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Flashcards in Basic Hot Water Heating Systems Deck (26)
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1
Q

What is the maximum capacity of a Class 2 transformer?

A

100 VA

2
Q

What is the purpose of a reverse acting aquastat?

A

To prevent cold water from circulating in a heating system

3
Q

A boiler with standing pilot ignition will incorporate a flame rod to prove the pilot flame.

True or False

A

False

4
Q

The biggest advantage of a multi-zone system is:

a) individual zone temperature control.
b) only one circulation pump.
c) dustless heat distribution.

A

a) individual zone temperature control.

5
Q

Which is not a recommended safety and control devices for a boiler?

a) aquastat
b) flow switch
c) LWCO
d) zone valve

A

d) zone valve

6
Q

A circuit breaker can be used as a disconnect for a boiler.

True or False

A

True

7
Q

The three wire zone valve:

a) maintains its position in a power failure
b) requires a special thermostat
c) requires power to open and close the valve
d) all of the above

A

d) all of the above

8
Q

Which system utilizes a high-temperature element to ignite the main burner?

a) flame rod and ignition
b) direct spark ignition
c) hot surface ignition
d) standing pilot ignition

A

c) hot surface ignition

9
Q

An end-of-travel, or end switch, is normally open set of contacts that will close when the zone valve opens?

True or False

A

True

10
Q

Which of the following is not considered a terminal unit in a hot water heating system?

a) radiator
b) radiant panel
c) solar panel
d) plenum mounted heat exchanger

A

c) solar panel

11
Q

A gas-filled bulb/capillary tube device utilized as a temperature switch in a hot water heating system is referred to as a/an:

a) pressure relief valve
b) low water cut-out
c) end switch
d) aquastat

A

d) aquastat

12
Q

To create a spark, the ignition transformer supplies the spark igniter with typically:

a) 24V
b) 120V
c) 10kV
d) either b or c

A

c) 10kV

13
Q

Intermittent circulation boilers must use a pilot light to the main burner.

True or False

A

False

14
Q

In a single zone continuous circulation boiler system, the thermostat controls the:

a) circulation pump
b) gas valve
c) zone valve
d) all of the above

A

b) gas valve

15
Q

A light-sensitive flame proving device will:

a) experience a change in resistance when exposed to light
b) emit a small amount of light when exposed to heat
c) generate a small emf when exposed to light
d) provide the means to ignite the pilot flame

A

a) experience a change in resistance when exposed to light

16
Q

When two-wire valves are de-energized they will:

a) open
b) close
c) either a or b

A

c) either a or b

17
Q

CEC rules 26-800 to 26-808 apply only to forced air heating systems and do not apply to boilers.

True or False

A

False

18
Q

A reverse acting aquastat would be incorporated into a boiler control circuit to create a/an ___________ circulation system.

a) intermittent
b) continuous
c) cavitating
d) hydronic

A

a) intermittent

19
Q

Circulation pumps can be a single or variable speed depending on the system.

True or False

A

True

20
Q

A pressure relief valve opens when the boiler exceeds its maximum allowable working pressure.

True or False

A

True

21
Q

Seprate water flow circuits in a hot water heating system are known as:

a) circulation systems
b) multi-zone
c) radiant panels
d) zones

A

—— Come back to this, no answer in the key.

22
Q

What is the typical voltage for zone valves?

a) 10 V
b) 24 V
c) 120 V
d) 240 V

A

b) 24 V

23
Q

What is the purpose of a flame rod?

A

to detect a burner flame

24
Q

What is an LWCO used for?

A

to shut off the burner if the boiler water is too low.

25
Q

What are the two types of aquastats?

A

a) immersion

b) surface mount

26
Q

What is a device that transfers heat from one system to another called?

a) a heat transfer switch
b) a hydronic
c) a heat circulator
d) a heat exchanger

A

d) a heat exchanger