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. Pressure in ductwork is measured In what?
2
Fiberglass
With a minimum of three evenly spaced self-tapping screws
Inches of water column (in. WC)

2. Will a dirty condenser cause a rise or fall in pressure?
Duct - electrical - and mechanical
SEER includes the energy used in the start-up and shut-down cycles
Rise
A piston type metering device

3. If the rpm's are 1750 - how many poles does the motor have?
Fiberglass
TXV
Rise
4

4. What sort of pressure will a push-through evaporator have?
Positive
400
Nominal-sized tubing
With 4' saddles

5. What is used to measure static air pressure in ducts.
They are physically larger
140 degrees F
Inclined manometer
Nominal-sized tubing

6. What percentage silver do you need to use for an are-410 system?
400
15% silphos
6
8

7. What kind of refrigeratnts must be added in liquid form?
Blended refrigerants
18 gauge
When the system is under pressure
20 degrees F

8. When do you install an auxillary drain pan?
When it is above a conditioned space
Yes
It rises
In series

9. How is the high pressure switch wired with the low pressure switch?
It also rises
In parallel
Fiberglass
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

10. 9' round duct has a ballpark cfm of what?
300
40 degrees F
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
400

11. Do you need a vent on a push-through evaporator?
TXV
Yes
When it is a pull-through evaporator
Standard

12. How are round ducts connected to one another?
ACR (air-conditioning refrigeration) tubing
It will have a decrease in superheat
With a minimum of three evenly spaced self-tapping screws
140 degrees F

13. What distributes supply air to a room in a structure?
ACR (air-conditioning refrigeration) tubing
12000
A diffuser
No

14. What is the difference between SEER and EER?
Infiltration and ventilation
It will have a decrease in superheat
20 degrees above ambient
SEER includes the energy used in the start-up and shut-down cycles

15. 13 SEER is classified as what kind of efficiency?
High
A swaging tool
Individual return air systems and central return air systems
Yes

16. What do you use to connect square and rectangular ductboard together?
40 degrees F
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
S-clips and drives (cleats)
20 A

17. In what state is the refrigerant in the compressor?
Staples and tape
Vapor
2 minutes
Duct with insulation on the inside

18. What is the typical pressure differance across a TXV?
12000
Below 800 degrees F
8-12 degrees F
100 psig

19. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
Dehydrated with caps on each end
Belt drive and direct drive
Yes
Any amount

20. What are the two ways that fresh air enters a structure?
Nominal-sized tubing
Infiltration and ventilation
Heat loss
200

21. Which type of wire can handle a higher ampacity?
When the system is under pressure
Stranded
Pistons
Over/under and side by side

22. Sections of duct board can be fastened together with what?
They are larger
It will be high
Staples and tape
Average feet per minute X area in square feet (H' x W'/144)

23. How will too much refrigerant effect superheat?
It will be low
S-clips and drives (cleats)
With an are rating
Compressor

24. The A/C size is calculated by what?
4
It will have a decrease in superheat
Heat load
Nominal-sized tubing

25. 10 SEER is classified as what kind of efficiency?
300
Standard
4
40 A

26. What is a package unit?
Heat loss
Inclined manometer
Infiltration and ventilation
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

27. How will too much refrigerant effect superheat?
It will be low
It rises
Individual return air systems and central return air systems
It also rises

28. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
2
45-55%
To lower the amount of pressure drop through the coil
To lower the amount of pressure drop through the coil

29. What are normal conditions - as defined by the ARI.
30-35 degrees above ambient
20 degrees above ambient
In parallel
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

30. How many amps can 10 g wire handle?
A bypass duct or a dump zone
In parallel
30 A
Side-by-side and over-and-under

31. What is the typical temperature difference between a standard-efficiency condenser and the ambient temperature?
30 degrees F
40 A
Positive
Static pressure - velocity pressure - and total pressure

32. The furnace size is calculated by what?
In parallel
True
8
Heat loss

33. What is used to measure static air pressure in ducts.
False
Inclined manometer
Infiltration and ventilation
Slugging

34. 10' round duct has a ballpark cfm of what?
40 degrees F
Inside diameter (ID)
400
Static pressure - velocity pressure - and total pressure

35. Do you need a vent on a push-through evaporator?
Yes
8-12 degrees F
Slugging
Yes

36. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
When it is a pull-through evaporator
Duct with insulation on the inside
True
30-35 degrees above ambient

37. How will an overcharge affect an air-conditioning system with a fixed-orifice type metering device?
It will have a decrease in superheat
Btu/hr (output) / wattage (input)
12000
1/4'

38. What sort of pressure will a pull-through evaporator have?
Yes
Negative
A dirty evaporator
Inside diameter (ID)

39. Do you need a trap on a push-through evaporator?
Over 800 degrees F
It will be high
No
A diffuser

40. When do you install a trap on a drain line?
Nominal-sized tubing
It rises
When it is a pull-through evaporator
It will be high

41. How do you calculate ballpark superheat?
Subtract ambient temperature from 100
ACR (air-conditioning refrigeration) tubing
Pi x radius squared
Pistons

42. How are the condenser coils different on a high-efficiency unit?
TXV
They are larger
2
The takeoff fitting

43. Do you need a trap on a pull-through evaporator?
Yes
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
S-clips and drives (cleats)
ACR (air-conditioning refrigeration) tubing

44. Where do you apply flux when soldering?
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
High
Outside of the male fitting
4

45. Which is more efficient - a TXV or a fixed-orifice metering device?
Inclined manometer
TXV
True
Rise

46. What are the four materials used to make duct?
Btu/hr (output) / wattage (input)
Pistons
Shorted winding - open winding - and grounded winding
Sheet metal - galvanized sheet metal - fiberglass - and flexduct

47. The refrigerant within the evaporator will typically boil at what temperature when it is 75 degrees inside with a relative humidity of 50%?
With an are rating
40 degrees F
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
L-type

48. 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
12000
High
Over 800 degrees F

49. The fan switch opens at what temperature?
40 degrees F
105 degrees F
Positive
A band 4 inches or more in width

50. Can refrigerant line sets be altered in length?
Individual return air systems and central return air systems
Yes
300
15% silphos