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. 10 SEER is classified as what kind of efficiency?
Compressor
The takeoff fitting
Standard
Duct with insulation on the inside

2. At what temperature does refrigerant condense in a standard-efficiency unit?
Side-by-side and over-and-under
To remove humidity and lower dry bulb temperature
The suction line or the low-pressure side
30-35 degrees above ambient

3. How do you calculate LRA?
Over 800 degrees F
To lower the amount of pressure drop through the coil
Nominal-sized tubing
RLA/FLA x 5

4. What are the three major power-consuming devices on an air-conditioning system?
Before the vent
Inches of water column (in. WC)
Indoor fan motor - outdoor fan motor - and the compressor
Outside diameter (OD)

5. On what terminal do you check amperage?
A diffuser
Duct with insulation on the inside
Shorted winding - open winding - and grounded winding
Common

6. At what temperature will soft solder melt?
Dehydrated with caps on each end
12000
2 minutes
Below 800 degrees F

7. How do you calculate the area of a circle?
Pi x radius squared
Pistons
Fiberglass
20 degrees above ambient

8. If the rpm's are 1050 - how many poles does the motor have?
It will be low
High
6
A diffuser

9. The evaporator is designed to remove what two types of heat?
Latent and sensible
On the common terminal
TXV
Positive

10. What are the three pressures created by moving air in ductwork?
105 degrees F
True
Over 800 degrees F
Static pressure - velocity pressure - and total pressure

11. How many amps can 10 g wire handle?
8-12 degrees F
30 A
1/4'
25-ft or 50-ft

12. The compressor is cooled by liquid refrigerant. (True of False)
150
A bypass duct or a dump zone
False
Shorted winding - open winding - and grounded winding

13. How do you calculate ballpark superheat?
Duct - electrical - and mechanical
Subtract ambient temperature from 100
12000
Slugging

14. What is the name of the fitting where the branch line leaves the duct?
Over 800 degrees F
The takeoff fitting
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Fiberglass

15. What is considered normal operating conditions?
It will be high
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
40 A
Stranded

16. What do you use to check for leaks?
Common
Nitrogen with a small amount of refrigerant
SEER includes the energy used in the start-up and shut-down cycles
Over 800 degrees F

17. Will a dirty condenser cause a rise or fall in pressure?
It rises
Rise
18 gauge
In parallel

18. 6' round duct has a ballpark cfm of what?
100
It will have a decrease in superheat
300
A piston type metering device

19. Do you need a vent on a push-through evaporator?
45 degrees F
Yes
200
Slugging

20. What kind of refrigeratnts must be added in liquid form?
Blended refrigerants
It will have a decrease in superheat
No
A dirty evaporator

21. 10' round duct has a ballpark cfm of what?
Before the vent
400
Blended refrigerants
Negative

22. What are normal conditions - as defined by the ARI.
40 degrees F
A swaging tool
It rises
95 degrees F outside - 80 degrees F inside - and 50% relative humidity

23. Do you need a trap on a push-through evaporator?
Over/under and side by side
TXV
No
Static pressure - velocity pressure - and total pressure

24. Superheat should never be below how many degrees
Yes
Belt drive and direct drive
5 degrees
Inside diameter (ID)

25. How many amps can 8 g wire handle?
Subtract ambient temperature from 100
40 A
Potential relay and start capacitor
Inches of water column (in. WC)

26. 10 SEER is classified as what kind of efficiency?
When the system is under pressure
Standard
The suction line or the low-pressure side
A band 4 inches or more in width

27. How are the condenser coils different on a high-efficiency unit?
They are larger
By increasing the surface of the condenser coil
100 psig
SEER includes the energy used in the start-up and shut-down cycles

28. Which type of wire can handle a higher ampacity?
Sheet metal - galvanized sheet metal - fiberglass - and flexduct
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
Stranded
ACR (air-conditioning refrigeration) tubing

29. Most duct insulation is made of what?
It also rises
They are physically larger
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
Fiberglass

30. The A/C size is calculated by what?
Heat load
150
Yes
SEER includes the energy used in the start-up and shut-down cycles

31. What is lined duct?
A swaging tool
Duct with insulation on the inside
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
30 degrees F

32. If the rpm's are 750 - how many poles does the motor have?
400
20 A
Yes
8

33. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
45-55%
L-type
Positive
Fiberglass

34. Pressure in ductwork is measured In what?
It also rises
Outside of the male fitting
Inches of water column (in. WC)
Potential relay and start capacitor

35. How are the condenser coils different on a high-efficiency unit?
They are larger
20 A
40 degrees F
ACR (air-conditioning refrigeration) tubing

36. What can cause a decrease in suction pressure on an air-conditioning system?
A dirty evaporator
With a minimum of three evenly spaced self-tapping screws
Slugging
Suction

37. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
Potential relay and start capacitor
40 degrees F
True
Negative

38. Square sheet metal duct is normally fabricated in a sheet metal shop and assembled in the field. (True or False)
Suction
They are larger
Potential relay and start capacitor
True

39. How many cfm per ton?
It will have a decrease in superheat
No
Static pressure - velocity pressure - and total pressure
400

40. What are the three major power-consuming devices on an air-conditioning system?
Pi x radius squared
45 degrees F
ACR (air-conditioning refrigeration) tubing
Indoor fan motor - outdoor fan motor - and the compressor

41. Do you need a trap on a pull-through evaporator?
They are physically larger
Yes
4
When it is a pull-through evaporator

42. Where do you install a trap on a drain line?
Over/under and side by side
No
Before the vent
Pull a vacuum

43. The compressor is cooled by liquid refrigerant. (True of False)
45-55%
200
False
Positive

44. What are the components of a hard-start kit?
Potential relay and start capacitor
Individual return air systems and central return air systems
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
It will be low

45. What do you do after you braze a system?
Pull a vacuum
A swaging tool
With a minimum of three evenly spaced self-tapping screws
It will have a decrease in superheat

46. How are high-efficiency condenser coils different from standard-efficiency condenser coils?
Indoor fan motor - outdoor fan motor - and the compressor
8-12 degrees F
Average feet per minute X area in square feet (H' x W'/144)
They are physically larger

47. What is the typical pressure differance across a TXV?
100 psig
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
Vapor
Infiltration and ventilation

48. Multiple-zone systems often use what to alleviate the problem of excess air when only some zones are calling for conditioning?
To lower the amount of pressure drop through the coil
A bypass duct or a dump zone
High
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.

49. Does a package unit come from the factory pre-charged?
High
2
Yes
12000

50. A reciprocating compressor has what sort of moving parts?
Stranded
Before the vent
ACR (air-conditioning refrigeration) tubing
Pistons