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. Multiple-zone systems often use what to alleviate the problem of excess air when only some zones are calling for conditioning?
A bypass duct or a dump zone
200
S-clips and drives (cleats)
It rises

2. Where is insulation used on copper tubing used for air-conditioning?
Stranded
The suction line or the low-pressure side
Suction
Dehydrated with caps on each end

3. What are the three ways a motor can fail electrically?
Shorted winding - open winding - and grounded winding
Infiltration and ventilation
Rise
It rises

4. What are the three pressures created by moving air in ductwork?
In series
Static pressure - velocity pressure - and total pressure
It will have a decrease in superheat
30 A

5. What kind of copper tubing is used for plumbing and heating applications?
2
Nominal-sized tubing
40 degrees F
It also rises

6. Most duct insulation is made of what?
ACR (air-conditioning refrigeration) tubing
40 degrees F
Fiberglass
Compressor

7. How do you achieve high-efficiency?
4
Suction
Average feet per minute X area in square feet (H' x W'/144)
By increasing the surface of the condenser coil

8. The fan switch opens at what temperature?
Pi x radius squared
105 degrees F
Individual return air systems and central return air systems
To lower the amount of pressure drop through the coil

9. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
300
30 degrees F
Individual return air systems and central return air systems
Pistons

10. What do you use to connect square and rectangular ductboard together?
Yes
It also rises
S-clips and drives (cleats)
Duct with insulation on the inside

11. Do you need a trap on a pull-through evaporator?
Common
Yes
45-55%
105 degrees F

12. How many amps can 14 g wire handle?
Blended refrigerants
Nitrogen with a small amount of refrigerant
In series
15 A

13. How do you achieve high-efficiency?
By increasing the surface of the condenser coil
Pull a vacuum
Inclined manometer
In series

14. How do you calculate EER?
Btu/hr (output) / wattage (input)
100
A bypass duct or a dump zone
Average feet per minute X area in square feet (H' x W'/144)

15. What is the difference between SEER and EER?
Nitrogen with a small amount of refrigerant
SEER includes the energy used in the start-up and shut-down cycles
20 degrees above ambient
Indoor fan motor - outdoor fan motor - and the compressor

16. What kind of refrigeratnts must be added in liquid form?
4
Inside diameter (ID)
Blended refrigerants
Positive

17. Does a package unit come from the factory pre-charged?
40 A
Yes
True
1/4'

18. Why are some ACR tubing lines insulated?
Pistons
It will be high
S-clips and drives (cleats)
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

19. Do you need a vent on a push-through evaporator?
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
By increasing the surface of the condenser coil
Yes
25-ft or 50-ft

20. Multiple-zone systems often use what to alleviate the problem of excess air when only some zones are calling for conditioning?
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
A bypass duct or a dump zone
It also rises
Positive

21. What are the two functions of the air-conditioning system?
Belt drive and direct drive
To remove humidity and lower dry bulb temperature
Inclined manometer
Over 800 degrees F

22. How do you calculate the area of a circle?
Standard
Over 800 degrees F
Pi x radius squared
Any amount

23. The fan switch opens at what temperature?
Duct with insulation on the inside
105 degrees F
When it is a pull-through evaporator
Yes

24. How are the condenser coils different on a high-efficiency unit?
A band 4 inches or more in width
6
They are larger
Any amount

25. The furnace size is calculated by what?
Before the vent
Heat loss
High
45-55%

26. Where do you apply flux when soldering?
L-type
Outside of the male fitting
4
The takeoff fitting

27. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
Any amount
The takeoff fitting
300
Duct with insulation on the inside

28. What are the three ways a motor can fail electrically?
False
To lower the amount of pressure drop through the coil
Shorted winding - open winding - and grounded winding
45-55%

29. What sort of pressure will a pull-through evaporator have?
A band 4 inches or more in width
Heat load
Negative
A dirty evaporator

30. What component changes refrigerant from a low pressure gas to a high pressure gas?
True
Common
Stranded
Compressor

31. Do you need a trap on a push-through evaporator?
Compressor
Heat loss
No
High

32. How many amps can 12 g wire handle?
Side-by-side and over-and-under
20 A
True
15 A

33. Where do you check the amps on a motor?
It will have a decrease in superheat
With 4' saddles
On the common terminal
It rises

34. 10 SEER is classified as what kind of efficiency?
8-12 degrees F
100 psig
Standard
False

35. What are the components of a hard-start kit?
Negative
400
Potential relay and start capacitor
Any amount

36. How are round ducts supported?

37. What is the typical pressure differance across a TXV?
30 A
L-type
100 psig
No

38. At what temperature does refrigerant condense in a high-efficiency unit?
Potential relay and start capacitor
RLA/FLA x 5
20 degrees above ambient
100

39. What do you do after you braze a system?
Standard
20 A
Pull a vacuum
False

40. A reciprocating compressor has what sort of moving parts?
Pistons
Heat loss
Before the vent
Positive

41. If the rpm's are 1750 - how many poles does the motor have?
RLA/FLA x 5
4
Any amount
Infiltration and ventilation

42. What kind of copper tubing is used for plumbing and heating applications?
Below 800 degrees F
150
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Nominal-sized tubing

43. If the rpm's are 1050 - how many poles does the motor have?
SEER includes the energy used in the start-up and shut-down cycles
100 psig
20 degrees F
6

44. How do you calculate the area of a circle?
False
Yes
Pi x radius squared
Individual return air systems and central return air systems

45. What is the name of the fitting where the branch line leaves the duct?
The takeoff fitting
Yes
Outside diameter (OD)
Subtract ambient temperature from 100

46. Where do you install a trap on a drain line?
RLA/FLA x 5
A bypass duct or a dump zone
Before the vent
40 A

47. How many amps can 8 g wire handle?
20 degrees F
40 A
It will be high
200

48. Does a package unit come from the factory pre-charged?
5 degrees
Yes
L-type
A piston type metering device

49. 8' round duct has a ballpark cfm of what?
TXV
8-12 degrees F
200
Subtract ambient temperature from 100

50. 10' round duct has a ballpark cfm of what?
Yes
400
5 degrees
Static pressure - velocity pressure - and total pressure