ICA Module 2 Section 2 Air Conditioning

Question 1

List at least 10 items that affect the amount of air-conditioning needed in a home

Answer 1

outdoor temp, outdoor humidity, level of insulation in home, air gaps, how many panes are in windows

Question 2

How many square feet can 1 ton of air-conditioning cool in Florida?

Answer 2

450-700 sqft

Question 3

How many square feet can 1 ton of air-conditioning cool in Michigan?

Answer 3

700-1000 sqft

Question 4

Oversized distribution ductwork is a common problem with central air-conditioning. T/F

Answer 4

False

Question 5

An undersized air conditioner is better than an oversized one. T/F

Answer 5

True

Question 6

The typical temperature drop from outdoors to indoors with a properly operating air-conditioning system would be about 15 degrees F. T/F

Answer 6

True

Question 7

What kind of temperature drop would you expect to find in the house air as it passes over the evaporator coil?

Answer 7

15 degrees

Question 8

A compressor can be thought of as a pump. T/F

Answer 8

True

Question 9

Compressors are typically located indoors on an air-to-air split system air-conditioning system. T/F

Answer 9

False

Question 10

What is the function of a sump or a crankcase heater?

Answer 10

Keeps oil warm enough to boil off refrigerant

Question 11

List 8 common compressor problems.

Answer 11

excess noise, short cycling, not level, wrong breaker size, not cooling, not working

Question 12

The condenser coil in a split system is typically located ___.

Answer 12

in cabinet (condenser unit)

Question 13

The evaporator coil in a split system is typically located _____.

Answer 13

just past furnace heat exchanger

Question 14

The condenser fan in a split system is located _____.

Answer 14

in front of compressor & condenser coil

Question 15

List 4 condenser-coil problems.

Answer 15

dirty, damaged, corrosion, dryer exhaust too close

Question 16

List 3 common configurations of evaporator coils.

Answer 16

A coil, N coil, Slab coil

Question 17

Evaporator coils should be upstream of furnace heat exchanges. T/F

Answer 17

False

Question 18

List 6 common evaporator problems.

Answer 18

no access to coil, dirty, frost, damage, corrosion

Question 19

In one sentence, describe the function of a capillary tube.

Answer 19

expansion device

Question 20

In one sentence, describe the function of a thermostatic expansion valve.

Answer 20

metering device

Question 21

List 4 common expansion device problems

Answer 21

capillary tube defects, loose, clogged, sticking

Question 22

List 5 possible causes of leaking condensate drain pans

Answer 22

rust, cracks, dirt accumulation, improper slope

Question 23

When is an auxillary condensate drain pan needed?

Answer 23

above finished living space

Question 24

What are condensate drain lines usually made of?

Answer 24

plastic, copper

Question 25

Do condensate drain lines ever have a trap?

Answer 25

Yes

Question 26

What is the purpose of the condensate trap?

Answer 26

use weight of water to stop the flow of air (like a P-trap)

Question 27

List 2 acceptable discharge points for condensate drain lines & 1 generally unacceptable discharge point.

Answer 27

Acceptable=sink, floor drain Not Acceptable=through floor (slab)

Question 28

List 3 common condensate pump problems

Answer 28

not working, leaking, poorly wired

Question 29

Refrigerant lines are usually made of ___

Answer 29

copper

Question 30

The larger refrigerant lines contains a liquid T/F

Answer 30

False

Question 31

The smaller refrigerant line is called the suction line. T/F

Answer 31

False

Question 32

The larger refrigerant line is called the return line. T/F

Answer 32

True

Question 33

List 5 common refrigerant line problems.

Answer 33

leaking, damage, missing insulation, too warm/cold, too c?

Question 34

How would you normally identify a leak in a refrigerant line visually?

Answer 34

oil residue

Question 35

Which line should be cold when the system is operating?

Answer 35

suction/return line (large line)

Question 36

Which line should be warm when the system is operating?

Answer 36

liquid line (small line)

Question 37

Which line should be insulated?

Answer 37

suction line (large line)

Question 38

Where is the condenser fan in a split system located?

Answer 38

condenser cabinet

Question 39

What is the typical inlet & outlet temperature of air across the condenser fan?

Answer 39

20 & 50 degrees

Question 40

List 4 common condenser-fan problems.

Answer 40

noisy, not working, corrosion, obstructed air flow

Question 41

Where is the evaporator fan typically located in a split system?

Answer 41

inside air handler (inside house)

Question 42

The amount of air that must cross an evaporator coil in a heating climate is less than the amount of air that must cross a conventional furnace heat exchanger coil. T/F

Answer 42

?

Question 43

Oversized ducts are a common problem. T/F

Answer 43

False

Question 44

High-level returns are more appropriate for heating than cooling. T/F

Answer 44

False?

Question 45

Ducts passing through unconditioned spaces such as attics or crawlspaces should be _____.

Answer 45

insulated & air tight

Question 46

List 7 common problems with thermostats

Answer 46

not working, loose, dirty, damaged, not level, poor location

Question 47

How long do air-conditioning systems typically last in your area?

Answer 47

10-15 years

Question 48

What is the typical warranty period for a compressor?

Answer 48

10 years

Question 49

Heat pumps are generally sized based on: A. heating load B. cooling load C. other

Answer 49

A-heating load (capacity)

Question 50

The implication of an oversized heat pump during the summer months is what?

Answer 50

damp climate indoors

Question 51

You should not operate the heat pump in the heating mode when the outdoor temperature is above _____.

Answer 51

65 degrees

Question 52

You should not operate the heat pump in the cooling mode when the outdoor temperature is below _____.

Answer 52

65 degrees

Question 53

List at least 8 clues that would suggest that you are looking at a heat pump rather than a central air-conditioning system.

Answer 53

data plate, if thermostat has emergency heat setting, 2 stage thermostat, both lines are insulated, reversing valve present, 2 expansion devices, compressor indoors, outdoor thermostat, operated in winter

Question 54

List 7 common heat pump problems distinct from common air-conditioning problems.

Answer 54

oversized for cooling/undersized for heating, inoperative, poor control coil location, coil iced up, air flow problems, no back up heat, old