Which Of These Conditions Will Cause The Flame To Lift Off The Burner Surface?

If flue gases are not vented properly,

carbon monoxide poisoning

could result. The gas flame will lift off the burner and be noisy if it receives too much primary air.

What causes flame lift off burner?

Excessive primary air

can cause flames to lift and blow-off the burner ports. … Also, any factor which increases flow velocity from ports contributes to lifting flames. Overrating of burners is also a cause. The normal cure for lifting flames is the reduction of primary air input to the burner.

What causes burner flashback?

Blow-off and flashback are phenomena that limit the operational range of gas turbine engines.

Operating the system with too little fuel or at too high of a velocity

causes the flame to blow away; too much fuel or too low velocity can cause the flame to flashback into the premixing hardware.

What is the possible result if a burner is not supplied with enough gas pressure for proper operation?

Problems with Gas Pressure to Your Furnace

If the gas pressure is too low, your furnace’s efficiency will go down. Not only that, but it will lead to a

greater amount of condensation of burned gases

. That is because the proportion of air in the air-fuel mixture will be too great.

What device is used to automatically stop and start gas flow to the burners?

Definition of

Furnace Gas Valve

A furnace gas valve is a component of your furnace’s fuel system. The furnace gas valve opens and closes, which allows the flow of gas to the pilot light and burner(s). While the component itself if actually rather simple, a furnace gas valve is a crucial part of your HVAC system.

What is flame lift on boiler?

Flame rollout occurs

when burner flames exude from the normal combustion area of

a gas boiler or furnace. Like furnaces, gas boilers incorporate a heat exchanger that accepts hot combustion gases produced by the burner, then transfers heat to the water.

What is flame lift-off length?

Low-Temperature Combustion (LTC) is becoming a promising technology for simultaneously reducing soot and NOx emissions from diesel engines. LTC regimes are evaluated by the flame lift-off length –

the distance from the injector orifice to the location of hydroxyl luminescence closest to the injector in the flame jet

.

What is flashback in boiler?

Flashback – A

phenomenon occurring only in pre-mix gas burners when the flame speed overcomes the gas-air mixture flow velocity exiting the gas tip

. The flame rushes back to the gas orifice and can make an explosive sound when flashback occurs. Flashback is most common when hydrogen is present in fuel gas.

What does a flash arrestor do?

A flame or flashback arrestor is a

safety device designed to stop a flame in its tracks

. It is therefore used to prevent flashback into cylinders or pipework.

What helps to keep the flame retained at the burner port of a mono port burner?

What could result if a flame is adjusted with too much primary air?

The

gas flame will lift off the burner and be noisy

if it receives too much primary air. … Flame is air starved. The flame in a gas fired furnace is burning with heavy yellow tips.

What will happen when the boiler has low combustion air pressure?

Too little

air and combustion will be incomplete

, unburned fuel will be carried over and smoke may be produced.

What causes flue gas condensation quizlet?

What causes flue gas condensation?

The flue gas is cooled below the dewpoint of the combustion gas

.

What causes soot buildup in the heat exchanger and vent?

Soot Build-Up

Soot develops due to

accumulations of carbon within the furnace

. This is usually the case when the furnace is not clean and completely burning fuel, as the result of a poorly adjusted burner or a cracked heat exchanger.

What are four factors that determine the efficiency of a furnace?

What are four factors that determine the efficiency of a furnace? Factors that determine the efficiency of a furnace are

the type pf draft, the amount of excess air, the temperature difference of the air or water entering versus leaving the heating medium side of the heat exchanger, and the flue stack temperature.

What is pulled into the burner prior to ignition and mixes with the gas for combustion?

Introduction. Air for combustion can be supplied to the burner in several ways.

Primary air

is a term used to describe air supplied and mixed with fuel prior to ignition.

What is lift-off length?

The lift-off length in the simulation is defined as

the axial distance from nozzle exit to 14% of maximum OH in the quasi-steady state

.

What is the other term for flame arrestor?

A flame arrester (also spelled arrestor),

deflagration arrester

, or flame trap is a device that stops fuel combustion by extinguishing the flame.

What causes furnace rollout?

Rollout is caused by the combination of gases and flames present when the furnace is in operation. When the furnace is on, flames ignite and are meant to remain inside the combustion chamber. In some cases, gases which are not flammable will build inside

the

chamber, which prevents oxygen from getting to the flames.

What is flame stability?

In house and industrial applications flame stability is achieved by

attaching the flame to

a simple device known as a burner. Flame stabilization is usually accomplished by causing some of the combustion products to recirculate and hence to continually ignite the fuel mixture.

What is backfire in gas welding?

Backfire is

the momentary retrogression or burning back of the torch flame

, into the welding or cutting torch tip accompanied by a loud popping sound and also accompanied by the immediate reappearance or the complete extinguishments of the flame.

What are the four components of a flashback arrestor?

• Non-Return Valve: this stops the reverse flow (back surge) of gas.
• Sintered Flame Filter: this blocks the flame.
• Thermal Activated Cut-Off Valve: (fitted to regulator mounted models only).

What is a multi port burner susceptible to?

Crimped ring. What is multi port burner susceptible to.

Clogging with lint from the inside

.

What does a barometric damper control quizlet?

Single-acting barometric damper: Is

a draft control device intended to stabilize the natural draft in an appliance by admitting room air to the venting system

.

Where is secondary air induced into the furnace?

Secondary air – Air which is introduced into a furnace (in addition to the primary air which enters either as a mixture with fuel or as blast underneath a stoker)

above or around the flames

to promote combustion.

What causes flue gas condensation?

What causes the condensation in a boiler flue? …

With more heat entering the process there is less heat exiting out the

boiler flue. The water vapor formed during the combustion is less likely to remain a vapor. As the temperature of the flue gas cools below “Dew Point”, the water changes state to a liquid.

What would flue gas symptoms be if there were too much airflow?

Too much excess air

leads to lower flame temperature

. That means less heat gets into the system. Also, excess air must heat up to flue gas temperature, which consumes extra energy.

What happens when there is too much primary air?

Too much primary air— Primary air is

the air mixed with the gas before it’s ignited

. Too much primary air makes the gas-air mixture hard to light, causing gas to build up. … Too little gas at the burners—Like too much air, not enough gas makes it hard for the gas-air mixture to ignite.

What would cause a fan switch to close?

The switch’s sensor becomes dirty and stops working correctly. The

furnace filter is clogged

and raises the temperature within the plenum prematurely, tripping the sensor. The blower motor stops working and overheats. … These may cause the fan limit switch to stop working properly.

How does the flame rod sense the flames in a flame rectification circuit?

How does the flame rod sense the flames in a flame rectification circuit?

The flame changes the AC voltage to pulsed DC current

. … A small flame that is used to light the main burners.

How is soot formed quizlet?

Hydrocarbon + O2 = CO2 + H2O + energy

Fuel reacts with a limited supply of oxygen to produce carbon (soot), carbon monoxide, carbon dioxide and water vapour, depending on the amount of oxygen available.

What factors affect boiler efficiency?

Some of the factors that affect the efficiency of the boiler is a

superheater pressure, water feed temperature, steam temperature, the amount of steam produced, the amount of fuel consumption and calorific value fuel combustion

.

How does air react with combustion?

When a hydrocarbon fuel is burned in air, combustion products change the composition significantly. Atmospheric

oxygen is consumed to oxidize the hydrogen and carbon

, creating water and carbon dioxide respectively.

What is combustion air?

Air for Combustion

Combustion is a chemical process in which, the fuel combines with

oxygen gas

to release energy in the form of heat and light. This heat can be used to produce electricity, run our cars and also for cooking.

What causes soot in gas furnace?

Incomplete Combustion

As the furnace in your house burns fuel to create heat, especially natural gas, there are remnants left over after the process is completed. … One of the combustion byproducts is

carbon

, the primary ingredient in black soot, which is sent up the heat exchanger and out of the house.

What causes soot build up?

Soot buildup is commonly caused by

clogged burner ports and improperly positioned fire-logs

. A fire-log that’s out of position can obstruct the flame path that ensures the clean-burning of gas. This contributes to soot formation on the fireplace. Another primary cause of soot is clogged gas burner ports.

What causes soot in propane furnace?

Clogged oil nozzles or gas orifices

can lead to improper combustion, causing the formation of soot. Household dirt or contaminated fuel is usually the cause, so you should have your HVAC contractor inspect the nozzles and clean or replace them if necessary.