Rvia Appliance Practice Test

Front 1

When servicing a water heater, propane flow downstream of the solenoid valve is determined by

Back 1

installing a monometer at the pressure tap.

Front 2

Which of his five senses will a technician use to find and verify a leaking propane fitting?

Back 2

Sight

Front 3

Which test instrument can be used to determine that a gas solenoid is functioning?

Back 3

Ohmmeter

Front 4

11 inches water column is the

Back 4

pressure coming from the second stage of a propane regulator

Front 5

What percentage of propane flow is required when setting the system operating pressure (adjusting regulator)?

Back 5

50%

Front 6

Which two methods are used to determine if a leak in the propane system exists? 1) Timed Pressure Drop 2) Leak Detector Solution 3) Regulator Lockup Test 4) Bubble Leak Tester

Back 6

1 and 4

Front 7

Which two methods are used to locate a leak in the propane system? 1) Electronic Leak Detector 2) Leak Detector Solution 3) Pressure-drop Test 4) Hearing (hissing sound)

Back 7

1 and 2

Front 8

It is required that you change the fill valve on a mounted ASME tank. To safely remove propane from the tank you will

Back 8

burn off the propane with a suitable torch.

Front 9

An opened outage valve is used

Back 9

to indicate the maximum liquid level.

Front 10

Backup wrenches are used

Back 10

to prevent damage to propane connections.

Front 11

What propane system fault condition may be present at an appliance in a retracted slideout, yet not seen when the room is extended?

Back 11

Low or no gas pressure.

Front 12

Automatic changeover regulators are found on

Back 12

dual DOT cylinders

Front 13

Regarding regulator lockup, which of the following statements is false?

Back 13

A timed pressure drop test must be preformed after setting the lockup pressure

Front 14

The air conditioner is a 120 VAC, 60 Hz appliance. The proper operation range is

Back 14

between ±10% (103.5 and 132 VAC)

Front 15

To measure the total amperage drawn by an RV air conditioner you would attach an ammeter to

Back 15

the A/C junction box

Front 16

The evaporator in an RV air conditioner

Back 16

releases heat into the atmosphere

Front 17

The rotary switch on a manually controlled air conditioner

Back 17

controls the thermostat

Front 18

Before testing for an open or shorted capacitor, with an ohmmeter you must first

Back 18

discharge the capacitor using a ammeter

Front 19

A measurement taken by clamping a test meter around the run (R) or common (C) compressor lead will indicate

Back 19

the running amperage

Front 20

High side and low side are two types of restrictions found in the sealed refrigerant system. The basic criteria to use in determining a restriction is (are)

Back 20

amp draw and pressure

Front 21

Used in evaluating air conditioner performance, the delta-temperature relationship is the temperature change between the

Back 21

air entering and leaving the evaporator coil

Front 22

Normal delta temperature is approximately 20 degrees Fahrenheit. An increase in ____ will decrease the delta temperature.

Back 22

humidity

Front 23

The pressure of the refrigerant _____ as the ambient air temperature _____ .

Back 23

increases / increases

Front 24

The water dripping on the roof of an RV from an A/C unit has been removed from the

Back 24

moisture inside the RV

Front 25

Improper or insufficient air flow through the coils of the evaporator and condenser is the second most common reason why air conditioners stop cooling. What is the main reason?

Back 25

Electrical problem

Front 26

Liquid refrigerant is vaporized by the absorption of heat and moisture from inside the coach in what component?

Back 26

Evaporator

Front 27

The high temperature overload switch is directly affected by the current draw at the compressor and also the temperature of the

Back 27

windings

Front 28

To safely discharge a run capacitor, attach the leads of a VOM set to the

Back 28

highest AC scale

Front 29

A typical heat strip attachment in working condition will measure about how many Ohms?

Back 29

9.5

Front 30

The lowest safe operating line voltage for a roof A/C is

Back 30

103 VAC

Front 31

When installing a roof A/C, it is approximately 21-feet from the mounting location to the breaker box. What size Romex is required?

Back 31

12-gauge

Front 32

When mounting a wall thermostat be sure it is installed on an inside wall

Back 32

about five feet above the floor

Front 33

12-VDC is used within a 120-VAC RV air conditioner system

Back 33

Both A and B

Front 34

The first step in troubleshooting an A/C system that does not work at all is to

Back 34

verify the incoming 120-VAC

Front 35

BTU stands for

Back 35

British Thermal Unit

Front 36

Refrigerant changes from liquid to low pressure vapor at the

Back 36

evaporator coil

Front 37

Refrigerant changes from a low pressure vapor to a high pressure vapor at the

Back 37

Compressor

Front 38

Refrigerant changes from a high pressure vapor to a high pressure liquid at the

Back 38

condenser coil

Front 39

In an air conditioner unit, the component in which the heat is absorbed from the living area is

Back 39

evaporator coil

Front 40

The main difference between the heating and cooling modes of a heat pump is

Back 40

the flow of the refrigerant is reversed

Front 41

What are the four selector switches used in the manufacture of RV air conditioners?

Back 41

10, 8, 6, and 5 position

Front 42

You are checking the compressor. When the outside or inside ambient temperature rises, the load conditions change and amperage

Back 42

increases

Front 43

The 12 VDC operating range for a Dometic air conditioner is

Back 43

9 to 16

Front 44

For Dometic air conditioner normal operation, AC voltage needs to stay within a range of

Back 44

103.5 - 126.5

Front 45

Insufficient millivolt output from the thermocouple may be caused by all of the following except

Back 45

low battery voltage

Front 46

When installing a thermocouple do not over tighten, this is a(n) ____ connection

Back 46

electrical

Front 47

A fitting on a water heater control valve is provided for a(an)

Back 47

propane pressure test port

Front 48

On a D.S.I water heater the thermostat is located on

Back 48

the outside of the tank

Front 49

The initials E.C.O. on a D.S.I. water heater stand for

Back 49

Energy Cutoff Switch

Front 50

A D.S.I. circuit board controls what function?

Back 50

Sending spark to the electrode while powering the propane valve

Front 51

What material is used in the construction of an Atwood water heater tank?

Back 51

Aluminum

Front 52

To bench test an electric thermostat, attach the leads of your VOM to the contacts of the thermostat and test for

Back 52

continuity

Front 53

An accepted method for testing an electric water heater element is to

Back 53

perform a resistance test

Front 54

What is the maximum size heating element that can be used on a 15 amp circuit and still meet the NEC (electrical code)?

Back 54

1,400 watts

Front 55

An open Energy Cutoff will

Back 55

shutdown the water heater completely

Front 56

A defective electric heating element would be indicated by

Back 56

Voltage at the terminals but no amperage draw

Front 57

On a pilot model water heater which component does not affect the flow of propane when attempting to light the pilot light?

Back 57

Thermocouple

Front 58

Which component does not affect the electrode sparking on a DSI water heater?

Back 58

Gas valve coil

Front 59

Temperature and pressure (T&P) relief valve weeping

Back 59

is a natural event

Front 60

Excessive sooting in the combustion chamber of water heater can be caused by

Back 60

misaligned burner

Front 61

A water heater bypass valve that is incorrectly set can cause

Back 61

variations in water temperature at the faucet

Front 62

A component that protects the water heater tank from corrosion is called a(an)

Back 62

anode

Front 63

Another way to check the heating element is to check resistance. After the power has been turned off and the wires disconnected from the heating element, you can check the resistance. The water heater is a 120 VAC, 1000-watt heater. What is the correct resistance?

Back 63

14.46 ohms

Front 64

The pilot model water heater must be supplied with _____ inches nominal water column of propane in order to work

Back 64

11

Front 65

D.S.I. stands for

Back 65

Direct Spark Ignition

Front 66

The thermal cut-off device

Back 66

opens the electrical circuit

Front 67

The same customer has returned three times with the same problem. Each time you replaced the circuit board and the D.S.I. water heater works for a short time. What is probably happening?

Back 67

An outside influence is destroying the boards

Front 68

Propane valve coils need a minimum of _____ volts to open

Back 68

10.5

Front 69

When checking propane valve coils for resistance, a good coil should have a resistance of _____ ohms.

Back 69

30 – 50

Front 70

The process of removing sediment from the bottom of a water tank is called

Back 70

flushing

Front 71

Weeping or dripping of the P&T relief valve while the water heater is operating usually means

Back 71

the air pocket in the water tank needs to be restored

Front 72

Replace the anode

Back 72

when it has been reduced in size by 25%

Front 73

Atwood's newer adjustable DSI thermostat control allows temperature settings between

Back 73

None of the above ; 90 - 140 degrees F; 100 - 150 degrees F; 110 - 160 degrees F

Front 74

All 120 VAC heating elements for RV water heaters are rated between

Back 74

1000 - 1500 watts

Front 75

Electric heating element: 1500-watts. Incoming voltage: 120 VAC. What would be the resistance measurement of a good, working element?

Back 75

9.6 ohms

Front 76

On a water heater with an adjustable main burner assembly, the preliminary setting of the air shutter should be

Back 76

1/4 open position

Front 77

On a DSI water heater the E.C.O. is typically set to

Back 77

180 degrees F

Front 78

When its rating is exceeded, the ECO on a DSI unit will immediately shut down the

Back 78

gas valve

Front 79

The resistance measurement of the coil portion of a good DSI gas valve should read between

Back 79

30 to 50 ohms

Front 80

On DSI models with three probes at the igniter, one probe is for the spark, one for the sense circuit and one for the

Back 80

ground

Front 81

For proper operation, the minimum supply voltage coming into an Atwood DSI model is

Back 81

10.5 VDC

Front 82

To minimize P&T valve weeping, replenish the internal air pocket inside the tank. Which step below is not a part of that process?

Back 82

Turn on the water heater

Front 83

Which of the following is not a function of the PC board

Back 83

Produces the micro-amps for the flame sense circuit

Front 84

To remedy a lockout condition on a DSI water heater

Back 84

turn off the power switch, then turn it back on

Front 85

The main burner orifice size and combustion air volume of a furnace determines the

Back 85

BTU rating

Front 86

What event causes the blower motor to begin operating?

Back 86

Thermostat calls for heat

Front 87

Residual gases in the combustion chamber are removed before the burner ignites by

Back 87

running the blower motor

Front 88

A millivolt meter is used to test a

Back 88

thermocouple

Front 89

A ohmmeter is used to test a

Back 89

thermostat

Front 90

The component that moves fresh air into the combustion chamber is the

Back 90

combustion air wheel

Front 91

An increase in blower speed and decrease in blower motor amp draw is caused by

Back 91

air cavitation caused by blocked ducts

Front 92

Which component is not in the propane delivery system of a D.S.I. furnace?

Back 92

Gas cock

Front 93

Primary and secondary air refer to

Back 93

air mixed with gas and air use for combustion

Front 94

Which component prevents furnace ignition if there is insufficient air to purge the combustion chamber?

Back 94

Sail switch

Front 95

A high temperature safety device on a furnace is the

Back 95

Limit switch

Front 96

Which will not affect the operation of the sail switch

Back 96

gas control assembly

Front 97

Obstructions in the furnace air vent tubes will create

Back 97

a restriction in the flow of secondary air

Front 98

When voltage is supplied to the DSI circuit board, there is a(an) _____ before ignition.

Back 98

approximate 20 second delay

Front 99

The coolant level in a hydronic heating system is checked by

Back 99

visual inspection of the expansion tank

Front 100

The flame sense function on a DSI furnace equipped with a remote sense circuit senses the flame via a separate electrode. On a furnace equipped with a local sense circuit, the flame is actually monitored and sensed via

Back 100

the ground electrode

Front 101

In any forced air furnace, the resulting products of proper combustion are never mixed with air inside the RV because

Back 101

of the design of the sealed combustion chamber coupled with the flow of air through a heat exchanger

Front 102

With a proper heat anticipator setting, the furnace should cycle how many times per hour on average once the system has operated for a few hours?

Back 102

5 - 6 times

Front 103

Another name for a thermopile is

Back 103

pilot generator

Front 104

A sail switch is also called a(n)

Back 104

air prover

Front 105

The power source used for the typical modulating gas valve includes

Back 105

Neither A or B

Front 106

The two types of thermostats used in RV heating systems are

Back 106

wall and modulating valve

Front 107

The device which controls the furnace operation by reacting to room temperature and opening and closing a set of contact points which allows current to flow to the control valve is the

Back 107

thermostat

Front 108

The typical furnace pilot assembly consists of the pilot burner and

Back 108

pilot orifice

Front 109

When troubleshooting a pilot model furnace, if the gas valve does not open and the required voltage is present at the valve contacts,

Back 109

replace the gas valve

Front 110

If the pilot flame will not stay lit when releasing the manual pilot valve,

Back 110

verify the output of the thermocouple

Front 111

To test a thermostat on a gravity heater, simply measure for the correct

Back 111

continuity

Front 112

What type of furnace functions by having the blower engaged prior to the burner lighting?

Back 112

Forced air

Front 113

The purpose for having the blower start before lighting the burner is to

Back 113

purge the combustion chamber of any residual gases

Front 114

A furnace "cycling on limit" may have a

Back 114

restricted return air path; crushed delivery duct; faulty limit switch

Front 115

TDR stands for

Back 115

Time Delay Relay

Front 116

On a pilot model furnace equipped with a piezo ignition system, the gap between the electrode and burner should be

Back 116

3/16-inch

Front 117

On a forced air furnace, as the thermostat senses the interior air temperature, the contacts will open removing power from the gas valve. The blower motor will still continue to run until which device cools enough to stop the current flow to the motor?

Back 117

TDR

Front 118

Since the fan relay circuit is a normally "open" circuit, there should always be voltage from the furnace circuit breaker to the

Back 118

fan relay terminal

Front 119

On a pilot model forced air furnace, which of the following is NOT a cause for the symptom… blower runs but fails to ignite burner?

Back 119

Defective blower relay

Front 120

A typical sail switch will close its contacts when the blower wheel reaches what percentage of its rated air flow?

Back 120

75%

Front 121

If so equipped, the heat anticipator can be found

Back 121

in the wall thermostat

Front 122

On a DSI furnace, the circuit board will

Back 122

allow the blower to purge the combustion chamber for a set period of time; open the gas valve; confirm the presence of a burner flame

Front 123

While the furnace is operating, the TDR will draw approximately

Back 123

.2-amp

Front 124

Which component contains a bimetal disk, a coil, and contacts for the thermostat, ground connection and positive 12-volts DC?

Back 124

TDR

Front 125

When troubleshooting the redundant gas valve on the DSI forced air furnace, a good coil will measure

Back 125

30 - 50 Ohms each

Front 126

The voltage range for proper heater operation is

Back 126

10.5 to 13.5 VDC

Front 127

The thermocouple on a gravity heater creates _____ millivolts.

Back 127

20 to 30

Front 128

Forced air gravity heaters should have a voltage of between _____ and _____ at the furnace during operation.

Back 128

10.5 and 13.5 VDC

Front 129

The device that controls the fan causing it to purge the combustion chamber of any residual gases before the furnace attempts to light is called the

Back 129

D.S.I. circuit board

Front 130

The thermostat has an anticipator which will burn out if the TDR and gas value draw more than _____ amps.

Back 130

1.0

Front 131

Some manufacturers recommend replacing the gas solenoid valve on a D.S.I. furnace if the coil is defective. One way to know if a coil is defective is when the resistance is not within a range of _____ ohms.

Back 131

30 to 50

Front 132

The component of a furnace that sends a high voltage spark to the electrode assembly and sends 12 VDC to the gas solenoid valve is the _____.

Back 132

D.S.I. circuit board

Front 133

The central hot water heating system has an electrical heating element which is _____ watts.

Back 133

1650

Front 134

The central hot water heating system has a water and antifreeze ratio of

Back 134

1 to 1

Front 135

To prevent freezing of the water system, adjust the bay thermostat on the central hot water heating system to _____ degrees.

Back 135

40 to 50°F (4 to 10°C)

Front 136

Normal operating temperature for the central hot water heating system is _____ degrees.

Back 136

175 to 200°F (82 to 93°C)

Front 137

Only pure ammonia vapor is present after the contents pass through which component?

Back 137

Rectifier

Front 138

The static pressure of the hydrogen vapor inside the cooling unit

Back 138

is 250 PSI

Front 139

The purpose of sodium chromate inside the cooling unit is to

Back 139

protect the insides of the piping

Front 140

Which component is not associated with the electric operation of the RV refrigerator?

Back 140

Flue

Front 141

In which component does ammonia cool into a liquid?

Back 141

Condenser

Front 142

What removes heat from the ammonia vapor?

Back 142

Air moving through the condenser fins

Front 143

During a refrigerator installation, never allow the side clearances to extend beyond

Back 143

1/2-inch

Front 144

Correct energy source priority for a Norcold automatic refrigerator is

Back 144

120-VAC, LP, 12-VDC

Front 145

Correct energy source priority for a Dometic automatic refrigerator is

Back 145

120-VAC, 12-VDC, LP

Front 146

The absorption refrigerator cooling unit consists of the following components:

Back 146

boiler, condenser, evaporator and absorber

Front 147

Hydrogen Gas has a maximum pressure of _____ PSI when heated.

Back 147

600

Front 148

An excessive amount of heat in the cooling unit will cause

Back 148

both the water and ammonia to vaporize

Front 149

_____ requires the refrigerator to be installed in such a manner as to provide complete separation of the combustion system and the interior atmosphere of the RV.

Back 149

NFPA 1192 /CSA Z240

Front 150

The proper voltage operating range of a 120 VAC, 60 Hz refrigerator is

Back 150

108-132 VAC

Front 151

For the refrigerator to work properly on propane, the propane pressure should be

Back 151

11 " W.C.

Front 152

The proper procedure to clean an orifice assembly is to soak it in

Back 152

an alcohol based solvent

Front 153

If the refrigerator is not running on AC, the first thing to check is the

Back 153

incoming Voltage

Front 154

To bench test an electric thermostat, attach the leads of your VOM to the contacts of the thermostat and test for

Back 154

continuity

Front 155

When a capillary tube has lost its charge, it is necessary to

Back 155

replace the thermostat

Front 156

Where is hydrogen gas combined with liquid ammonia?

Back 156

Evaporator

Front 157

In an absorption refrigerator the _____ vaporizes in the hydrogen gas atmosphere and absorbs heat from inside the refrigerator.

Back 157

ammonia

Front 158

Eye-level ranges are no longer produced because of what inherent factor?

Back 158

They became too costly to the RV manufacturer

Front 159

The pilot flame on an RV range is typically controlled by either a manual on/off valve or by the

Back 159

oven thermostat

Front 160

The oven safety valve

Back 160

contains a thermal bulb which is heated by the standing oven pilot

Front 161

A cooking appliance with top burners only is called a

Back 161

cooktop

Front 162

Care must be taken when replacing burners and orifices to ensure

Back 162

matching of Btu/hr ratings

Front 163

A thermal bulb performs which function?

Back 163

Senses oven temperature

Front 164

Which flame sensing device controls the gas flow to the oven standing pilot?

Back 164

There is no flame sensing device

Front 165

A well adjusted burner flame can be recognized by a

Back 165

crisp blue flame with blue inner crown

Front 166

Burner orifice rating are identified by

Back 166

color

Front 167

When trouble shooting a poorly functioning cooktop burner first check the

Back 167

propane pressure