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. What are the two types of return air systems in residential installations?
Individual return air systems and central return air systems
A swaging tool
20 A
Belt drive and direct drive

2. On what terminal do you check amperage?
Yes
300
Heat loss
Common

3. The fan switch opens at what temperature?
Slugging
18 gauge
Stranded
105 degrees F

4. The fan switch closes at what temperature?
4
Heat load
Pistons
140 degrees F

5. What is considered normal operating conditions?
In series
With an are rating
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
2

6. At what temperature does refrigerant condense in a standard-efficiency unit?
Potential relay and start capacitor
1/4'
30-35 degrees above ambient
No

7. 10 SEER is classified as what kind of efficiency?
45 degrees F
Heat load
It rises
Standard

8. 8' round duct has a ballpark cfm of what?
Blended refrigerants
200
Duct with insulation on the inside
Rise

9. How will too much refrigerant effect superheat?
When it is above a conditioned space
It will be low
False
Yes

10. 6' round duct has a ballpark cfm of what?
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
No
Dehydrated with caps on each end
100

11. 10' round duct has a ballpark cfm of what?
No
Suction
12000
400

12. How many amps can 14 g wire handle?
400
15 A
It will have a decrease in superheat
18 gauge

13. How are the condenser coils different on a high-efficiency unit?
Latent and sensible
Any amount
They are larger
12000

14. The refrigerant within the evaporator will typically boil at what temperature when it is 75 degrees inside with a relative humidity of 50%?
40 degrees F
TXV
With an are rating
It will have a decrease in superheat

15. What is the typical pressure differance across a TXV?
100 psig
2
ACR (air-conditioning refrigeration) tubing
300

16. When do you install a trap on a drain line?
When it is a pull-through evaporator
8-12 degrees F
Compressor
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

17. 13 SEER is classified as what kind of efficiency?
30-35 degrees above ambient
Heat loss
They are physically larger
High

18. Which type of wire can handle a higher ampacity?
RLA/FLA x 5
With an are rating
When the system is under pressure
Stranded

19. How will an overcharge affect an air-conditioning system with a fixed-orifice type metering device?
45 degrees F
When the system is under pressure
In parallel
It will have a decrease in superheat

20. How do you calculate the area of a circle?
Inches of water column (in. WC)
A piston type metering device
Infiltration and ventilation
Pi x radius squared

21. What is used to measure static air pressure in ducts.
105 degrees F
Inclined manometer
Vapor
Inches of water column (in. WC)

22. The load on the evaporater will effect which pressure?
Suction
The takeoff fitting
Belt drive and direct drive
400

23. What type of air conditioning system must be charged using the superheat method?
Btu/hr (output) / wattage (input)
A piston type metering device
A band 4 inches or more in width
TXV

24. How are the high pressure switch and the low pressure switch wired with the compressor contactor?
In series
RLA/FLA x 5
L-type
They are larger

25. What are the three pressures created by moving air in ductwork?
Outside diameter (OD)
100 psig
Potential relay and start capacitor
Static pressure - velocity pressure - and total pressure

26. At what temperature does refrigerant condense in a high-efficiency unit?
20 degrees above ambient
With an are rating
Individual return air systems and central return air systems
18 gauge

27. What kind of copper tubing is used for plumbing and heating applications?
They are physically larger
Yes
Nominal-sized tubing
Staples and tape

28. What is a package unit?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
20 degrees above ambient
Positive
A dirty evaporator

29. The crankcase heater on an air-conditioning compressor is used to what?
Pi x radius squared
Infiltration and ventilation
Btu/hr (output) / wattage (input)
Boil the liquid refrigerant out ot the oil within the crankcase

30. How do you calculate cfm?

31. How is flexible duct supported?
Pistons
A band 4 inches or more in width
Nitrogen with a small amount of refrigerant
4

32. The crankcase heater on an air-conditioning compressor is used to what?
Duct with insulation on the inside
Boil the liquid refrigerant out ot the oil within the crankcase
4
Shorted winding - open winding - and grounded winding

33. How will an overcharge affect an air-conditioning system with a fixed-orifice type metering device?
Inches of water column (in. WC)
It will have a decrease in superheat
SEER includes the energy used in the start-up and shut-down cycles
Pistons

34. What percentage silver do you use to braze two dissimilar metals such as steel and copper?
45 degrees F
45-55%
Yes
100

35. Can refrigerant line sets be altered in length?
Yes
Pi x radius squared
True
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line

36. Pressure in ductwork is measured In what?
Before the vent
A dirty evaporator
Inches of water column (in. WC)
A bypass duct or a dump zone

37. If the suction pressure rises - what happens to the head pressure?
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
It also rises
Btu/hr (output) / wattage (input)
Pi x radius squared

38. What do you use to check for leaks?
ACR (air-conditioning refrigeration) tubing
Yes
Nitrogen with a small amount of refrigerant
TXV

39. The A/C size is calculated by what?
400
Heat load
Yes
Indoor fan motor - outdoor fan motor - and the compressor

40. 13 SEER is classified as what kind of efficiency?
Rise
Staples and tape
Common
High

41. The furnace size is calculated by what?
It will be high
2
Stranded
Heat loss

42. What is the normal evaporator temperature?
2 minutes
40 degrees F
8
45 degrees F

43. How do you calculate cfm?

44. What do you use to check for leaks?
12000
20 degrees above ambient
Nitrogen with a small amount of refrigerant
Below 800 degrees F

45. Pressure in ductwork is measured In what?
Suction
Nominal-sized tubing
Static pressure - velocity pressure - and total pressure
Inches of water column (in. WC)

46. What is the name of the fitting where the branch line leaves the duct?
Shorted winding - open winding - and grounded winding
A bypass duct or a dump zone
No
The takeoff fitting

47. Does a package unit come from the factory pre-charged?
Belt drive and direct drive
Yes
Staples and tape
30 degrees F

48. How are round ducts connected to one another?
5 degrees
With a minimum of three evenly spaced self-tapping screws
20 A
False

49. What are the two functions of the air-conditioning system?
15% silphos
With a minimum of three evenly spaced self-tapping screws
Rise
To remove humidity and lower dry bulb temperature

50. A reciprocating compressor has what sort of moving parts?
TXV
Pistons
5 degrees
Static pressure - velocity pressure - and total pressure