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 is lined duct?
45-55%
Duct with insulation on the inside
1/4'
25-ft or 50-ft

2. What kind of refrigeratnts must be added in liquid form?
Outside of the male fitting
Blended refrigerants
Individual return air systems and central return air systems
45-55%

3. The A/C size is calculated by what?
Heat load
They are physically larger
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Fiberglass

4. How many amps can 14 g wire handle?
RLA/FLA x 5
Heat load
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
15 A

5. How is the high pressure switch wired with the low pressure switch?
Shorted winding - open winding - and grounded winding
The takeoff fitting
In parallel
Fiberglass

6. The evaporator is designed to remove what two types of heat?
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Dehydrated with caps on each end
Latent and sensible
Positive

7. Will a dirty condenser cause a rise or fall in pressure?
Shorted winding - open winding - and grounded winding
Fiberglass
To remove humidity and lower dry bulb temperature
Rise

8. What are the two basic duct connection configurations for package units supply and return air ducts?
Over/under and side by side
When it is a pull-through evaporator
ACR (air-conditioning refrigeration) tubing
Rise

9. What is it called when liquid refrigerant gets into the compressor?
Slugging
S-clips and drives (cleats)
Yes
In series

10. How will too much refrigerant effect subcooling?
Heat loss
It will be high
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Inclined manometer

11. What are the two types of blower drives?
On the common terminal
8-12 degrees F
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
Belt drive and direct drive

12. What is the normal evaporator temperature?
Blended refrigerants
By increasing the surface of the condenser coil
400
45 degrees F

13. How is nominal-sized tubing sized?
Rise
A piston type metering device
Inside diameter (ID)
To lower the amount of pressure drop through the coil

14. Why are some ACR tubing lines insulated?
Side-by-side and over-and-under
40 degrees F
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
Compressor

15. What is a package unit?
Slugging
Static pressure - velocity pressure - and total pressure
A diffuser
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

16. What sort of pressure will a push-through evaporator have?
Subtract ambient temperature from 100
Positive
Negative
Slugging

17. How is ACR tubing sized?
25-ft or 50-ft
Inside diameter (ID)
Outside diameter (OD)
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

18. The load on the evaporater will effect which pressure?
Outside diameter (OD)
Suction
L-type
With an are rating

19. What are the two functions of the air-conditioning system?
Common
To remove humidity and lower dry bulb temperature
20 degrees above ambient
Average feet per minute X area in square feet (H' x W'/144)

20. How are high-efficiency condenser coils different from standard-efficiency condenser coils?
Average feet per minute X area in square feet (H' x W'/144)
Blended refrigerants
They are physically larger
12000

21. What are the three major power-consuming devices on an air-conditioning system?
Over/under and side by side
6
Indoor fan motor - outdoor fan motor - and the compressor
15 A

22. What kind of copper tubing is used for plumbing and heating applications?
Individual return air systems and central return air systems
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Staples and tape
Nominal-sized tubing

23. What is considered normal operating conditions?
30 A
8-12 degrees F
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
400

24. If the rpm's are 3450 - how many poles does the motor have?
2
Nitrogen with a small amount of refrigerant
Suction
Shorted winding - open winding - and grounded winding

25. Where is insulation used on copper tubing used for air-conditioning?
It will be low
The suction line or the low-pressure side
45 degrees F
Negative

26. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
Positive
It also rises
45-55%
Vapor

27. On what terminal do you check amperage?
Positive
Common
Boil the liquid refrigerant out ot the oil within the crankcase
2 minutes

28. Do you need a trap on a push-through evaporator?
Side-by-side and over-and-under
No
40 degrees F
When it is a pull-through evaporator

29. How do you calculate LRA?
With an are rating
RLA/FLA x 5
Stranded
When the system is under pressure

30. At what temperature does refrigerant condense in a standard-efficiency unit?
25-ft or 50-ft
150
30-35 degrees above ambient
With 4' saddles

31. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
30 A
True
It rises
A band 4 inches or more in width

32. What is the normal evaporator temperature?
30 A
A bypass duct or a dump zone
45 degrees F
Nominal-sized tubing

33. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
45-55%
100
A bypass duct or a dump zone
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

34. What percentage silver do you need to use for an are-410 system?
Fiberglass
Vapor
15% silphos
The suction line or the low-pressure side

35. What can cause a decrease in suction pressure on an air-conditioning system?
A dirty evaporator
In parallel
40 degrees F
Inclined manometer

36. What tool is used to expand the diameter of soft copper tubing
1/4'
Individual return air systems and central return air systems
400
A swaging tool

37. How many amps can 8 g wire handle?
6
40 A
100
200

38. How many amps can 14 g wire handle?
Pull a vacuum
15 A
A dirty evaporator
A swaging tool

39. What sort of pressure will a pull-through evaporator have?
Yes
Negative
Inclined manometer
A bypass duct or a dump zone

40. At what temperature will soft solder melt?
A bypass duct or a dump zone
Below 800 degrees F
TXV
L-type

41. 10' round duct has a ballpark cfm of what?
When the system is under pressure
300
Pistons
400

42. What are the two functions of the air-conditioning system?
To remove humidity and lower dry bulb temperature
Boil the liquid refrigerant out ot the oil within the crankcase
15 A
Side-by-side and over-and-under

43. What is the difference between SEER and EER?
It rises
20 degrees above ambient
SEER includes the energy used in the start-up and shut-down cycles
A piston type metering device

44. How is the high pressure switch wired with the low pressure switch?
In parallel
Yes
Over/under and side by side
A piston type metering device

45. 10 SEER is classified as what kind of efficiency?
15 A
Infiltration and ventilation
Standard
Latent and sensible

46. Why is it necessary to have multiple refrigerant circuits in some evaporator coils?
To lower the amount of pressure drop through the coil
TXV
When it is a pull-through evaporator
Yes

47. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
When the system is under pressure
L-type
Over 800 degrees F
Latent and sensible

48. What are the components of a hard-start kit?
With 4' saddles
With an are rating
Heat loss
Potential relay and start capacitor

49. Does a package unit come from the factory pre-charged?
20 A
By increasing the surface of the condenser coil
Dehydrated with caps on each end
Yes

50. 8' round duct has a ballpark cfm of what?
Inclined manometer
SEER includes the energy used in the start-up and shut-down cycles
Staples and tape
200