NORA BRONZE STUDY GUIDE QUESTIONS WITH COMPLETE SOLUTIONS

NORA BRONZE STUDY GUIDE QUESTIONS WITH COMPLETE SOLUTIONS “How many BTU's does one gallon of #2 fuel contain? - CORRECT ANSWER 139,000" "When the viscosity of fuel entering the nozzle increases the_____________ increases: - CORRECT ANSWER The flow rate also increases" "Dirt or lint build up on fan blades or air inlet will: - CORRECT ANSWER Reduce the amount of combustion air" "High static pressure produced by oil burners: - CORRECT ANSWER Allow manufacturers to create tighter heat exchangers for increasedefficiency" "High static pressure burners have been developed to: - CORRECT ANSWER to push the products of combustion through the heat exchanger of high efficiency appliances" "How far from any open flame or fuel burning appliance must an oil tank be installed? - CORRECT ANSWER 5'" "Can cast iron fittings be used on oil tank piping? - CORRECT ANSWER No" "When nozzles are dirty or plugged, they should be: - CORRECT ANSWER Replaced" "Nozzles are normally cooled by: - CORRECT ANSWER The air & fuel travelling past or through them" "The burner air tube should be installed ________________ back fromthe inside wall of the combustion chamber. - CORRECT ANSWER ¼"" "Nozzle after drip can be caused by: - CORRECT ANSWER Bad pump shutoff (PRV), air in nozzle line" "Fuel must burn completely in suspension without touching what? - CORRECT ANSWER The crown sheet, chamber floor or walls" "True or false, ideally combustion chambers should be designed to both heat up and cool off quickly: - CORRECT ANSWER True" "If a chamber is too small, or the nozzle is too close to the chamber floor there will be: - CORRECT ANSWER Impingement" "With no insulating material between the heat exchanger and the hot flue gasses, heat transfer to the water is - CORRECT ANSWER Better" "Combustion tests give us the "steady state" efficiency of the unit. We test: - CORRECT ANSWER The composition of the gasses (excess air), smoke concentration,temperature of the gasses, draft through the unit" "True or False, the more efficient the appliance the higher the stacktemperature will be: - CORRECT ANSWER False" "What is "steady state"? - CORRECT ANSWER At steady state there are no changes in the combustion gases. The unit has thoroughly warmed-up and will maintain constant conditions as long as the burner runs." "Proper location of the hole in the flue pipe for combustion testing is: - CORRECT ANSWER In the flue pipe near the appliance outlet (the breech)." "How many strokes are necessary when performing a smoke test? - CORRECT ANSWER 10 full strokes" "An electrical load is a device which converts electrical energy into: - CORRECT ANSWER Another form of energy to perform "work"" "Step-down transformers have more: - CORRECT ANSWER Primary coils than secondary coils and reduce voltage" "Step up transformers have more: - CORRECT ANSWER Secondary coils than primary coils and increase voltage" "In residential systems, high limit controls are: - CORRECT ANSWER Automatic, line voltage, temperature or pressure activated switches, wired in series with the primary control." "The fan & limit control on a warm air system is used: - CORRECT ANSWER To turn the burner off at a set temperature, and turn the blower on and off at set temperatures" "Average warm air limit settings: - CORRECT ANSWER 200°F Limit, 140°F Fan = On, 110°F Fan = Off" "What commonly causes a burner on a warm air system to go off on high limit: - CORRECT ANSWER Fan failure, clogged air filters, or broken blower belt" "High limit aqua stats prevent: - CORRECT ANSWER Boiler water temperature rising to unsafe levels" "Low limit (operating) aqua stats prevent: - CORRECT ANSWER Boiler water temperature dropping below a set point" "Switching relays allow control of: - CORRECT ANSWER A line voltage load with a low voltage control (like a thermostat)" "When mounting a thermostat, it should be: - CORRECT ANSWER About 5' from the floor, on an inside wall, away from heat emitters, and away from windows & outside doors" "The end switch on a zone valve is commonly wired to: - CORRECT ANSWER T-T on the boiler temperature control" "Primary controls have three basic functions: - CORRECT ANSWER Respond to the thermostat, respond to the limit control, and supervise the starting, running & stopping of the burner" "Intermittent Ignition is: - CORRECT ANSWER Spark on whenever burner runs" "Interrupted Ignition is: - CORRECT ANSWER Spark remains on for a short time at the beginning of each cycle, then isturned off once flame is established" "When the light intensity on the cad cell increases (gets brighter) the resistance (OHMS): - CORRECT ANSWER decreases" "Before pressing the reset on a primary control: - CORRECT ANSWER Check for oil in the chamber" "What is Pre purge (Valve delay on) on a primary control: - CORRECT ANSWER It lets the burner get up to speed and deliver full combustion air before introducing oil, cleaner starts" "What is Post purge (Valve delay off) on a primary control: - CORRECT ANSWER It allows all combustion gasses and excess heat to dissipate, cleaner shutdowns" "Odor, soot, smoke, puff-back. What could cause it? - CORRECT ANSWER Ignition issue, plugged chimney base, whole house fan." "The best burner adjustment is one that allows for a smokeless operation with a minimum of excess air, typically: - CORRECT ANSWER 25% - 35%" how many btus does one gallon of #2 fuel contain? - CORRECT ANSWER 139,000 BTU's" "pour point - CORRECT ANSWER lowest temp fuel will flow" "cloud point - CORRECT ANSWER The temperature at which wax crystals first start to form" "fire point - CORRECT ANSWER The lowest temperature fuel will ignite at" "using additives can? - CORRECT ANSWER lower pour point and cloud point" "flash point - CORRECT ANSWER lowest temp a fuel can be safely stored/handled" "sulfur exists in? - CORRECT ANSWER varying degrees in all fossil fuels" "why is heating oil red? - CORRECT ANSWER to differentiate fuels (tax reasons)" "what is bioheat a blend of? - CORRECT ANSWER #2 fuel and B100 biodiesel" "pulsating fuel pressure can be caused by? - CORRECT ANSWER partial clog, air, slipping coupling, or high vacuum" "(for vacuum) if the gauge reading is significantly above the calculated reading it could be? - CORRECT ANSWER plugged filter/line, kink in line." "NORA recommends that fuel lines that have blockages be cleared with what? - CORRECT ANSWER hand pump to pull it out" "If the gauge reading is significantly below the calculated reading it could be? - CORRECT ANSWER Air leak in suction line, air leak on strainer gasket." "How do you calculate the approximate operating vacuum of a fuel unit? - CORRECT ANSWER 1" Hg filter, 1" Hg 10' of horizontal and 1" Hg 1' vertical" "why is 1 pipe preferred over 2 pipe systems? - CORRECT ANSWER extended filter life, return line leak" "what is recommended by NORA whenever fuel tank is higher than the fuel unit? - CORRECT ANSWER oil safety valve" "T or F, fuel unit rotation is opposite of burner motor rotation - CORRECT ANSWER True" "What are the nozzle functions? - CORRECT ANSWER Spray pattern, meter, atomization" "The best burner adjustment is one that allows for a smokeless operation with a minimum of excess air, typically? - CORRECT ANSWER 25%-35%" "For proper installation of a nozzle heater, it must be wired in? - CORRECT ANSWER Parallel of limit control" "GPH is clearly stamped on each nozzle and box and is based on? - CORRECT ANSWER 100 PSI" "To combat cold oil problems, you can? - CORRECT ANSWER treat oil with additives, nozzle heater, (increase pressure and decrease nozzle size)" "increasing the fuel pump operating pressure to 140 PSI will? - CORRECT ANSWER result in better atomization" "in increase in viscosity results in? - CORRECT ANSWER bigger droplets, increase firing rate" "When tightening a nozzle in the drawer assembly be sure to tighten to - CORRECT ANSWER approx 1/8 to 1/4 past hand tight" "When nozzles are dirty or plugged, they should be? - CORRECT ANSWER replaced" "Nozzles are normally cooled by? - CORRECT ANSWER Air, oil, fuel" "combustion tests give us the "steady state" efficiency of the unit. we test: - CORRECT ANSWER composition of gases, smoke concentration, temp of gases, and draft to appliance" "Carbon monoxide is produced by incomplete combustion which can be caused by? - CORRECT ANSWER Too little or too much combustion air" "an 1/8" of spot on the heat exchanger can increase fuel consumption by? - CORRECT ANSWER 8%" "T or F, the more efficient the appliance the higher the stack temp will be. - CORRECT ANSWER false" "what is "steady state"? - CORRECT ANSWER no changes in combustion gases, unit warmed, maintain constant conditions while burner is on" "proper location of the hole in the flue pip for combustion testing is? - CORRECT ANSWER 1 flue pipe diameter away from damper, 2 diameters from breach or elbow" "how many strokes are necessary when preforming a smoke test? - CORRECT ANSWER 10" "before using electronic analyzer, you must? - CORRECT ANSWER Perform a smoke test." "it's important to set smoke to trace or zero because? - CORRECT ANSWER over air or to much smoke leads to soot" "when a new appliance is installed, manufacturing residue often causes temporarily elevated ___ levels. - CORRECT ANSWER CO/ Carbon monoxide" "electrical force or potential is measured in? - CORRECT ANSWER Volts" "a voltmeter measures? - CORRECT ANSWER potential difference" "a series circuit has how many paths? - CORRECT ANSWER 1" "a parallel circuit has how many paths? - CORRECT ANSWER multiple" "step down transformers have more ___ - CORRECT ANSWER primary coils" "step up transformers have more - CORRECT ANSWER secondary coils" "In residential systems, high limit controls are? - CORRECT ANSWER line voltage - are activated by temp or pressure, wired in series with primary control" "the fan and limit control on a warm air system is used - CORRECT ANSWER To turn the burner and the blower on/off at set temperatures." "Average warm air limit settings? - CORRECT ANSWER 200°F high Limit, 140°F Fan = On, 110°F Fan = Off" "What commonly causes a burner on a warm air system to go off on high limit? - CORRECT ANSWER clogged filter, broken blower belt, fan motor" "High limit aquastats prevent? - CORRECT ANSWER Boiler water temperature rising to unsafe levels." "Low limit (operating) aquastats prevent? - CORRECT ANSWER boiler water dropping below set point" "switching relays allow control of? - CORRECT ANSWER line voltage with a low voltage control (like a thermostat)." "when mounting a tstat it should be? - CORRECT ANSWER on a inside wall, 5ft up, away from heat emitters, no windows or outside doors" "the end switch on a zone valve is commonly wired to? - CORRECT ANSWER T-T on the boiler controls" "primary controls have three basic functions: - CORRECT ANSWER responds to tstat, limits, controls running and stopping the burner" "primary control accomplishes its functions by - CORRECT ANSWER reacting to flame, managing start up and shutdown" "Intermittent ignition is - CORRECT ANSWER igniter on entire run cycle" "Interrupted Ignition is? - CORRECT ANSWER igniter on set time" "when the light intensity on the cad cell increases (gets brighter) the resistance (ohms) - CORRECT ANSWER decrease" "Before pressing the reset on a primary control? - CORRECT ANSWER Check for oil in the chamber." "what is pre purge (valve delay on) on a primary control - CORRECT ANSWER optimized air/fuel mixing during start up, reduces soot and increases efficiency" "what is the post purge (valve delay off) on a primary control? - CORRECT ANSWER motor and fan deliver full air flow for set time after oil stops" "electric motors serve many purposes in the oil heat industry, but most commonly: - CORRECT ANSWER deliver air and fuel for combustion, circulators, blower motors" "ECM, "electronically commutated" motors feature: - CORRECT ANSWER variable speed cap and efficiency" "Burner motors with fewer air holes in the shaft bell generally provide? - CORRECT ANSWER Higher static pressure" "Most burner motors produced today do NOT need? - CORRECT ANSWER oil" "what are the two major components of a psc motor to troubleshoot - CORRECT ANSWER capacitor and windings" "Three-piece circulators feature a bearing assembly that connects the motor to the pump body. The bearing assembly shaft is connected to the motor shaft by a pump coupling. When a coupling breaks check: - CORRECT ANSWER motor mounts" "a solid state igniter utilizes electronics to produce an output voltage between: - CORRECT ANSWER 14,000 to 20,000 volts" "why is intermittent ignition considered to be worse? - CORRECT ANSWER reduces life of electrodes and transformer, nox higher, combustion problems maybe hidden" "can you repair cracked ceramic insulators on electrodes? - CORRECT ANSWER No" "what is the purpose of a circulator? - CORRECT ANSWER creates pressure difference to move more water" "12 PSI "pushes" water how high? - CORRECT ANSWER 28ft approx, 1 PSI = 2.31 ft of water" "a single pipe that goes from the boiler outlet through each piece of ___ - CORRECT ANSWER Heat distribution unit (base boards, etc)" "what makes a one pipe system different from a series loop system? - CORRECT ANSWER series loop: less heat at end of HDU one pipe: special tee configuration each Heat distribution unit sees approximately same temperature" "residential hot water boiler relief valves are set to open at? - CORRECT ANSWER 30 psi" "No residential steam heating system should operate at more than? - CORRECT ANSWER 2 psi" "the LWCO on a steam system shuts down the burner when? - CORRECT ANSWER water drops to unsafe level" "On steam boilers the relief valve is set to open at? - CORRECT ANSWER 15 psi" "all water heaters with storage capacity must have a? - CORRECT ANSWER Temperature and pressure relief valve" "how do you ensure the system is operating efficiently and reliably during a preventative maintenance call? - CORRECT ANSWER Combustion test" "what controls should be tested during a preventative maintenance call? - CORRECT ANSWER all limit controls, primary control" "NORA recommends that during a preventative maintenance call the oil tank be checked for? - CORRECT ANSWER water and leaks" "how should you approach a service call? - CORRECT ANSWER systematically" "Reset Pressed -Nothing Happens. What should be checked? - CORRECT ANSWER Voltage, Cadcell (flame light) (dark: over 20,000 ohms) (light: 1,600 ohms)" "on a no heat call: you press the reset and the burner runs. what do you do? - CORRECT ANSWER Begin your testing routine, determine why it went off, make all necessary repairs to correct the problem and to keep it from re-occurring." "Odor, soot, smoke, puff-back. What could cause it? - CORRECT ANSWER Ignition issues, chimney issues" "temperature rise in a furnace is: - CORRECT ANSWER difference in temp between the supply air and the return air" "Using ultra low sulfur diesel (ULSD) all but eliminates: - CORRECT ANSWER soot and scale formation" "Codes require that oil-heat systems shall be wired: - CORRECT ANSWER in dedicated circuits" "Flash point is: - CORRECT ANSWER The maximum temp a fuel can be safely stored & handled without serious fire hazard" "Fire point is: - CORRECT ANSWER Ignition point is the lowest temperature at which fuel vapor will initiate andsustain combustion" "Pour point is: - CORRECT ANSWER The lowest temperature at which fuel will flow" "Cloud point is: - CORRECT ANSWER The temperature at which wax crystals begin to form." "Using an additive can: - CORRECT ANSWER Lower pour and cloud points" "Sulfur exists in: - CORRECT ANSWER Varying degrees in all fossil fuels" "Using ULSD all but eliminates: - CORRECT ANSWER Scale and soot formation" "Why is heating oil dyed red? - CORRECT ANSWER To differentiate it from on-road diesel fuel" "What is Bioheat a blend of? - CORRECT ANSWER A blend of #2 fuel and B100 Biodiesel" "What is combustion? - CORRECT ANSWER The rapid reaction of a combustible material with oxygen, involvingthe production of heat and light" "What three things are required for combustion to take place: - CORRECT ANSWER Oxygen, fuel, heat" "What three electrical components does the primary control operate? - CORRECT ANSWER The burner motor, igniter, and oil valve" "An oil burner motor is responsible to create the force needed to turn: - CORRECT ANSWER The burner fan and fuel unit" "The burner motor drives: - CORRECT ANSWER The fan and a fuel unit" "The fuel units' function is - CORRECT ANSWER Moves fuel from the tank, pressurizes it and delivers it to the nozzle provide fast and complete cutoff of fuel on burner shutdown" "What is primary air? - CORRECT ANSWER Air that exists through the center opening." "What is secondary air? - CORRECT ANSWER Air that exits through the slots cause the air to spin enabling the best mix offuel and air" "What is tertiary air? - CORRECT ANSWER Air that exits around the outside of the flame retention ring and blankets the fuel with air to ensure clean combustion" "The difference between fixed and adjustable heads: - CORRECT ANSWER Fixed heads are attached and have a pre-set tertiary air opening, an adjustable head is attached to the nozzle assembly and is moved to change the tertiary air opening" "The key final adjustment for most burners is: - CORRECT ANSWER Combustion air" "Burner fan blades need to be clean of debris to ensure: - CORRECT ANSWER Proper amount of combustion air is delivered" "A tank without a functioning vent alarm should: - CORRECT ANSWER Not be filled until the vent alarm is repaired or replaced" "Tanks should be kept free of water because: - CORRECT ANSWER It leads to corrosion and provides a home for harmful bacteria" "Condensation in outdoor tanks can be reduced by: - CORRECT ANSWER Setting it in an enclosure, painting it a light color" "For normal residential use, what size oil line is recommended? - CORRECT ANSWER 1/2" O.D. fuel lines (3/8" I.D.)" "Fuel lines that contact concrete or dirt must be: - CORRECT ANSWER coated or sleeved in plastic" "In general, the right size tank is one that holds: - CORRECT ANSWER About one-third (1/3) of the customer's annual fuel consumption" "Pulsating fuel unit pressure can be caused by: - CORRECT ANSWER Slipping coupling, excessive vacuum, partially clogged strainer, air leak" "If the gauge reading is significantly above the calculated reading it could be: - CORRECT ANSWER Plugged filter, plugged/kinked line, stuck check valve" "True or false, NORA recommends that pumping "clean" oil from an oldtank into a new tank is ok: - CORRECT ANSWER False" "NORA recommends that fuel lines that have blockages be cleared with: - CORRECT ANSWER Hand pumps to pull blockages out" "If the gauge reading is significantly below the calculated reading it could be: - CORRECT ANSWER Clogged strainer, air leak in suction line, air leak around gasket" "How do you calculate the approximate operating vacuum of a fuel unit? - CORRECT ANSWER 1" Hg for every foot of vertical lift, 1" Hg for every 10' of horizontal run, ½"to 1" Hg for clean filter." "Why is 1 pipe preferred over 2 pipe systems? - CORRECT ANSWER 1 pipe systems reduce the possibility of return line leaks and extend filter life" "What is recommended by NORA whenever fuel tank is higher than the fuel unit? - CORRECT ANSWER Oil Safety Valves" "True or False, Fuel unit rotation is opposite of burner motor rotation: - CORRECT ANSWER True" "What are the nozzle functions: - CORRECT ANSWER Atomize the oil, provide a spray pattern, and deliver a fixed quantity ("meter the oil")" "The best burner adjustment is one that allows for a smokeless operationwith a minimum of excess air, typically: - CORRECT ANSWER 25% - 35%" "For proper installation of a nozzle heater, it must be wired in: - CORRECT ANSWER Parallel with the limit control, not in series" "Gallons per hour is clearly stamped on each nozzle and box and is based on: - CORRECT ANSWER A flow of 100 PSI." "To combat cold oil problems, you can: - CORRECT ANSWER Install a fuel de-aerator, install a nozzle line heater, add additives or use #1fuel, increase pump pressure and drop nozzle size" "Increasing the fuel pump operating pressure to 140 psi will: - CORRECT ANSWER Increase flow rate, reduce droplet size, reduce angle, make pattern more solid" "An increase in viscosity results in: - CORRECT ANSWER Increase flow rate, increase droplet size, increase angle, make pattern more hollow" "When tightening a nozzle in the drawer assembly be sure to tighten to: - CORRECT ANSWER Tighten no more than ¼ turn with wrench beyond hand tight" "What is the purpose of the venting system? - CORRECT ANSWER Safely Removes products of combustion to the outdoors" "Thermal draft is created when? - CORRECT ANSWER The air in the chimney is hotter and therefore lighter (less dense) than the air outside" "What types of draft and venting can be found on appliances? - CORRECT ANSWER Natural draft, induced draft, power venting, and direct venting" "What is meant by draft "drop"? - CORRECT ANSWER It is when draft measured over the fire is lower than the draft measured at the breech" "If draft over the fire (norm = -.01 to -.02"W.C.) is significantly lower than at the breech the unit may be: - CORRECT ANSWER Over-fired, be overly restricted (plugged heat exchanger), or have air leaks" "The most important measurement of draft is? - CORRECT ANSWER Draft over the fire" "Why is a draft regulator required with chimney vented appliances? - CORRECT ANSWER Draft produced by a chimney is variable and needs to be maintained" "What are the 4 most common requirements when installing new flue pipe? - CORRECT ANSWER 18 inches from combustibles, ¼" per foot pitch, should be firmly joined with sheet metal screws and properly supported" "If 2 openings are provided into 1 chimney flue, they shall be at different levels, what appliance would be at the higher level? - CORRECT ANSWER The appliance with the lower firing rate shall enter at the higher level" "What is 1 cause of insufficient air for combustion? - CORRECT ANSWER Less air leaks into modern buildings because of new construction practices" "What is the best solution for insufficient combustion air? - CORRECT ANSWER Install isolated combustion a.k.a an outside air connection to the burner" "True or False, a draft regulator can increase the draft from the chimney or power venter. - CORRECT ANSWER False" "Which factors cause variable draft and require draft regulators to maintain steady draft? - CORRECT ANSWER Humidity, Barometric Pressure, Air Temperatures" "Natural draft is divided into two categories. What are they? - CORRECT ANSWER Thermal and Currential" "Draft for a direct vented appliance is produced by: - CORRECT ANSWER The static pressure created by the burner fan" "Air contains how much oxygen and nitrogen? - CORRECT ANSWER 21% oxygen and 78% nitrogen" "# 2 Fuel is Approximately ______ % Carbon. - CORRECT ANSWER 85" "To prevent CO from entering the home we will need to: - CORRECT ANSWER Properly adjust the oil burner, ensure the venting system is installed correctly" "An 1/8" of soot on the heat exchanger can increase fuel consumption by: - CORRECT ANSWER 8%" "Carbon Monoxide is produced by incomplete combustion which can because by? - CORRECT ANSWER Too little or too much combustion air" "Before using electronic analyzer you must: - CORRECT ANSWER Perform a smoke test" "It's important to set smoke to a trace or zero because: - CORRECT ANSWER Higher smoke settings lead to soot creation which insulates the heatexchanger surfaces and lowers efficiency" "As excess air is added: - CORRECT ANSWER CO2% goes down and the 02 goes up." "Too much draft over the fire causes combustion gases to travel: - CORRECT ANSWER Too rapidly through the heat exchanger" "When a new appliance is installed, manufacturing residue often causestemporarily elevated _____________________levels. - CORRECT ANSWER carbon monoxide" "Codes require that Oil-heat systems shall be wired: - CORRECT ANSWER In dedicated circuits." "Electrical force or potential is measured in: - CORRECT ANSWER Volts" "A voltmeter allows: - CORRECT ANSWER Very little current flow and are used on "live" circuits to measure the difference in potential." "A series circuit has __________ path. - CORRECT ANSWER 1" "A parallel circuit has ___________ paths. - CORRECT ANSWER multiple" "In an energized 120 VAC circuit, when a voltmeters leads are placed on both sides of a toggle switch in the closed position, the reading will be: - CORRECT ANSWER 0 VAC" "Electrical "current" describes the amount or rate of electricity flowing through a circuit, and it is measured: - CORRECT ANSWER Amperes (amps)" "A clamp on ammeter converts: - CORRECT ANSWER The strength of the magnetic field surrounding the wire into an amperage reading" "Materials that offer very little resistance to the flow of current are called: - CORRECT ANSWER Conductors" "What is a good insulator at 120 V but is a good conductor at 10,000 V? - CORRECT ANSWER Air" "When measuring resistance to flow in an electrical circuit, set the meter to the ________ scale. - CORRECT ANSWER Ohms" "Most burner motors produced today do NOT need: - CORRECT ANSWER To be lubricated" "There are two major components of a PSC motor to troubleshoot: - CORRECT ANSWER The capacitor and the windings" "Three-piece circulators feature a bearing assembly that connects the motor to the pump body. The bearing assembly shaft is connected to the motor shaft by a pump coupling. When a coupling breaks check: - CORRECT ANSWER The motor mounts & replace as needed" "A solid state igniter utilizes electronics to produce an output voltage between: - CORRECT ANSWER 14,000 to 20,000 volts peak" "Why is intermittent ignition considered to be worse? - CORRECT ANSWER Transformer life is reduced, noise is increased, combustion problems maybe hidden electrode life is reduced and NOx emissions are higher" "Can you repair cracked ceramic insulators on electrodes? - CORRECT ANSWER No" "What is the purpose of a circulator? - CORRECT ANSWER Create a pressure difference that produces flow in the system" "12 PSI "pushes" water how high in a pipe? - CORRECT ANSWER 28 feet" "A single pipe that goes from the boiler outlet through each piece of radiation and back to the boiler inlet is what type of piping system? - CORRECT ANSWER Series loop" "What makes a one pipe system different from a series loop system? - CORRECT ANSWER All of the sections of radiation are connected to the single pipe main by these of a standard tee and a special tee that form a "branch" of the main circuit." "Residential hot water boiler relief valves are set to open at: - CORRECT ANSWER 30 PSI" "No residential steam heating system should operate at more than: - CORRECT ANSWER 2 PSI" "The low water cut off on a steam system shuts down the burner when? - CORRECT ANSWER The water drops to an unsafe level" "On steam boilers the relief valve is set to open at: - CORRECT ANSWER 15 PSI" "All water heaters with storage capacity must have a: - CORRECT ANSWER Temperature and pressure relief valve" "Temperature rise in a furnace is: - CORRECT ANSWER The difference in temperature between the supply air and the return air." "How do you ensure the system is operating efficiently and reliably during a preventative maintenance call? - CORRECT ANSWER Combustion test" "What controls should be tested during a preventive maintenance call? - CORRECT ANSWER The primary control and all limit controls to be sure they function properlyand shut off the burner if a problem develops" "NORA recommends that during a preventative maintenance call the oil tank be checked for: - CORRECT ANSWER Corrosion, leaks, and water" "How should you approach a service call? - CORRECT ANSWER systematically" "Reset Pressed -Nothing Happens. What should be checked? - CORRECT ANSWER Voltage, is primary control sensing flame, cad-cell leads might be crimped, F-F circuit might be shorted, control might be defective" "On a No Heat Call: You press the reset & the burner runs. What do you do? - CORRECT ANSWER Begin your testing routine, determine why it went off, make all necessary repairs to correct the problem and to keep it from re-occurring" "What is combustion? - CORRECT ANSWER rapid reaction of combustible material with oxygen involving the production of heat and light" "3 things needed for combustion? - CORRECT ANSWER oxygen, fuel, heat" "what 3 electrical components does the primary control operate? - CORRECT ANSWER burner motor, igniter and oil valve" "what does the burner motor drive? - CORRECT ANSWER fan and fuel unit" "what's the fuel units' function? - CORRECT ANSWER moves fuel from the tank, pressurizes it and delivers it to the nozzle, provides fast and complete cutoff of fuel on burner shutdown" "primary air - CORRECT ANSWER air that exits through the center opening" "secondary air - CORRECT ANSWER air that exits through the slots, causes the air to spin enabling the best mix of fuel and air" "tertiary air - CORRECT ANSWER Air that exits around the outside of the flame retention ring and blankets the fuel with air to ensure clean combustion." "what's the difference between fixed and adjustable heads? - CORRECT ANSWER fixed heads are attached and have a preset tertiary air opening. an adjustable head is attached to the nozzle assembly and is moved to change the tertiary air opening" "The key final adjustment for most burners is? - CORRECT ANSWER Combustion air" "dirt or lint build up on fan blades or air inlet will? - CORRECT ANSWER reduce the amount of combustion air" "burner fan blades need to be clean of debris to ensure what? - CORRECT ANSWER right amount of combustion air" "High static pressure burners have been developed to? - CORRECT ANSWER push products of combustion air through heat exchanger of high efficiency appliances" "can cast iron fittings be used on an oil tank piping? - CORRECT ANSWER NO" "A tank without a functioning vent alarm should? - CORRECT ANSWER Not be filled until the vent alarm is repaired or replaced." "Tanks should be kept free of water because? - CORRECT ANSWER can lead to corrosion and bacteria growth" "how can condensation be reduced in outdoor tanks? - CORRECT ANSWER additives, putting it in an enclosure, or by painting it a lighter color" "for residential use, what size oil line is recommended? - CORRECT ANSWER 1/2" O.D or 3/8" I.D" "Fuel lines that contact concrete or dirt must be? - CORRECT ANSWER sleeved or coated" "In general; the right size tank is one that holds? - CORRECT ANSWER About one-third (1/3) of the customers annual fuel consumption." "T or F. Nora recommends pumping "clean" oil from an old tank into a new tank is ok. - CORRECT ANSWER False, NEVER OK" "burner air tube should be installed how? - CORRECT ANSWER 1/4" back from the inside wall of the combustion chamber" "Nozzle after-drip can be caused by? - CORRECT ANSWER bad check valve, air in nozzle, old unit hard brick chamber." "Fuel must burn completely in suspension without touching what? - CORRECT ANSWER any part of combustion chamber crown sheet, floor or walls" "T or F, ideally combustion chambers should be designed to both heat up and cool off quickly: - CORRECT ANSWER True" "If a chamber is too small, or the nozzle is too close to the chamber floor there will be? - CORRECT ANSWER impingement" "With no insulating material between the heat exchanger and the hot flue gasses, heat transfer to the water is: - CORRECT ANSWER better" "what is the purpose of the venting system? - CORRECT ANSWER Removes combustion gases safely to outside" "thermal draft is created when? - CORRECT ANSWER air in chimney is hotter than outside" "what types of draft and venting can be found on appliances? - CORRECT ANSWER direct vent, natural draft, induced draft, power venter" "If draft over the fire (norm = -01 to -.02"W.C.) is significantly lower than at the breech the unit may be: - CORRECT ANSWER have air leaks, plugged heat exchanger or overfiring" "where most important measurement of draft is? - CORRECT ANSWER over the fire" "why is a draft regulator required with chimney vented appliances? - CORRECT ANSWER draft produced by chimney variable and need to be maintained" "what are the 4 most common requirements when installing new flue pipe? - CORRECT ANSWER installed 18" from any combustibles, 1/4" per ft pitch, 3 screws and properly supported" "When two appliances are connected together (common vented) into the same chimney opening, the pipes should be joined using a ________ connector? - CORRECT ANSWER Y" "If 2 openings are provided into 1 chimney flue, they shall be at different levels, what appliance would be at the higher level? - CORRECT ANSWER The appliance with the lower firing rate shall enter at the higher level." "what is 1 cause of insufficient air for combustion? - CORRECT ANSWER less air leaks (infiltration)" "what's the best solution for insufficient combustion air? - CORRECT ANSWER outside air, isolated combustion air" "T or F, a draft regulator can increase the draft from the chimney or power venter - CORRECT ANSWER False, can only decrease" "which factors cause variable draft and require draft regulators to maintain a steady draft? - CORRECT ANSWER Humidity, Barometric Pressure, Air Temperatures." "natural draft is divided into two categories, what are they? - CORRECT ANSWER Thermal and Currential." "Draft for a direct vented appliance is produced by? - CORRECT ANSWER Static pressure produced by burner fan" "Outdoor Make-up air for combustion is required when there is less than________ cubic feet per 1000 BTU's? - CORRECT ANSWER 50" "Air is approximately ___% oxygen and ___ % nitrogen - CORRECT ANSWER 21% oxygen 78% nitrogen 1% trace" "#2 fuel is approximately___ % carbon? - CORRECT ANSWER 85% Carbon" "In an energized 120 VAC circuit, when a voltmeters leads are placed on both sides of a toggle switch in the closed position, the reading will be? - CORRECT ANSWER 0" "Electrical "current" describes the amount or rate of electricity flowing through a circuit, and it is measured in? - CORRECT ANSWER amps" "A clamp on ammeter converts? - CORRECT ANSWER strength oh magnetic field around wire turns to amp rating" "materials that offer very little resistance to flow of current are called? - CORRECT ANSWER conductors" "what is a good insulator at 120v but is a good conductor at 10,000v? - CORRECT ANSWER air" "when measuring resistance to flow in an electrical circuit, set the meter to the ___ scale - CORRECT ANSWER ohm" "Ohmmeters provide their own power, when testing continuity be sure the device is: - CORRECT ANSWER Isolated from its power source and capacitors are discharged." "an electrical load is a device which converts electrical energy into? - CORRECT ANSWER some other form of energy"