48

accessible for repairs and replacement

Question 49

what is the specific heat of water

Answer 49

1 BTU per/lb per degree of F rise

Question 50

in an air duct, the free space is known as the

Answer 50

K factor

Question 51

the specific fheat of water equals ____ BTU per/lb per degree of F rise

Answer 51

1

Question 52

one psi is

Answer 52

2.31 feet in height of water

Question 53

the main advantage of a passive solar system over an active solar system is

Answer 53

-cost -number of working parts -reliablity

Question 54

what type of thermostat would you have on a solar system

Answer 54

two stages

Question 55

insulating of pipes is needed in a liquid working fluid solar heating sytem to

Answer 55

transport fluids by conserving heat loss

Question 56

The ____ determine the mode of operation of a solar air heating system

Answer 56

collectors

Question 57

the temperature differential between the collector and the storage tank is

Answer 57

10 degrees to 20 degrees

Question 58

the most common cause of an inefficient solar system is

Answer 58

improperly insulated pipes

Question 59

____ is not included in a solar system

Answer 59

boiler

Question 60

air filters in a solar system need to be changed

Answer 60

monthly

Question 61

a phase-change is

Answer 61

a fusion of heat

Question 62

which valve is used to control the flow of liquid in one direction only

Answer 62

check

Question 63

what factors are used to determine to the cost effectiveness of a solar system

Answer 63

-initial cost -life cycle of the system -alternate sources of energy

Question 64

the buildin ____ controls the dampers of a solar air heating system

Answer 64

thermostat

Question 65

in a solar system, a thermostat governed by an on-off differential control monitors the air temperature in

Answer 65

the collector outlet manifold

Question 66

what are some of the things to look out for when mounting the collectors on the roof

Answer 66

-ice blockages -snow drifiting -leaves -electric wires

Question 67

what is the primary in designing a solar system

Answer 67

BTU demand

Question 68

what creates corrosion in the pipes of the solar system

Answer 68

-dissimilar metals in the piping -interaction of the metals of the piping and the heat transfer fluid

Question 69

to avoid boiling, where excessive pressures can develop in a solar system, adequately sized devices are needed such as

Answer 69

pressure relief valves

Question 70

thermosiphon and bread box solar heating systems are more effective to instll than active pump systems because

Answer 70

-installation is always more difficult in pumped systems -initial costs are lowered

Question 71

on a thermosiphon water heater system, where should the water storage tank be located in relation to the solar collector

Answer 71

1 to 2 feet above the collector

Question 72

solar system corrosion is aused by

Answer 72

-insulation that is not effective durable or compatible for the designed conditions -pool composition of the metals or alloys -the type of material specified for the system are not compatible for the fluids -water composition and leakage

Question 73

freeze-up and/or lessened operating efficiency may occur in liquid installation if which of the following is overlooked

Answer 73

inadequate pipe insulation

Question 74

what is the purpose of collector glazing

Answer 74

-it allows for transmission of solar radiation to the collector absorber surface -it reduces convection heat losses to the surrounding air -it absorbs the infrared (long wave length) radiation that would otherwise radiate back into the envirnoment from the absorber surface

Question 75

internal failure in a solar system through corrosion is caused by

Answer 75

incompatibility material with heat transfer fluid

Question 76

the collectors should be balanced so that the flow rates through them are

Answer 76

plus or minus 20% of design value

Question 77

insulation of solar hot lines is necessary to prevent

Answer 77

personal injury

Question 78

what is the specific grvity of water

Answer 78

1

Question 79

a mass of water compared to the same open air mass of rocks or pebbles will hold how much more heat

Answer 79

five times

Question 80

collectors should be installed

Answer 80

to minimize ice dams

Question 81

es should be planted near solar collector panels (t/f)

Answer 81

False

Question 82

what is the maximum BTU/h per sq ft of surface absorbed by many flatplate collectors

Answer 82

250

Question 83

what is the most feasible use of solar heating from an energy conservation standpoint in residential aplication

Answer 83

Domestic hot water

Question 84

how many factors should be considered in determining the feasibility of a residential solar space heating system

Answer 84

5

Question 85

what percentage of the total heating load is usually practical for the solar heating supplement

Answer 85

50-70

Question 86

air and liquid are the two most practical methods of transferring heat from the sun to residential spce heating (T/F)

Answer 86

True

Question 87

what is done with excess solar heat not used immediatly for space heating

Answer 87

it is stored

Question 88

which occupies mroe space for the same number of BTU stored, rock or water

Answer 88

rock

Question 89

what is the specific heat of rock

Answer 89

.2

Question 90

what solution can be used in a liquid system to prevent freeze up

Answer 90

Ethylene glycol

Question 91

what is the best direction for a residential heating flat-plate collector

Answer 91

Latitude + 15 degrees

Question 92

low temperature collectors are normally unglazed, flat collectors intended to operate at temperatures of about

Answer 92

15 to 100 degrees above ambient temperature

Question 93

medium temperature collectors are flat plate collectors enclosed in an insulated case with one or two glazings. The intended temperature range of operation is about

Answer 93

15 to 200 degrees above ambient temperature

Question 94

high temperature collectors have some overlap from flat plate collectors with selective absorber plates and heavy insulation. some may be enhanced by the installation of a sun tracking system. which of the following best defines the high temperature collector variations

Answer 94

-parabolic dis reflectors -evacuated tube flat plates -parabolic through types

Question 95

unglazed plat-plate liquid collectors are most commonly used for

Answer 95

swimming pools and hot water tanks

Question 96

solar panels should be placed on a roof at which of the following angles

Answer 96

equal to the latitude

Question 97

an air solar system can be designed with a pressure drop of how many inches of water

Answer 97

1

Question 98

with an air movement of 15-25 feet per minute, people are most comfortable in the summer at a temp of

Answer 98

71 degrees