Electrical

Question 1

During a power outage a thermopile/powerpile equipped burner in a convection type appliance (space or wall heater) will…

Answer 1

Continue to operate normally

Question 2

*An open circuit test for a thermocouple should read

Answer 2

A maximum of 30 mvdc and a minimum of 20 mvdc

Question 3

Minimum operating voltage of a thermocouple before replacing it is…

Answer 3

8 mvdc

Question 4

A reading of 10-15mvdc across a closed switch on a powerpile system may indicate…

Answer 4

Switch contact is in poor condition

Question 5

A millivolt system, using 16 gauge wire can have a maximum length of…

Answer 5

50 feet

Question 6

Drop out reading of 10 millivolts or more indicates…

Answer 6

Defective pilot stat in gas valve

Question 7

Thermocouple tip should be inserted into the pilot flame…

Answer 7

3/8 - 1/2 inch

Question 8

Noisy or lifting pilot flame indicates

Answer 8

High gas pressure

Question 9

Millivolt wiring can’t run near line voltage wiring since…

Answer 9

Line voltage wiring will induce a voltage into millivolt wiring

Question 10

A thermostat for millivolt systems is rated in

Answer 10

0-1.5 VDC

Question 11

3 voltage outputs for a thermopile/powerpile

Answer 11

250, 500, 750 MV

Question 12

Transformers power output(s)

Answer 12

VA and Watts

Question 13

What does a transformer consist of?

Answer 13

Core of iron plates, primary and secondary winding

Question 14

Best type of connection for millivolt systems

Answer 14

Soldered connections

Question 15

Motor starting switch rated in…

Answer 15

Horsepower

Question 16

Temperature difference needed between hot and cold junction

Answer 16

400 Farenheit

Question 17

Pilot stat test operation depends on two tests

Answer 17

5 to 2 mvdc, 90 seconds

Question 18

Another thing to do

Answer 18

Go over reading diagrams

Question 19

Electrical service is rated in

Answer 19

Amps

Question 20

Minimum electrical service to a new residential building

Answer 20

100 Amps

Question 21

Electrical distribution system consists of:

Answer 21

Electric meter, main disconnect, distribution panel

Question 22

What protection does a 240 volt circuit need in the distribution panel?

Answer 22

Double pole breaker

Question 23

Overload protection for a 120 volt circuit in the distribution panel

Answer 23

Single pole breaker

Question 24

GFI is required in…

Answer 24

Wet locations

Question 25

When is gas piping bonded?

Answer 25

To prevent arcing or sparks

Question 26

Ultimate purpose of a fuse or circuit breaker in the distribution system

Answer 26

To protect higher amperage from damaging electrical conductors

Question 27

Circuits powering a motor that is protected by a plug fuse, shall use a

Answer 27

Type P

Question 28

Electrical conductors are made in

Answer 28

Solid, stranded wire

Question 29

*Allowable amperage in a circuit using No.14/3 AWG Wire at 60 Degrees Celsius

Answer 29

20 Amps

Question 30

NMD stands for...

Answer 30

Non-metallic dry

Question 31

NMW stands for...

Answer 31

Non-metallic wet

Question 32

Maximum allowable amperage using #10 AWG wire

Answer 32

30 Amps

Question 33

White wire indicates

Answer 33

Neutral conductor

Question 34

Wire exposed to mechanical damage must be

Answer 34

AC (BX)

Question 35

The lower the gauge wire

Answer 35

The more current the conductor can safely carry

Question 36

Types of wiring diagrams in the gas industry

Answer 36

Pictoral, schematic, connection

Question 37

Where does the circuit breaker in a 120v circuit supply power from?

Answer 37

Load side of the main breaker

Question 38

Maximum amperage of a fuse in a distribution panel is limited by

Answer 38

Gauge of the wire

Question 39

Armoured cable is

Answer 39

BX

Question 40

Motor circuit protection fuse is a

Answer 40

Time delay fuse

Question 41

Where does the 240v supply for an electric range come from last

Answer 41

Load side of a double branch breaker

Question 42

Schematic diagrams show components

Answer 42

Normally de-energized

Question 43

Direct current travels

Answer 43

In one direction forward

Question 44

Line and load sides for the disconnect/service switch use what colour for residential furnaces

Answer 44

Both black wires

Question 45

Electrical conductors when subjected to higher temperatures

Answer 45

Results in lower resistance

Question 46

Unit of measure for EMF

Answer 46

Volts

Question 47

Fuses and breakers protect

Answer 47

Wires

Question 48

Max amps for 12 AWG

Answer 48

20 Amps

Question 49

Diameter of wire goes up

Answer 49

Resistance goes down

Question 50

Voltage measured in residential distribution system

Answer 50

240v

Question 51

3 operating controls

Answer 51

Thermostat, operating aquastat, operating pressure controls

Question 52

3 safety controls

Answer 52

High-limit switch, pressure switch, flow switch

Question 53

3 types of pilots in a residential furnace

Answer 53

Standing, intermittent, hot surface igniter

Question 54

3 main types of automatic ignition control systems in a residential furnace

Answer 54

Intermittent pilot, direct spark ignition, hot surface ignition

Question 55

3 main components in a combination gas valve

Answer 55

Gas control valve, pressure regulator, pilot

Question 56

Another name for an air flow switch

Answer 56

Sale switch

Question 57

Minimum ratio of ground surface area to flame rod surface area for proper flame rectification

Answer 57

4-1

Question 58

Advantage of a redundant gas valve

Answer 58

Higher safety (second shut-off valve is incorporated) Eliminates the

Question 59

Safety device used on all storage type water heaters

Answer 59

Temperature and pressure relief valve

Question 60

3 types of gas pressure regulators

Answer 60

Line pressure regulator, appliance regulator, service regulator

Question 61

Sequence of operation for CAT 1 Fan Assist Furnace with D.C

Answer 61

Call for Heat, inducer Motor Start, Pressure Switch Check, Ignition Sequence, Flame Sensing, Main Burner Operation, Blower Motor Activation, Thermostat Satisfaction

Question 62

Basic operation of ignition system

Answer 62

Perform safety check, ignite the flame, powering gas valve, proving flame, monitor flame

Question 63

SRC, TRIAC, and DIAC are

Answer 63

Thyristors

Question 64

Primary difference between a relay and contactor

Answer 64

Relay for lower power application, contactor for higher power applications

Question 65

Relay operates by

Answer 65

Electromagnetic coil

Question 66

Thermocouple MV range

Answer 66

0-30

Question 67

Millivolt - Volt

Answer 67

1/1000

Question 68

Thermopile MV range

Answer 68

Up to 750 mv

Question 69

Open circuit thermocouple test

Answer 69

Should read 30 mv, below 20 mv must be replaced

Question 70

Closed circuit thermocouple test

Answer 70

Should read 15 mv, below 8 mv must be replaced

Question 71

Pilotstat coil MV reading

Answer 71

Under normal operation 10-15 mv, must hold the valve open until 5-2 mv

Question 72

750 mv thermopile must power...

Answer 72

Control circuit and combustion safety circuit in parallel

Question 73

30 ft = AWG

Answer 73

18 Min.

Question 74

50 ft = AWG

Answer 74

16 min.

Question 75

80 ft = AWG

Answer 75

14 min.

Question 76

Thermopile = How many thermocouples

Answer 76

10-30

Question 77

Thermocouples = Which pilot?

Answer 77

Standing

Question 78

Type of current for thermocouples

Answer 78

DC

Question 79

Thermostat: R= 24v power W= Heating Y= Cooling G= Fan C = 24v Common

Answer 79

YEaaaaaa

Question 80

Where would you find an operating pressuretrol?

Answer 80

Hot water boiler

Question 81

Operating pressuretrol responds to changes in

Answer 81

Steam pressure

Question 82

Heat anticipator is wired

Answer 82

In series w the gas valve

Question 83

HIgh gas pressure switch opens when pressure is exceeded by

Answer 83

25%

Question 84

When heated, ignites burners in a furnace

Answer 84

Hot surface igniter

Question 85

Unitrol is used on

Answer 85

Water heater

Question 86

Flame rod is made of

Answer 86

Kanthol

Question 87

Valve for throttling fluid

Answer 87

Globe valve

Question 88

Redundant gas valve contains

Answer 88

2 automatic gas shut off valves in series

Question 89

Rod and tube is made of

Answer 89

Invar