Book 2: 1-07 - "Warm Air Furnace Components & Maintenance"

Question 1

A good rule of thumb for determining the proper tension of driving belts on blowers less than 1 kW in warm air furnaces is that for every 16 cm (6.3 in) of distance between the pulley rims, the belt should have about _____ of vertical movement when pushed vertically halfway between the pulleys.
Select one:

A. 2 cm (0.8 in)

B. 0.5 cm (0.2 in)

C. 1 cm (0.4 in)

D. 2.5 cm (1 in)

E. 1.5 cm (0.6 in)

Answer 1

C. 1 cm (0.4 in)

Question 2

From the plenum warm air flows into the _____ system which distributes the air.
Select one:

A. Plenum

B. Grille

C. Supply duct

D. Return duct

E. Register

Answer 2

C. Supply duct

Question 3

A _____ is a grille equipped with a damper to control the amount of air passing through.
Select one:

A. Fixed louvre register

B. Ceiling diffuser

C. Adjustable louvre register

D. Grille

E. Register

Answer 3

E. Register

Question 4

A _____ is a covering for any opening through which air passes.
Select one:

A. Adjustable louvre register

B. Ceiling diffuser

C. Grille

D. Register

E. Fixed louvre register

Answer 4

C. Grille

Question 5

Fans and blowers usually give little trouble if kept clean and properly lubricated:
Select one:

A. Bi-annually

B. Monthly

C. Daily

D. Yearly

E. Weekly

Answer 5

D. Yearly

Question 6

The _____ outlets should be located to prevent cold drafts from walls and windows and to maintain even temperatures in the rooms.
Select one:

A. Plenum

B. Return

C. Supply

D. Register

E. Grille

Answer 6

C. Supply

Question 7

The hot air distribution system that is ideal for buildings with a concrete slab floor and no basement is the _____ system.
Select one:

A. Perimeter loop

B. Natural circulation

C. Perimeter radial

D. Extended plenum

E. Forced circulation

Answer 7

A. Perimeter loop

Question 8

A forced warm-air furnace consists of all but which of the components listed?
Select one:

A. Filter

B. Combustion equipment

C. Dehumidifier

D. Blower or fan

E. Heat exchanger

Answer 8

C. Dehumidifier

Question 9

A _____ is a register with movable bars or louvres which allow the flow pattern of the air entering the room to be changed.
Select one:

A. Ceiling diffuser

B. Adjustable louvre register

C. Register

D. Fixed louvre register

E. Grille

Answer 9

B. Adjustable louvre register

Question 10

The centrifugal blower, or fan used in warm air furnaces are of the double inlet type with _____ vanes or blades.
Select one:

A. Backward straight

B. Backward curved

C. Forward airfoil

D. Backward airfoil

E. Forward curved

Answer 10

E. Forward curved

Question 11

With a warm air heating system if there is insufficient heat throughout the building the trouble could be:
Select one:

A. Air filters are dirty

B. Occupied and unoccupied areas receiving adequate heat

C. The thermostat is accurate

D. The bonnet temperature is at least 65°C (150°F)

E. An adequate amount of air is supplied to all rooms and to provide good air distribution

Answer 11

A. Air filters are dirty

Question 12

Most gas burners used in warm air furnaces are _____ burners.
Select one:

A. Atmospheric

B. High-pressure

C. Spud

D. Ring

E. Pressurized

Answer 12

A. Atmospheric

Question 13

With a warm air heating system if there is insufficient heat throughout the building the trouble could be:
Select one:

A. The thermostat is accurate

B. The bonnet temperature is at least 65°C (150°F)

C. Air filters are clean

D. An adequate amount of air is supplied to all rooms and to provide good air distribution

E. Unoccupied areas receiving too much heat

Answer 13

E. Unoccupied areas receiving too much heat

Question 14

A _____ is a register with fixed bars or louvres which direct the air in a specific pattern.
Select one:

A. Fixed louvre register

B. Adjustable louvre register

C. Register

D. Ceiling diffuser

E. Grille

Answer 14

A. Fixed louvre register

Question 15

With a warm air heating system if there is insufficient heat throughout the building the trouble could be:
Select one:

A. Air filters are clean

B. An adequate amount of air is supplied to all rooms and to provide good air distribution

C. The bonnet temperature is at least 65°C (150°F)

D. Occupied and unoccupied areas receiving adequate heat

E. The thermostat is inaccurate

Answer 15

E. The thermostat is inaccurate

Question 16

A _____ is a square or circular shaped facing covering the ceiling outlet. It spreads the warm air over a large area.
Select one:

A. Ceiling diffuser

B. Adjustable louvre register

C. Grille

D. Register

E. Fixed louvre register

Answer 16

A. Ceiling diffuser

Question 17

_____ are installed in branch ducts near their takeoff point on the plenum and are used to adjust the warm airflow to the various areas so that equal comfort conditions can be obtained throughout the building.
Select one:

A. Louvers

B. Dampers

C. Grilles

D. Registers

E. Plenums

Answer 17

B. Dampers

Question 18

After the temperature of the air is raised in the heat exchanger section, the warm air leaves the furnace via the:
Select one:

A. Return duct

B. Supply duct

C. Grille

D. Register

E. Plenum

Answer 18

E. Plenum

Question 19

It is common practice to use rectangular ducts for the _____ section of a duct system and circular ducts for the branch runs to the outlets.
Select one:

A. Supply

B. Return

C. Plenum

D. Register

E. Grille

Answer 19

C. Plenum

Question 20

To determine the tension in a blowers driving belt, a force of about _____ should be applied.
Select one:

A. 20 N (4.5 pounds force)

B. 75 N (17 pounds force)

C. 25 N (5.6 pounds force)

D. 45 N (10 pounds force)

E. 30 N (6.7 pounds force)

Answer 20

D. 45 N (10 pounds force)