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. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
A bypass duct or a dump zone
Latent and sensible
On the common terminal
True

2. Pressure in ductwork is measured In what?
Inches of water column (in. WC)
Over 800 degrees F
Below 800 degrees F
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity

3. Do you need a trap on a pull-through evaporator?
Below 800 degrees F
8
15 A
Yes

4. When do you install a trap on a drain line?
Indoor fan motor - outdoor fan motor - and the compressor
When it is a pull-through evaporator
Vapor
Potential relay and start capacitor

5. Superheat should never be below how many degrees
It rises
Common
5 degrees
Over/under and side by side

6. How do you calculate LRA?
Yes
Compressor
RLA/FLA x 5
Indoor fan motor - outdoor fan motor - and the compressor

7. When do you install an auxillary drain pan?
When the system is under pressure
When it is above a conditioned space
S-clips and drives (cleats)
On the common terminal

8. How do you calculate ballpark superheat?
Subtract ambient temperature from 100
In parallel
Vapor
20 A

9. What is lined duct?
With 4' saddles
Common
Duct with insulation on the inside
15% silphos

10. How are round ducts connected to one another?
150
With a minimum of three evenly spaced self-tapping screws
When the system is under pressure
15 A

11. What is the name of the fitting where the branch line leaves the duct?
6
Stranded
The takeoff fitting
A dirty evaporator

12. What is a package unit?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
1/4'
ACR (air-conditioning refrigeration) tubing
Common

13. What are the four materials used to make duct?
With an are rating
18 gauge
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
400

14. What are the components of a hard-start kit?
S-clips and drives (cleats)
Potential relay and start capacitor
Dehydrated with caps on each end
Common

15. On what terminal do you check amperage?
Nominal-sized tubing
Common
A band 4 inches or more in width
Yes

16. If the rpm's are 3450 - how many poles does the motor have?
2
Negative
20 A
In series

17. The furnace size is calculated by what?
Fiberglass
When it is above a conditioned space
Rise
Heat loss

18. The A/C size is calculated by what?
200
The suction line or the low-pressure side
Heat load
40 A

19. What is the normal evaporator temperature?
45 degrees F
Average feet per minute X area in square feet (H' x W'/144)
Common
40 degrees F

20. If the rpm's are 750 - how many poles does the motor have?
Indoor fan motor - outdoor fan motor - and the compressor
ACR (air-conditioning refrigeration) tubing
8
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

21. Why is it necessary to have multiple refrigerant circuits in some evaporator coils?
True
30 degrees F
To lower the amount of pressure drop through the coil
Standard

22. How many BTU's per ton?
When it is above a conditioned space
12000
With an are rating
200

23. Do you need a vent on a pull-through evaporator?
On the common terminal
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
40 degrees F
Yes

24. The A/C size is calculated by what?
Fiberglass
Over 800 degrees F
Heat load
In parallel

25. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
True
Over 800 degrees F
15 A
Rise

26. Will a dirty condenser cause a rise or fall in pressure?
Yes
300
Rise
20 degrees above ambient

27. Do you need a trap on a push-through evaporator?
200
Dehydrated with caps on each end
SEER includes the energy used in the start-up and shut-down cycles
No

28. The compressor is cooled by liquid refrigerant. (True of False)
Average feet per minute X area in square feet (H' x W'/144)
Pull a vacuum
False
S-clips and drives (cleats)

29. 9' round duct has a ballpark cfm of what?
300
By increasing the surface of the condenser coil
30 A
45 degrees F

30. What kind of refrigeratnts must be added in liquid form?
Static pressure - velocity pressure - and total pressure
Blended refrigerants
Pi x radius squared
Potential relay and start capacitor

31. How do you calculate EER?
Btu/hr (output) / wattage (input)
Compressor
It also rises
100 psig

32. Where do you check the amps on a motor?
On the common terminal
2
When the system is under pressure
To remove humidity and lower dry bulb temperature

33. If the rpm's are 1750 - how many poles does the motor have?
A bypass duct or a dump zone
Yes
4
A dirty evaporator

34. What sort of pressure will a pull-through evaporator have?
Negative
40 degrees F
With an are rating
Individual return air systems and central return air systems

35. How are the high pressure switch and the low pressure switch wired with the compressor contactor?
By increasing the surface of the condenser coil
Negative
In series
150

36. Where do you apply flux when soldering?
200
They are physically larger
Outside of the male fitting
Compressor

37. How is ACR tubing sized?
Outside diameter (OD)
Pistons
Subtract ambient temperature from 100
TXV

38. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
A piston type metering device
2
L-type

39. Do you need a trap on a push-through evaporator?
40 A
When the system is under pressure
No
Blended refrigerants

40. The furnace size is calculated by what?
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
Heat loss
Common
To remove humidity and lower dry bulb temperature

41. What is it called when liquid refrigerant gets into the compressor?
45-55%
Common
Slugging
140 degrees F

42. Do you need a trap on a pull-through evaporator?
18 gauge
Yes
Outside of the male fitting
Any amount

43. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
200
A dirty evaporator
L-type
With 4' saddles

44. Pressure in ductwork is measured In what?
True
Inches of water column (in. WC)
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Btu/hr (output) / wattage (input)

45. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
A swaging tool
False
30 degrees F
They are physically larger

46. How many cfm per ton?
By increasing the surface of the condenser coil
To remove humidity and lower dry bulb temperature
400
Suction

47. The compressor is cooled by liquid refrigerant. (True of False)
No
Inches of water column (in. WC)
Standard
False

48. What are the two ways that fresh air enters a structure?
Infiltration and ventilation
With 4' saddles
On the common terminal
It will have a decrease in superheat

49. How is flexible duct supported?
2 minutes
A band 4 inches or more in width
Boil the liquid refrigerant out ot the oil within the crankcase
With 4' saddles

50. 9' round duct has a ballpark cfm of what?
300
20 degrees F
A band 4 inches or more in width
100 psig