Combustion Analysis And Heat Exchanger Testing Nait Plumbing Fourth-Year Theater

Front 1

What is the ultimate CO2 in a flue gas sample?

Back 1

12% by volume

Front 2

When the production of CO2 diminishes, what happens to the co production

Back 2

Increases

Front 3

What will happen to the flue gas temperature if the appliance afue efficiency increases?

Back 3

Decreases

Front 4

What will happen to combustion efficiency if too much air is added to the combustion Zone?

Back 4

Decreases

Front 5

When testing for CO2 in a flue gas sample, what kind of results do we want?

Back 5

The percentage of CO2 in the sample should be as high as possible

Front 6

Why is it important to determine the amount of unburned oxygen in a flue gas sample?

Back 6

To determine which side of the ultimate CO2 scale we are on

Front 7

What result would be best when determining the O2 percentage in the flue gas?

Back 7

The percentage of o2 in the sample should be low. Less than eight percent

Front 8

How is net flue gas temperature determined

Back 8

Subtract ambient temperature from the flue gas temperature

Front 9

What would be the normal draft in the vent for a category 1 draft Hood Appliance?

Back 9

About 0.03 in water column negative pressure

Front 10

What results are required to determine the combustion efficiency of a gas-fired Appliance?

Back 10

The CO2 and the net flue-gas temperature

Front 11

If oxygen from the air burns in the combustion process, why would oxygen be present in the flue gas?

Back 11

This is from the unused excess air

Front 12

Common scent based test used to find a crack in a heat exchanger

Back 12

Sulfur test or Wintergreen test

Front 13

When the blower motor comes on normally stable Flames now become unstable and blow all over the place what is the most likely cause?

Back 13

Cracked heat exchanger

Front 14

What must be done with the furnace in the house that is found to have a cracked heat exchanger?

Back 14

The heat exchanger must be replaced

Front 15

What is the biggest concern if a furnace and a house has a cracked heat exchanger?

Back 15

Possibility of flame rollout and eventual carbon monoxide production

Front 16

Primary air

Back 16

Provides percentage of the combustion air but more importantly, it controls the amount of fuel that can be burned efficiently

Front 17

Secondary air

Back 17

Increases combustion efficiency by causing the fuel to completely burn

Front 18

Do power burners require secondary air

Back 18

No

Front 19

Excess air

Back 19

Is supplied to the combustion Zone is air an excess of the air which is theoretically required for combustion

Front 20

Dilution air

Back 20

Does not directly promote the combustion process but is used to control the stack effect and reduce the probability that moisture formed by the combustion of fuel will condense in the venting system

Front 21

What flame characteristics should a category 1 Appliance have

Back 21

Slightly carbonizing

Front 22

Water heater burner flame should have what characteristics

Back 22

Neutral

Front 23

Range top burner flame characteristics

Back 23

Slightly oxidizing

Front 24

What type of combustion is achieved in a gas burning Appliance

Back 24

Complete combustion

Front 25

What are the first products produced by incomplete combustion

Back 25

Aldehydes

Front 26

Which portion of the air supplies theoretically not required for combustion

Back 26

Excess air

Front 27

Which portion of the Air Supply is used to tune the burner

Back 27

Excess air

Front 28

Which efficiency rating accounts for standby losses

Back 28

Annual fuel utilization efficiency or afue

Front 29

Which of the following fuels has the highest hydrogen to carbon ratio, coal, wood, heating oil, propane gas?

Back 29

Propane gas

Front 30

What happens to the efficiency of an appliance if the temperature of the combustion air is drastically lowered?

Back 30

Decreased

Front 31

What happens to the efficiency of the appliance if the primary air shutter is adjusted?

Back 31

Little to no difference

Front 32

What is the importance of determining the temperature rise of a forced air furnace?

Back 32

Ensures that the flue gases are transferring the correct amount of heat

Front 33

How is the temperature rise on a forced air furnace changed?

Back 33

Circulating air blower speed is changed

Front 34

What is the importance of determining the oxygen content of the flue gas

Back 34

Allows the amount of excess air entering the appliance to be determined

Front 35

What number do you multiply an oxygen reading by to get the percentage of excess air

Back 35

5

Front 36

Maximum carbon monoxide exposure level for an 8 hour time frame

Back 36

25 PPM

Front 37

When testing the pressure in the vent, one opening of the draft gauge connects to the vet. Where does the other opening connect?

Back 37

Atmosphere

Front 38

Where should the flue gas sample be taken from

Back 38

In the combustion chamber Upstream of the draft control device

Front 39

What does a very low vent draft indicate

Back 39

The appliance is grossly under fired

Front 40

What adjustment is required for an appliance with a CO2 reading of 7% and an O2 reading of 12%?

Back 40

Excess air should be reduced

Front 41

What is a common cause for cracks in heat exchangers

Back 41

Metal fatigue due to heat / cool Cycles

Front 42

What heat exchanger test requires the use of a butane torch

Back 42

The sodium ion test