Test your basic knowledge |

Residential Air Conditioning

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What are the three pressures created by moving air in ductwork?
RLA/FLA x 5
30 A
Static pressure - velocity pressure - and total pressure
When it is a pull-through evaporator

2. How are round ducts connected to one another?
On the common terminal
Staples and tape
With a minimum of three evenly spaced self-tapping screws
In parallel

3. How are round ducts connected to one another?
With a minimum of three evenly spaced self-tapping screws
Dehydrated with caps on each end
When it is a pull-through evaporator
Standard

4. How is flexible duct supported?
15% silphos
A band 4 inches or more in width
Rise
8-12 degrees F

5. At what temperature does refrigerant condense in a high-efficiency unit?
Negative
Rise
20 degrees above ambient
Over 800 degrees F

6. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
L-type
200
Individual return air systems and central return air systems
By increasing the surface of the condenser coil

7. The evaporator is designed to remove what two types of heat?
Pull a vacuum
Inches of water column (in. WC)
It will have a decrease in superheat
Latent and sensible

8. On what terminal do you check amperage?
Common
Below 800 degrees F
Compressor
100

9. 13 SEER is classified as what kind of efficiency?
By increasing the surface of the condenser coil
False
High
Fiberglass

10. How does ACR copper pipe come?
They are larger
A piston type metering device
Dehydrated with caps on each end
Any amount

11. Can refrigerant line sets be altered in length?
Individual return air systems and central return air systems
Yes
Compressor
The suction line or the low-pressure side

12. 9' round duct has a ballpark cfm of what?
Boil the liquid refrigerant out ot the oil within the crankcase
30 degrees F
100
300

13. What sort of pressure will a push-through evaporator have?
Duct with insulation on the inside
TXV
With 4' saddles
Positive

14. How are the condenser coils different on a high-efficiency unit?
45-55%
They are larger
A diffuser
4

15. At what temperature does refrigerant condense in a high-efficiency unit?
Positive
40 degrees F
20 degrees above ambient
It rises

16. What is the range for normal superheat and subcooling?
A dirty evaporator
Positive
Pistons
8-12 degrees F

17. What are the two basic duct connection configurations for package units supply and return air ducts?
25-ft or 50-ft
On the common terminal
A diffuser
Over/under and side by side

18. What do you use to check for leaks?
By increasing the surface of the condenser coil
Btu/hr (output) / wattage (input)
Nitrogen with a small amount of refrigerant
Any amount

19. Do you need a vent on a push-through evaporator?
Dehydrated with caps on each end
When it is a pull-through evaporator
Yes
Inside diameter (ID)

20. What is a package unit?
Before the vent
TXV
They are larger
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

21. What kind of refrigeratnts must be added in liquid form?
Outside diameter (OD)
Blended refrigerants
Heat load
100

22. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
Pi x radius squared
25-ft or 50-ft
True
Any amount

23. What is a package unit?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
On the common terminal
The takeoff fitting
Outside diameter (OD)

24. What are the two functions of the air-conditioning system?
Inclined manometer
Potential relay and start capacitor
Yes
To remove humidity and lower dry bulb temperature

25. What are the three ways a motor can fail electrically?
Inclined manometer
Pistons
Shorted winding - open winding - and grounded winding
High

26. What are the two types of return air systems in residential installations?
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
Individual return air systems and central return air systems
Negative
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

27. What tool is used to expand the diameter of soft copper tubing
A swaging tool
Blended refrigerants
Potential relay and start capacitor
With an are rating

28. 13 SEER is classified as what kind of efficiency?
High
15 A
Dehydrated with caps on each end
Inside diameter (ID)

29. How do you achieve high-efficiency?
By increasing the surface of the condenser coil
TXV
105 degrees F
Standard

30. The crankcase heater on an air-conditioning compressor is used to what?
Below 800 degrees F
A band 4 inches or more in width
Boil the liquid refrigerant out ot the oil within the crankcase
Inclined manometer

31. Most duct insulation is made of what?
Fiberglass
Blended refrigerants
True
30-35 degrees above ambient

32. If the suction pressure rises - what happens to the head pressure?
140 degrees F
Outside of the male fitting
On the common terminal
It also rises

33. At what temperature does refrigerant condense in a standard-efficiency unit?
No
150
30-35 degrees above ambient
6

34. The furnace size is calculated by what?
Heat loss
A swaging tool
It will be low
When it is above a conditioned space

35. 8' round duct has a ballpark cfm of what?
200
S-clips and drives (cleats)
Individual return air systems and central return air systems
40 A

36. 8' round duct has a ballpark cfm of what?
150
105 degrees F
200
To lower the amount of pressure drop through the coil

37. Can refrigerant line sets be altered in length?
30 degrees F
Yes
TXV
Compressor

38. How does ACR copper pipe come?
Duct with insulation on the inside
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Dehydrated with caps on each end
8-12 degrees F

39. What kind of metering device do high-efficiency units usually use?
TXV
Latent and sensible
8
Blended refrigerants

40. In what length rolls is soft copper tubing normally available?
Yes
Infiltration and ventilation
25-ft or 50-ft
A dirty evaporator

41. At what temperature will soft solder melt?
100
L-type
Below 800 degrees F
Shorted winding - open winding - and grounded winding

42. Do you need a trap on a pull-through evaporator?
30 A
Slugging
Yes
Shorted winding - open winding - and grounded winding

43. How is the high pressure switch wired with the low pressure switch?
In parallel
A diffuser
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
100 psig

44. On what terminal do you check amperage?
A dirty evaporator
Common
A bypass duct or a dump zone
TXV

45. At what temperature will soft solder melt?
Below 800 degrees F
Yes
Belt drive and direct drive
Common

46. When must a copper joint never be soldered or brazed?
Shorted winding - open winding - and grounded winding
Yes
When the system is under pressure
Common

47. What kind of copper tubing is used for refrigeration or air-conditioning applications?
It rises
105 degrees F
ACR (air-conditioning refrigeration) tubing
Nominal-sized tubing

48. What are the four materials used to make duct?
With a minimum of three evenly spaced self-tapping screws
In parallel
Duct - electrical - and mechanical
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

49. How many amps can 12 g wire handle?
400
400
20 A
40 degrees F

50. Pressure in ductwork is measured In what?
45-55%
Boil the liquid refrigerant out ot the oil within the crankcase
Inches of water column (in. WC)
Positive