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. 8' round duct has a ballpark cfm of what?
Stranded
40 A
200
Shorted winding - open winding - and grounded winding

2. What kind of copper tubing is used for plumbing and heating applications?
Inches of water column (in. WC)
Nominal-sized tubing
25-ft or 50-ft
105 degrees F

3. 13 SEER is classified as what kind of efficiency?
Suction
High
Nitrogen with a small amount of refrigerant
Nitrogen with a small amount of refrigerant

4. What are the two functions of the air-conditioning system?
To remove humidity and lower dry bulb temperature
S-clips and drives (cleats)
A bypass duct or a dump zone
Stranded

5. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
Btu/hr (output) / wattage (input)
Staples and tape
Before the vent
45-55%

6. How do you calculate EER?
A swaging tool
Outside diameter (OD)
Btu/hr (output) / wattage (input)
140 degrees F

7. When do you install a trap on a drain line?
It will be high
A band 4 inches or more in width
They are larger
When it is a pull-through evaporator

8. The crankcase heater on an air-conditioning compressor is used to what?
Boil the liquid refrigerant out ot the oil within the crankcase
40 degrees F
To remove humidity and lower dry bulb temperature
12000

9. The A/C size is calculated by what?
Heat load
15% silphos
True
In series

10. What sort of pressure will a pull-through evaporator have?
Over/under and side by side
Below 800 degrees F
Negative
45-55%

11. Why is it necessary to have multiple refrigerant circuits in some evaporator coils?
Inclined manometer
20 A
Negative
To lower the amount of pressure drop through the coil

12. Do you need a vent on a push-through evaporator?
Vapor
1/4'
With an are rating
Yes

13. How many amps can 14 g wire handle?
Btu/hr (output) / wattage (input)
Positive
140 degrees F
15 A

14. The refrigerant within the evaporator will typically boil at what temperature when it is 75 degrees inside with a relative humidity of 50%?
100 psig
A bypass duct or a dump zone
40 degrees F
Heat load

15. At what temperature will soft solder melt?
45-55%
Below 800 degrees F
15 A
A diffuser

16. How many amps can 8 g wire handle?
With an are rating
40 A
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
Btu/hr (output) / wattage (input)

17. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
105 degrees F
Over 800 degrees F
30 degrees F
Inclined manometer

18. Pressure in ductwork is measured In what?
6
Inches of water column (in. WC)
S-clips and drives (cleats)
It will be low

19. What kind of metering device do high-efficiency units usually use?
Potential relay and start capacitor
Pull a vacuum
Over/under and side by side
TXV

20. The load on the evaporater will effect which pressure?
Suction
Vapor
TXV
Inclined manometer

21. When must a copper joint never be soldered or brazed?
Inside diameter (ID)
When the system is under pressure
Indoor fan motor - outdoor fan motor - and the compressor
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

22. What kind of copper tubing is used for refrigeration or air-conditioning applications?
The suction line or the low-pressure side
150
Inches of water column (in. WC)
ACR (air-conditioning refrigeration) tubing

23. The compressor is cooled by liquid refrigerant. (True of False)
High
Blended refrigerants
45 degrees F
False

24. What sort of pressure will a pull-through evaporator have?
Blended refrigerants
Negative
It rises
5 degrees

25. What is the name of the fitting where the branch line leaves the duct?
Stranded
40 degrees F
SEER includes the energy used in the start-up and shut-down cycles
The takeoff fitting

26. What do you do after you braze a system?
30 degrees F
Static pressure - velocity pressure - and total pressure
Pull a vacuum
Yes

27. How many cfm per ton?
It will have a decrease in superheat
Nominal-sized tubing
400
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

28. 10' round duct has a ballpark cfm of what?
Over/under and side by side
High
400
Standard

29. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
Any amount
150
45-55%
2 minutes

30. Will a dirty condenser cause a rise or fall in pressure?
Heat load
Yes
Rise
Latent and sensible

31. What distributes supply air to a room in a structure?
Outside diameter (OD)
Suction
L-type
A diffuser

32. How will an overcharge affect an air-conditioning system with a fixed-orifice type metering device?
Inside diameter (ID)
S-clips and drives (cleats)
When it is above a conditioned space
It will have a decrease in superheat

33. Why are some ACR tubing lines insulated?
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
25-ft or 50-ft
5 degrees
In parallel

34. 10 SEER is classified as what kind of efficiency?
25-ft or 50-ft
400
Standard
Nitrogen with a small amount of refrigerant

35. What distributes supply air to a room in a structure?
Over 800 degrees F
A diffuser
L-type
40 A

36. How do you calculate the area of a circle?
Stranded
On the common terminal
Pi x radius squared
With an are rating

37. Can refrigerant line sets be altered in length?
Stranded
No
Yes
40 degrees F

38. What is the range for normal superheat and subcooling?
12000
On the common terminal
8-12 degrees F
40 A

39. The crankcase heater on an air-conditioning compressor is used to what?
30 A
Inclined manometer
Staples and tape
Boil the liquid refrigerant out ot the oil within the crankcase

40. What kind of refrigeratnts must be added in liquid form?
Latent and sensible
Btu/hr (output) / wattage (input)
Blended refrigerants
Staples and tape

41. If the rpm's are 1750 - how many poles does the motor have?
4
150
200
Btu/hr (output) / wattage (input)

42. Do you need a trap on a push-through evaporator?
No
It also rises
Duct with insulation on the inside
Negative

43. Where do you apply flux when soldering?
40 degrees F
Outside of the male fitting
Over/under and side by side
With a minimum of three evenly spaced self-tapping screws

44. 6' round duct has a ballpark cfm of what?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Dehydrated with caps on each end
100

45. What sort of pressure will a push-through evaporator have?
8
Positive
It will be high
False

46. What gauge is thermostat wire?
Average feet per minute X area in square feet (H' x W'/144)
18 gauge
5 degrees
Potential relay and start capacitor

47. What tool is used to expand the diameter of soft copper tubing
45 degrees F
A bypass duct or a dump zone
A swaging tool
Yes

48. What are the three major power-consuming devices on an air-conditioning system?
300
Indoor fan motor - outdoor fan motor - and the compressor
TXV
Shorted winding - open winding - and grounded winding

49. Does a package unit come from the factory pre-charged?
High
Yes
Outside of the male fitting
Boil the liquid refrigerant out ot the oil within the crankcase

50. What are the three major power-consuming devices on an air-conditioning system?
6
Indoor fan motor - outdoor fan motor - and the compressor
Outside of the male fitting
Common