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

2. 9' round duct has a ballpark cfm of what?
A dirty evaporator
False
Yes
300

3. The fan switch opens at what temperature?
By increasing the surface of the condenser coil
Latent and sensible
Duct - electrical - and mechanical
105 degrees F

4. How many BTU's per ton?
Indoor fan motor - outdoor fan motor - and the compressor
Static pressure - velocity pressure - and total pressure
12000
Vapor

5. What is the typical pressure differance across a TXV?
100 psig
Duct - electrical - and mechanical
It will be low
Below 800 degrees F

6. What is the name of the fitting where the branch line leaves the duct?
Negative
2 minutes
The takeoff fitting
100 psig

7. Which type of wire can handle a higher ampacity?
Heat load
30 degrees F
Stranded
By increasing the surface of the condenser coil

8. Why is it necessary to have multiple refrigerant circuits in some evaporator coils?
It will be low
2
To lower the amount of pressure drop through the coil
With a minimum of three evenly spaced self-tapping screws

9. What are the components of a hard-start kit?
Pull a vacuum
Potential relay and start capacitor
The suction line or the low-pressure side
2 minutes

10. How are the high pressure switch and the low pressure switch wired with the compressor contactor?
15 A
In series
False
They are larger

11. At what temperature will brazing melt?
Inclined manometer
Individual return air systems and central return air systems
15 A
Over 800 degrees F

12. How many amps can 8 g wire handle?
Positive
Blended refrigerants
A band 4 inches or more in width
40 A

13. What are the three crafts normally associated with an air-conditioned installation?
A piston type metering device
100
Standard
Duct - electrical - and mechanical

14. What do you do after you braze a system?
20 degrees F
When it is a pull-through evaporator
Pull a vacuum
In series

15. How are the high pressure switch and the low pressure switch wired with the compressor contactor?
In series
False
Inches of water column (in. WC)
18 gauge

16. How will too much refrigerant effect subcooling?
400
It will be high
TXV
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity

17. Will a dirty condenser cause a rise or fall in pressure?
Average feet per minute X area in square feet (H' x W'/144)
Rise
High
To remove humidity and lower dry bulb temperature

18. Where is insulation used on copper tubing used for air-conditioning?
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
The suction line or the low-pressure side
Individual return air systems and central return air systems
Over 800 degrees F

19. What are the two types of package units?
Duct - electrical - and mechanical
Outside diameter (OD)
In series
Side-by-side and over-and-under

20. How do you calculate the area of a circle?
Pi x radius squared
TXV
When it is a pull-through evaporator
Infiltration and ventilation

21. How will an overcharge affect an air-conditioning system with a fixed-orifice type metering device?
It will have a decrease in superheat
A piston type metering device
The suction line or the low-pressure side
Positive

22. How long should you leave a system off once you kill power before restarting it?
A piston type metering device
Yes
2 minutes
45 degrees F

23. Do you need a vent on a pull-through evaporator?
Side-by-side and over-and-under
Shorted winding - open winding - and grounded winding
6
Yes

24. The furnace size is calculated by what?
Latent and sensible
Subtract ambient temperature from 100
A diffuser
Heat loss

25. How is ACR tubing sized?
Blended refrigerants
Outside diameter (OD)
Staples and tape
Duct with insulation on the inside

26. What is the name of the fitting where the branch line leaves the duct?
15 A
The takeoff fitting
45 degrees F
Negative

27. How do you calculate the area of a circle?
It will have a decrease in superheat
Yes
Nominal-sized tubing
Pi x radius squared

28. What are the two basic duct connection configurations for package units supply and return air ducts?
100
Below 800 degrees F
With 4' saddles
Over/under and side by side

29. What tool is used to expand the diameter of soft copper tubing
A swaging tool
Standard
Suction
1/4'

30. How is the high pressure switch wired with the low pressure switch?
Yes
Outside of the male fitting
In parallel
Rise

31. 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
40 degrees F
Yes
They are physically larger

32. What do you use to connect square and rectangular ductboard together?
Shorted winding - open winding - and grounded winding
Potential relay and start capacitor
S-clips and drives (cleats)
Duct - electrical - and mechanical

33. Where do you install a trap on a drain line?
Any amount
45 degrees F
Before the vent
400

34. On what terminal do you check amperage?
5 degrees
Common
Yes
30 A

35. In what length rolls is soft copper tubing normally available?
Duct - electrical - and mechanical
Individual return air systems and central return air systems
25-ft or 50-ft
20 degrees above ambient

36. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
Yes
L-type
To lower the amount of pressure drop through the coil
Dehydrated with caps on each end

37. What kind of copper tubing is used for plumbing and heating applications?
150
Nominal-sized tubing
False
SEER includes the energy used in the start-up and shut-down cycles

38. How is insulation around a duct rated?
Outside diameter (OD)
Compressor
With an are rating
Duct - electrical - and mechanical

39. The load on the evaporater will effect which pressure?
400
45-55%
True
Suction

40. If the rpm's are 1750 - how many poles does the motor have?
Rise
4
15% silphos
With an are rating

41. Can refrigerant line sets be altered in length?
The takeoff fitting
Yes
It will be low
1/4'

42. When must a copper joint never be soldered or brazed?
When the system is under pressure
Suction
Nominal-sized tubing
The takeoff fitting

43. How do you calculate cfm?

44. At what temperature does refrigerant condense in a high-efficiency unit?
Over/under and side by side
20 degrees above ambient
True
Inside diameter (ID)

45. What are the two basic duct connection configurations for package units supply and return air ducts?
Over/under and side by side
Positive
Heat loss
The suction line or the low-pressure side

46. A reciprocating compressor has what sort of moving parts?
Pistons
40 degrees F
When it is above a conditioned space
It will be high

47. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
Individual return air systems and central return air systems
Rise
True
Side-by-side and over-and-under

48. Which is more efficient - a TXV or a fixed-orifice metering device?
It also rises
Potential relay and start capacitor
TXV
18 gauge

49. 13 SEER is classified as what kind of efficiency?
High
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
A swaging tool
100

50. How many BTU's per ton?
45 degrees F
12000
RLA/FLA x 5
40 degrees F