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. 10' round duct has a ballpark cfm of what?
Staples and tape
When it is above a conditioned space
By increasing the surface of the condenser coil
400

2. How do you calculate EER?
Btu/hr (output) / wattage (input)
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Latent and sensible
Indoor fan motor - outdoor fan motor - and the compressor

3. The compressor is cooled by liquid refrigerant. (True of False)
40 degrees F
ACR (air-conditioning refrigeration) tubing
140 degrees F
False

4. What is the difference between SEER and EER?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Pull a vacuum
Duct - electrical - and mechanical
SEER includes the energy used in the start-up and shut-down cycles

5. What is the range for normal superheat and subcooling?
100
8-12 degrees F
40 degrees F
Positive

6. When do you install a trap on a drain line?
Side-by-side and over-and-under
Inside diameter (ID)
When it is a pull-through evaporator
100

7. What are the four materials used to make duct?
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
It rises
Indoor fan motor - outdoor fan motor - and the compressor
Pistons

8. Where do you apply flux when soldering?
Outside of the male fitting
Infiltration and ventilation
Average feet per minute X area in square feet (H' x W'/144)
Negative

9. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
Duct - electrical - and mechanical
Shorted winding - open winding - and grounded winding
High
L-type

10. How is insulation around a duct rated?
Yes
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
With an are rating
S-clips and drives (cleats)

11. How many amps can 8 g wire handle?
The takeoff fitting
40 A
Positive
Standard

12. Sections of duct board can be fastened together with what?
In parallel
High
A swaging tool
Staples and tape

13. In what length rolls is soft copper tubing normally available?
Fiberglass
25-ft or 50-ft
40 A
To lower the amount of pressure drop through the coil

14. The load on the evaporater will effect which pressure?
20 degrees F
6
Suction
With a minimum of three evenly spaced self-tapping screws

15. Where do you apply flux when soldering?
2 minutes
Outside of the male fitting
To lower the amount of pressure drop through the coil
20 degrees above ambient

16. How will too much refrigerant effect subcooling?
45-55%
Vapor
Over/under and side by side
It will be high

17. The refrigerant within the evaporator will typically boil at what temperature when it is 75 degrees inside with a relative humidity of 50%?
A band 4 inches or more in width
40 degrees F
Over 800 degrees F
True

18. What is used to measure static air pressure in ducts.
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Compressor
Boil the liquid refrigerant out ot the oil within the crankcase
Inclined manometer

19. What are the three major power-consuming devices on an air-conditioning system?
Indoor fan motor - outdoor fan motor - and the compressor
100 psig
400
Duct with insulation on the inside

20. Why is it necessary to have multiple refrigerant circuits in some evaporator coils?
With an are rating
1/4'
To lower the amount of pressure drop through the coil
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

21. Where do you install a trap on a drain line?
On the common terminal
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Compressor
Before the vent

22. 6' round duct has a ballpark cfm of what?
100
With an are rating
TXV
To lower the amount of pressure drop through the coil

23. What is the name of the fitting where the branch line leaves the duct?
4
8-12 degrees F
The takeoff fitting
Subtract ambient temperature from 100

24. What is the difference between SEER and EER?
25-ft or 50-ft
S-clips and drives (cleats)
SEER includes the energy used in the start-up and shut-down cycles
TXV

25. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
45 degrees F
8
True
In series

26. What sort of pressure will a pull-through evaporator have?
Standard
With an are rating
Negative
15 A

27. 13 SEER is classified as what kind of efficiency?
It rises
They are larger
High
Inclined manometer

28. What is used to measure static air pressure in ducts.
105 degrees F
Inclined manometer
With 4' saddles
Nitrogen with a small amount of refrigerant

29. If the rpm's are 3450 - how many poles does the motor have?
Suction
2
When the system is under pressure
Infiltration and ventilation

30. What is the typical pressure differance across a TXV?
Duct - electrical - and mechanical
Standard
30 degrees F
100 psig

31. What component changes refrigerant from a low pressure gas to a high pressure gas?
Yes
Compressor
40 degrees F
Yes

32. Sections of duct board can be fastened together with what?
6
15 A
Nominal-sized tubing
Staples and tape

33. Do you need a trap on a pull-through evaporator?
Yes
In series
Yes
They are physically larger

34. When do you install a trap on a drain line?
Below 800 degrees F
Infiltration and ventilation
Duct - electrical - and mechanical
When it is a pull-through evaporator

35. How many BTU's per ton?
Individual return air systems and central return air systems
12000
15 A
By increasing the surface of the condenser coil

36. If the rpm's are 3450 - how many poles does the motor have?
30 degrees F
2
On the common terminal
20 degrees F

37. At what temperature will brazing melt?
45-55%
Blended refrigerants
Below 800 degrees F
Over 800 degrees F

38. What are the four materials used to make duct?
4
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Positive
8

39. What component changes refrigerant from a low pressure gas to a high pressure gas?
2
High
Compressor
Over/under and side by side

40. How many amps can 10 g wire handle?
30 A
When the system is under pressure
They are larger
30-35 degrees above ambient

41. What are the two functions of the air-conditioning system?
Indoor fan motor - outdoor fan motor - and the compressor
To remove humidity and lower dry bulb temperature
20 A
18 gauge

42. What kind of copper tubing is used for refrigeration or air-conditioning applications?
ACR (air-conditioning refrigeration) tubing
40 A
Average feet per minute X area in square feet (H' x W'/144)
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

43. What distributes supply air to a room in a structure?
Pi x radius squared
105 degrees F
40 degrees F
A diffuser

44. In what length rolls is soft copper tubing normally available?
30-35 degrees above ambient
A band 4 inches or more in width
25-ft or 50-ft
A diffuser

45. What do you use to connect square and rectangular ductboard together?
400
S-clips and drives (cleats)
Heat loss
Shorted winding - open winding - and grounded winding

46. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
Any amount
Suction
A swaging tool
45-55%

47. How do you achieve high-efficiency?
6
Vapor
By increasing the surface of the condenser coil
TXV

48. Superheat should never be below how many degrees
300
When it is above a conditioned space
High
5 degrees

49. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
45-55%
A band 4 inches or more in width
15% silphos
A piston type metering device

50. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
Any amount
105 degrees F
Common
100 psig