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. A reciprocating compressor has what sort of moving parts?
Compressor
When the system is under pressure
Pi x radius squared
Pistons

2. At what temperature does refrigerant condense in a high-efficiency unit?
20 degrees above ambient
Compressor
To lower the amount of pressure drop through the coil
Yes

3. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
Dehydrated with caps on each end
Stranded
Any amount
100 psig

4. If the rpm's are 750 - how many poles does the motor have?
It will be high
L-type
Individual return air systems and central return air systems
8

5. What is used to measure static air pressure in ducts.
SEER includes the energy used in the start-up and shut-down cycles
Inclined manometer
True
Latent and sensible

6. On what terminal do you check amperage?
Rise
On the common terminal
Common
Duct with insulation on the inside

7. What is a package unit?
15 A
150
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Btu/hr (output) / wattage (input)

8. How are high-efficiency condenser coils different from standard-efficiency condenser coils?
In parallel
A diffuser
Infiltration and ventilation
They are physically larger

9. What are the two types of blower drives?
Staples and tape
Belt drive and direct drive
Before the vent
Average feet per minute X area in square feet (H' x W'/144)

10. The evaporator is designed to remove what two types of heat?
Latent and sensible
In series
L-type
A band 4 inches or more in width

11. How does ACR copper pipe come?
30-35 degrees above ambient
Yes
Dehydrated with caps on each end
Subtract ambient temperature from 100

12. What kind of refrigeratnts must be added in liquid form?
Blended refrigerants
100
Common
20 degrees above ambient

13. What are the three crafts normally associated with an air-conditioned installation?
8-12 degrees F
False
Duct - electrical - and mechanical
Staples and tape

14. Where do you apply flux when soldering?
No
30 A
Outside of the male fitting
Boil the liquid refrigerant out ot the oil within the crankcase

15. At what temperature does refrigerant condense in a standard-efficiency unit?
High
S-clips and drives (cleats)
The suction line or the low-pressure side
30-35 degrees above ambient

16. How are round ducts supported?

17. What are the two types of blower drives?
Side-by-side and over-and-under
Belt drive and direct drive
105 degrees F
Subtract ambient temperature from 100

18. 8' round duct has a ballpark cfm of what?
Over 800 degrees F
By increasing the surface of the condenser coil
200
Slugging

19. Which type of wire can handle a higher ampacity?
Stranded
Inside diameter (ID)
A swaging tool
Individual return air systems and central return air systems

20. What distributes supply air to a room in a structure?
Outside of the male fitting
A diffuser
Rise
Subtract ambient temperature from 100

21. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
Dehydrated with caps on each end
The takeoff fitting
They are physically larger
Any amount

22. 9' round duct has a ballpark cfm of what?
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Over/under and side by side
Infiltration and ventilation
300

23. How will too much refrigerant effect subcooling?
In parallel
It will be high
Pi x radius squared
Potential relay and start capacitor

24. If pressure rises - what happens to the superheat?
It rises
Shorted winding - open winding - and grounded winding
It will be low
Outside of the male fitting

25. Where do you install a trap on a drain line?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Potential relay and start capacitor
Suction
Before the vent

26. How will too much refrigerant effect superheat?
40 A
Negative
30-35 degrees above ambient
It will be low

27. What are the components of a hard-start kit?
Potential relay and start capacitor
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
25-ft or 50-ft
20 degrees F

28. 6' round duct has a ballpark cfm of what?
A dirty evaporator
100
They are physically larger
Stranded

29. What distributes supply air to a room in a structure?
When the system is under pressure
A diffuser
Infiltration and ventilation
Negative

30. How many amps can 12 g wire handle?
20 A
When the system is under pressure
Latent and sensible
ACR (air-conditioning refrigeration) tubing

31. If the rpm's are 3450 - how many poles does the motor have?
2
When it is above a conditioned space
TXV
45-55%

32. At what temperature will brazing melt?
Over 800 degrees F
In series
When it is above a conditioned space
Side-by-side and over-and-under

33. Most duct insulation is made of what?
2
It rises
In parallel
Fiberglass

34. How do you calculate ballpark superheat?
A piston type metering device
Slugging
Btu/hr (output) / wattage (input)
Subtract ambient temperature from 100

35. When do you install an auxillary drain pan?
4
25-ft or 50-ft
A swaging tool
When it is above a conditioned space

36. How much does a drain line need to drop per foot of length?

37. What is the design boiling point for most evaporator coils in residential air conditioning?
40 degrees F
Nitrogen with a small amount of refrigerant
150
Compressor

38. How many amps can 10 g wire handle?
18 gauge
Static pressure - velocity pressure - and total pressure
30 A
6

39. Can refrigerant line sets be altered in length?
Inclined manometer
Yes
1/4'
It also rises

40. If the rpm's are 1050 - how many poles does the motor have?
6
To lower the amount of pressure drop through the coil
Static pressure - velocity pressure - and total pressure
It will have a decrease in superheat

41. What is the normal evaporator temperature?
45 degrees F
30-35 degrees above ambient
They are physically larger
Subtract ambient temperature from 100

42. What are the three pressures created by moving air in ductwork?
Yes
8
Static pressure - velocity pressure - and total pressure
45 degrees F

43. If the rpm's are 750 - how many poles does the motor have?
2
8
Subtract ambient temperature from 100
Standard

44. The load on the evaporater will effect which pressure?
Stranded
Suction
Btu/hr (output) / wattage (input)
On the common terminal

45. The compressor is cooled by liquid refrigerant. (True of False)
400
30 degrees F
With a minimum of three evenly spaced self-tapping screws
False

46. The crankcase heater on an air-conditioning compressor is used to what?
Boil the liquid refrigerant out ot the oil within the crankcase
Side-by-side and over-and-under
They are physically larger
Vapor

47. 10' round duct has a ballpark cfm of what?
Stranded
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
400
To lower the amount of pressure drop through the coil

48. What are the two types of return air systems in residential installations?
105 degrees F
Individual return air systems and central return air systems
Suction
40 degrees F

49. At what temperature does refrigerant condense in a standard-efficiency unit?
30-35 degrees above ambient
Average feet per minute X area in square feet (H' x W'/144)
Nitrogen with a small amount of refrigerant
40 degrees F

50. Which is more efficient - a TXV or a fixed-orifice metering device?
Stranded
TXV
30 A
They are physically larger