Air condition

Question 1

List 6 common evaporator problems.

Answer 1

1. no access to coil
2. dirty
3. frost
4. top of evaporator dry
5. corrosion腐蚀
6. damage

Question 2

Oversized distribution分布 ductwork is a common problem with central air conditioning? True or False

Answer 2

False

Question 3

An undersized air conditioner is better than an oversized one. True or False?

Answer 3

T

Question 4

The typical temperature drop from outdoors to indoors with a properly operating air conditioning system would be about 15 degrees? True or False

Answer 4

T

Question 5

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

Answer 5

15-20

Question 6

A compressor can be thought of as a pump? True or False

Answer 6

T

Question 7

What is the function of a sump or crankcase heater?

Answer 7

It keeps the oil at the base of the compressor warm enough to boil off the refrigerant

Question 8

List eight common compressor problems

Answer 8

1. Excessive过度 noise/vibration震动
2. Short cycling or running continuously
3. Out of level
4. Wrong fuse or breaker size
5. Electric wires too small
6. Missing electrical shut off
7. Inoperative不工作
8. Inadequate不足 cooling

Question 9

The condenser coil in a split system is typically located________?

Answer 9

Outdoors

Question 10

List three common configurations of evaporator coils

Answer 10

1. A coil
2. Slab Coil
3. Vertical coil

Question 11

Evaporator coils should be upstream of furnace heat exchangers. True or False.

Answer 11

False

Question 12

In one sentence describe描述 the function of a capillary毛细管 tube

Answer 12

The capillary tube acts as an obstruction障碍物 in the line, reducing减少 the pressure and temperature of the liquid refrigerant制冷剂

Question 13

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

Answer 13

A TXV, or TEV acts as a more precise精确的 expansion device on larger air conditioners调节器 or heat pumps.

Question 14

List 4 common expansion device problems.

Answer 14

1. capillary tube defect
2. thermostatic expansion valve connections loose
3. clogged orifice孔
4. expansion valve 黏贴

Question 15

List 7 possible causes of leaking condensate drip pans

Answer 15

1. The pan may be cracked, or have an open seam in it
2. The opening to the drain line may be obstructed堵塞
3. The drain line may be missing or disconnected
4. The pan may not be sloped properly allowing water to overflow rather than run to the drain
5. The pan may be rusted through
6. The pan may not be properly located below the coil
7. The pan may be filled with debris碎片, restricting限制 the amount of water it can hold

Question 16

When is an auxiliary辅助的 condensate冷凝 drain pan needed?

Answer 16

When the evaporator coil is located in an attic or anywhere over a finished living space.

Question 17

What are condensate drain lines usually made of?

Answer 17

plastic or copper

Question 18

Do condensate drain lines ever have a trap?

Answer 18

Condensate lines from the primary pan may or may not have a trap. Lines from secondary pans should never be trapped.

Question 19

What is the purpose of a trap on a condensate drain line?

Answer 19

1. The trap may be required if the condensate pan is upstream of the house air fan because the water is under negative pressure
2. If the condensate is allowed directly into waste plumbing, a trap is required

Question 20

List two acceptable discharge points for condensate drain lines and one generally unacceptable discharge point

Answer 20

Acceptable

1. Outside the building directly into the ground
2. Near the basement floor drain (must be an air gap)

Unacceptable

1. Into the granular fill beneath the basement floor slab
2. Into the waste plumbing stack

Question 21

List three common condensate pump problems.

Answer 21

1. Inoperative不工作
2. Leaking
3. Poor wiring

Question 22

Refrigerant lines are usually made of________?

Answer 22

Copper

Question 23

The larger line contains a liquid? True or false

Answer 23

False

Question 24

The smaller line is called the suction line. True or False?

Answer 24

False

Question 25

The smaller line is called the suction line. True or False?

Answer 25

False

Question 26

The larger line is called the return line. True or False? true

Answer 26

true

Question 27

List 5 common refrigerant line problems

Answer 27

1. leaking 2. damage 3. missing insulation 4. lines too warm or cold 5. lines touching each other

Question 28

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

Answer 28

This may be identified确定 by an oil residue残留 below the line set, typically at the valves or coil connections

Question 29

Which line should be cold when the system is operating?

Answer 29

Suction line AKA return line (large insulated one)

Question 30

Which line should be warm when the system is operating?

Answer 30

Liquid line (Smaller uninsulated line)

Question 31

Which line should be insulated

Answer 31

Suction AK Return line

Question 32

Where is the condenser fan in a split system located?

Answer 32

outdoors in the condenser unit

Question 33

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

Answer 33

The inlet temperature is outdoor air temperature, and outlet temperature is roughlyd大约 15-20 degrees F higher than the outdoor temperature

Question 34

Oversized ducts are a common problem. True or False?

Answer 34

False

Question 35

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

Answer 35

Indoors

Question 36

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传统 furnace heat exchanger coil. True or False

Answer 36

False

Question 37

High level returns are more appropriate适当的 for heating than cooling. True or False?

Answer 37

False

Question 38

Ducts passing through unconditioned spaces should as attics and crawlspaces should be \_\_\_\_\_\_\_\_\_\_\_\_.

Answer 38

Insulated, with appropriate适当的 vapor barriers

Question 39

How long do air conditioning compressors typically last in your area?

Answer 39

8-10 years southern USA 10-15 years Moderate climates 15-20 years Northern climates

Question 40

What is the typical warranty period for a compressor?

Answer 40

typically 5 years

Question 41

Heat pumps are generally sized based on the ?

Answer 41

Cooling load

Question 42

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

Answer 42

It would cool the house down too fast without dehumidifying除湿 the air resulting in a cool damp environment客观环境.

Question 43

You should not operate the heat pump in the heating mode when the outdoor temperature is above ________ degrees?

Answer 43

65

Question 44

List 9 clues that would suggest that you are looking at a heat pump rather than da central air conditioning system

Answer 44

1. Data plate may say "HP" or "Heat pump" 2. Thermostat has an emergency heat setting 3. Both refrigerant lines are insulated 4. Presence of a reversing valve 5. Compressor is indoors and it's an air to air system 6. Presence of an outdoor thermostat connected to control wiring 7. If it is winter and the unit is operating its heat pump 8. You find a two-stage thermostat 9. You find two expansion devices

Question 45

Common air conditioner thermostat problems include all of the following except?

Answer 45

Poor location Not level Loose Wrong size

Question 46

Which of the following is not a common problem with an air conditioner compressor? Out of level Excess超额 noise or 震动 Short cycling or running continuously Overcooling the refrigerant制冷剂 in the condenser

Answer 46

Overcooling the refrigerant制冷剂 in the condenser

Question 47

What is an evaporative cooler?

Answer 47

A unit that is a box shaped appliance with one or more porous多空 surfaces that enable air to pass through a fan inside the unit, Pulls outside air through the sides and into the house

Question 48

What is the difference between a evaporative cooler and an air conditioner? 蒸发冷却器和空调有什么区别？

Answer 48

Evaporative coolers cool air by filtering it through water, thus lowering its temperature. Air conditioning works by taking the humidity out of the home 蒸发冷却器通过过滤水来冷却空气，从而降低其温度。空调的工作原理是把家里的湿气带走

Question 49

What is the major advantage优势 of an evaporative蒸发 cooler?

Answer 49

Operating cost are typically 1/2 of a central Air conditioner.

Question 51

how do you determine if the evaporator cooler is the correct size for the home?

Answer 51

Check to see if the motor is 1 or two speed verify how many cubic feet of air per minute the cooler can pump and compare比较 that against how many cubic feet the home is.