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Oil Burners Questions and Answers
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According to NFPA31-2001, what is the minimum size of the vent pipe on an oil storage tank ✔✔1 1/4 inch
Nozzles are available with three different spray patterns: ✔✔Solid, semi-hollow, hollow
What type of motor is used on a residential high pressure oil burner ✔✔Split phase
The most common motor speeds used in amerian made burners are ✔✔1725 and 3250 rpm
If an oil has a high viscosity ✔✔It is a thicker oil
A service technician performs a combustion efficiency test. There is too much overfire draft. What can the technician do to decrease the amount of draft in the system ✔✔Open the barometric
A technician arrives on a service call for an oil fired furnace the overfire draft reading is +.02" WC. And the breach is -.04" WC. What could be the cause for this type of problem. ✔✔A plugged heat exchanger
While performing a combustion effiency test on an oil fired furnace. A smoke reading of #5 is obtained. Which of the following could cause this problem. ✔✔Insufficient combustion air
What is a possible problem if an oil fired furnace has a stack temperature reading over 750 degrees F ✔✔Excessive combustion air.
On a stack mount primary control system, the thermostat is set to call for heat. The system sparks but does not fire. A further check shows that the burner motor is not in operation. Which of the following could be the cause of this problem? ✔✔The burner motor could be defective.
On a high pressure gun burner, what two problems can prevent oil from flowing to the nozzle? ✔✔A broken couple in hand a plugged inline filter.
In what position should the cold contacts of a stack relay be at the start up of an oil fired furnace? ✔✔The closed position.
An oil pump has to lift oil from an oil storage tank that is located underground. Each foot of vertical lift will cause a vacuum on the suction line of ✔✔1" hg
If a high pressure gun type oil burner has sufficient spark and adequate oil pump pressure, which of the following could be a cause of system malfunction? ✔✔A plugged nozzle.
In all residential oil heating systems, the high limit control must be ✔✔Line voltage and wire in series with the primary control
When testing a fuel unit cut-off, the pressure at the nozzle port should: ✔✔Drop and hold at about 80% if the pumps pressure setting
Older installations used a remote mounted heat sensing primary control. The type of flame detector is often referred to as the: ✔✔Stack relay
A customer has replaced a mercury bulb thermostat. The furnace heats the house, but tends to cycle on and off several times per hour. The most likely cause would be: ✔✔The anticipator is set too low
The data plate on a residential furnace states that there should be a 70F temp rise. The technician takes a return air temp. Reading of 70F and a supply air temp reading of 180F. Which of the following could be a possible problem. ✔✔The air filter could be dirty.
When a cad cell is sighting flame, it's resistance is: ✔✔Below 1,600 ohms of resistance
When a cad cell is located in the dark, it's resistance is: ✔✔Above 100,000 ohms of resistance
What two flame detection devices are used in oil fired primary controls? ✔✔Bi-metal and cadmium sulfide
Which component is used to control primary air in a high pressure gun burner? ✔✔An adjustable air collar.
Which component is used to increase air velocity in the air tube of a high pressure gun burner. ✔✔The static disk
The flame color characteristics of a high pressure gun burner should be : ✔✔A yellow orange color
Which of the following may prevent ignition of the flame? ✔✔-20F oil
Which of the following statements are true? ✔✔The tips of the electrodes on a high pressure gun burner are positioned just outside the oil stream
Which of the following could cause a stack mount primary control to cycle off on the safety switch? ✔✔Spot build up in the bi metal sensor
The spark gap setting on an electrode assembly should be ✔✔5/16"
The capacity of a high-pressure oil burner nozzle is rated in ✔✔GPH
stack thermometer commonly has a ranger from ✔✔200 to 1000
Atomizing type burners were designed to burn which type of fuel ✔✔No. 2 fuel oil
The use of a _______ will help an oil burner start smoother ✔✔A delayed oil valve
If the F-F terminals on a cad cell primary control are jumped out, what would be the action of the system on start up ✔✔The system would not start.
A service call is received. ✔✔CFM
A technician is servicing an oil fired furnace. ✔✔Terminals 2 and 3
One gallon of No. 2 fuel oil contains approximately ✔✔140,000 BTU's
Pour point problems with above ground fuel tanks containing #1 fuel oil can be partially relieved by ✔✔Relocating the outside fuel filter and strainers to the inside
What does AFUE stand for ✔✔Annual Fuel Utilization Efficiency
insufficient draft due to poor chimney design may be improved by Installing a: ✔✔Draft inducer
The two properties of lightweight combustion chambers are: ✔✔Rapid heat up and rapid cool down
Which of the following is only the efficiency test that can be done in the field ✔✔Combustion efficiency
When installing a vent for outdoor combustion air,NFPA recommends an outdoor air opening of one square inch of free space for every _______ BTU per hour of fuel consumed ✔✔5,
Which of these conditions can cause burner short cycling ✔✔A heat anticipator that is not set properly
When testing an ignition transformer using the arc test method, the arc should be a minimum of: ✔✔1" to 1.25"
Which of the following will affect draft ✔✔Chimney height
If a home has an oil fired system with an inside oil storage tank, what is added as safety feature to protect against liquid fuel fires? ✔✔A fuse type globe valve.
Excess air through the combustion process lowers system efficiency by: ✔✔Increasing flue gas temperature
A burner that has been properly set up and adjusted may still experience an occasional hard start or puff back caused by: ✔✔Low voltage input to the transformer
If a cad cell is "seeing" light when the thermostat calls for heat ✔✔The primary control will not energize
Air is composed of oxygen and nitrogen in what percentages? ✔✔21% oxygen and 78% nitrogen
Pulsating oil pump pressure can be caused by: ✔✔A dogged fuel strainer
Flash point of a fuel is an indication of: ✔✔The lowest temperature that a fuel will flash but not burn continuously
A significant difference between the CO2 reading over the fire and at the flue is an indication of: ✔✔Air leakage in the furnace
When adjusting the electrode assembly of a non-flame retention oil burner, what is the measurement (height) from the center of nozzle to the tip of the electrode ✔✔1/2" to 9/16"
The size of the oil line supplying a burner should be no less than ✔✔3/8" id
If a technician performs a combustion efficiency test on an oil fired furnace and measures too high of a CO reading, which of the following could cause this to happen? ✔✔Not enough air for the fuel air mixture
A technician is servicing an oil fired furnace that uses a cad cell primary control. The control locks out after a brief period of time. Which of the following can cause this to happen? ✔✔The cad cell does not sense light.
When using an intermittent cad cell primary control, which two wires are used to energize the burner motor and ignition transformer with 120V? ✔✔The orange and white wires
Which of the following can cause the oil burner overload protector to trip? ✔✔A seized oil pump
Where is a delayed oil valve installed when used with a high pressure gun burner? ✔✔After the oil pump before the nozzle
What is the purpose of delayed oil valve? ✔✔It delays the oil pressure to the nozzle
Which type of spray pattern is most often used on nozzle rates below 1.0 GPH ✔✔Hollow
What is the purpose of the barometric damper used on an oil fired furnace? ✔✔It controls the draft through the system
What type of lubrication should be used in the burner motor of a high pressure gun burner ✔✔ 20 weight non-detergent type oil
A high CO2 reading in an oil fired furnace could indicate ✔✔A proper and efficient fire
A properly set up and adjusted oil fired furnace should produce a CO2 measurement of ✔✔10% to 12%
