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 will an overcharge affect an air-conditioning system with a fixed-orifice type metering device?
Outside diameter (OD)
20 degrees F
A dirty evaporator
It will have a decrease in superheat

2. Superheat should never be below how many degrees
5 degrees
SEER includes the energy used in the start-up and shut-down cycles
Before the vent
A swaging tool

3. What gauge is thermostat wire?
In series
A swaging tool
Pistons
18 gauge

4. What component changes refrigerant from a low pressure gas to a high pressure gas?
A diffuser
TXV
Compressor
Duct with insulation on the inside

5. What are the three crafts normally associated with an air-conditioned installation?
Duct - electrical - and mechanical
On the common terminal
Before the vent
Yes

6. What kind of copper tubing is used for refrigeration or air-conditioning applications?
A diffuser
When it is above a conditioned space
ACR (air-conditioning refrigeration) tubing
Over/under and side by side

7. What are the two basic duct connection configurations for package units supply and return air ducts?
Stranded
95 degrees F outside - 80 degrees F inside - and 50% relative humidity
Over/under and side by side
Individual return air systems and central return air systems

8. How does ACR copper pipe come?
Dehydrated with caps on each end
Yes
Boil the liquid refrigerant out ot the oil within the crankcase
Pi x radius squared

9. How are high-efficiency condenser coils different from standard-efficiency condenser coils?
They are physically larger
A diffuser
Yes
S-clips and drives (cleats)

10. A reciprocating compressor has what sort of moving parts?
Over/under and side by side
Pistons
45-55%
Heat load

11. What are the two types of return air systems in residential installations?
Individual return air systems and central return air systems
15% silphos
Suction
To remove humidity and lower dry bulb temperature

12. What are the two types of package units?
Btu/hr (output) / wattage (input)
Side-by-side and over-and-under
400
A bypass duct or a dump zone

13. What are the three major power-consuming devices on an air-conditioning system?
40 degrees F
Indoor fan motor - outdoor fan motor - and the compressor
Positive
A piston type metering device

14. How do you achieve high-efficiency?
18 gauge
ACR (air-conditioning refrigeration) tubing
By increasing the surface of the condenser coil
It rises

15. If the rpm's are 1750 - how many poles does the motor have?
L-type
They are larger
4
True

16. The evaporator is designed to remove what two types of heat?
2 minutes
It will have a decrease in superheat
Latent and sensible
Btu/hr (output) / wattage (input)

17. What is the typical temperature difference between a high-efficiency condenser and the ambient temperature?
Common
20 degrees above ambient
20 degrees F
Suction

18. How are round ducts connected to one another?
With 4' saddles
When the system is under pressure
With a minimum of three evenly spaced self-tapping screws
The suction line or the low-pressure side

19. What is the difference between SEER and EER?
A band 4 inches or more in width
SEER includes the energy used in the start-up and shut-down cycles
TXV
40 degrees F

20. Which type of wire can handle a higher ampacity?
SEER includes the energy used in the start-up and shut-down cycles
A swaging tool
Below 800 degrees F
Stranded

21. What do you use to check for leaks?
Below 800 degrees F
Compressor
When it is a pull-through evaporator
Nitrogen with a small amount of refrigerant

22. Which is more efficient - a TXV or a fixed-orifice metering device?
A diffuser
Outside of the male fitting
TXV
No

23. What is considered normal operating conditions?
The suction line or the low-pressure side
Dehydrated with caps on each end
Inches of water column (in. WC)
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity

24. Where do you apply flux when soldering?
The suction line or the low-pressure side
Outside of the male fitting
High
Common

25. How much superheat do you need to prevent liquid refrigerant from entering the compressor?
TXV
Any amount
L-type
105 degrees F

26. At what temperature does refrigerant condense in a high-efficiency unit?
Nitrogen with a small amount of refrigerant
RLA/FLA x 5
It will have a decrease in superheat
20 degrees above ambient

27. What kind of refrigeratnts must be added in liquid form?
Any amount
It will have a decrease in superheat
Blended refrigerants
150

28. What do you use to connect square and rectangular ductboard together?
S-clips and drives (cleats)
A bypass duct or a dump zone
Standard
It also rises

29. What are the components of a hard-start kit?
Potential relay and start capacitor
When the system is under pressure
Yes
300

30. What is the design boiling point for most evaporator coils in residential air conditioning?
20 degrees above ambient
Nominal-sized tubing
40 degrees F
Latent and sensible

31. 10' round duct has a ballpark cfm of what?
400
105 degrees F
With an are rating
4

32. What is used to measure static air pressure in ducts.
Inclined manometer
With an are rating
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
When it is above a conditioned space

33. What is the typical pressure differance across a TXV?
Potential relay and start capacitor
100 psig
Inches of water column (in. WC)
30-35 degrees above ambient

34. The A/C size is calculated by what?
Vapor
A bypass duct or a dump zone
Heat load
4

35. At what temperature does refrigerant condense in a standard-efficiency unit?
A piston type metering device
Negative
Inclined manometer
30-35 degrees above ambient

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

37. What kind of metering device do high-efficiency units usually use?
Infiltration and ventilation
TXV
40 A
Static pressure - velocity pressure - and total pressure

38. What sort of pressure will a push-through evaporator have?
20 degrees F
Positive
40 A
Heat loss

39. How many amps can 14 g wire handle?
Yes
Inside diameter (ID)
15 A
False

40. How are the high pressure switch and the low pressure switch wired with the compressor contactor?
In parallel
75 degrees F dry bulb indoor - 95 degrees F drybulb outdoor - and 50% relative humidity
In series
Outside of the male fitting

41. What is a package unit?
An air-conditioning system that has all four components (compressor - condenser - metering device - and evaporator) in one housing.
When it is a pull-through evaporator
40 A
Boil the liquid refrigerant out ot the oil within the crankcase

42. Do you need a vent on a pull-through evaporator?
When it is above a conditioned space
Standard
Yes
It will have a decrease in superheat

43. Why are some ACR tubing lines insulated?
Yes
12000
To keep refrigerant from absorbing heat and to prevent condensation from forming on the line
Compressor

44. What standard weight copper tubing is most often used in the heating and air-conditioning industry?
L-type
With an are rating
100 psig
It will be high

45. 9' round duct has a ballpark cfm of what?
300
Pull a vacuum
20 degrees above ambient
Boil the liquid refrigerant out ot the oil within the crankcase

46. How are round ducts connected to one another?
30 degrees F
Fiberglass
With a minimum of three evenly spaced self-tapping screws
To lower the amount of pressure drop through the coil

47. What can cause a decrease in suction pressure on an air-conditioning system?
Nitrogen with a small amount of refrigerant
40 degrees F
They are physically larger
A dirty evaporator

48. At what temperature will soft solder melt?
30 degrees F
Pi x radius squared
Below 800 degrees F
Over 800 degrees F

49. How are round ducts supported?

50. What is the name of the fitting where the branch line leaves the duct?
A swaging tool
The takeoff fitting
Fiberglass
30-35 degrees above ambient