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Oil burner test
What is the largest exposed tank allowed in a building without a permit - Answer- 660 g What is tank approval - Answer- UL 80 UL 142 A supply tank shall be securely supported by ridged, non-combustible supports to prevent settling, sliding or lifting. true or false - Answer- True What is the largest amount of oil that can be stored with exposed tanks? - Answer- 1320 g What is the closest distance a supply tank can be to the burner - Answer- 5 ft What is the gauge of a 275 g above ground tank - Answer- 12 gauge The maximum amount of fuel may be delivered without a permit to store in effect provided that application has been made in accordance with code. true or false - Answer- True Vent pipe for a 500 g tank should be - Answer- 1 1/4" A supply tank may be supported by any ridge support. true or false - Answer- False Stack switch relays can no longer be used in installations or replacement because - Answer- Their lock-out time is no longer the code requirement An oil safety valve should be used when burner pump is lifting oil. True or false - Answer- False On a warm air furnace, the blower comes off and on in short cycles because - Answer- The fan on/off differential is less than 40°F What could cause a steam boiler to flood - Answer- Leaky tank less coil Having to put water in a steam boiler once or twice a week is caused by - Answer- Weak return line, radiator vents leaking, boiler sprung a leak Some radiators on a steam system do not heat up because - Answer- The radiator vents are clogged
On a hot water boiler the pressure is 30psi and the relief valve is open because - Answer- Leaky tankless coil, bad pressure reducing valve, perforated tankless bladder Some forced hot-water radiators are not heating because - Answer- Vent is clogged, radiators are air bound, radiator valves clogged shut A cad-cell primary control can lock-out safety because - Answer- Cad-cell is dirty, Cad- cell is faulty, The cad-cell is not sensing flame On a no heat call, a cad-cell primary control fired when TT is jumped out because - Answer- The thermostat or thermostat wired are no good In-step means - Answer- The primary control start circuit is closed On a no heat call on a hot water system, the oil burner is off on high-limit, but the circulator is not running because - Answer- The reverse is open, circulator motor burnt out, switching relay is faulty The burner operates but there is no combustion because - Answer- There is too much air On a replacement steam boiler installation, you should pipe full-size risers to the header. True or false - Answer- False What is the best way to remove surface oil? - Answer- Skimming Where should the water like normally be in the sight glass when the boiler is off - Answer- Center of the sight glass What is the purpose of the automatic water feed on a steam boiler - Answer- To maintain a safe minimum water line What is the purpose of the hartford loop - Answer- To prevent siphoning of the boiler What is the normal cut in pressure of a residential steam boiler - Answer- 1/2 psi What is the purpose of an oil safety valve - Answer- Prevents oil flow in the event of a line rupture or excessive line inlet pressure What does the term "approved" mean - Answer- Recognized by a nationally recognized texting lab What is a safety control - Answer- Any control used to prevent unsafe operation of the uncontrolled equipment
An approved combustion air supervisory switch is required when - Answer- When a separately powered louvers fan or blower is used to supply combustion air for the oil burner When does a steam boiler need a low water cutoff - Answer- Always When does a hot water boiler need a low water cutoff - Answer- Over 400,000 BTU's If a second oil-fired appliance is added to an existing installation it must - Answer- Install it on its own separate circuit from the electrical panel and must be installed by a licensed electrician Must oil burner circuits be installed in compliance with both the Massachusetts electrical and oil burner controls? True or false - Answer- True A thermal switch that must be located not more than 6 feet above the oil burner is rated at what temperature - Answer- 165 degrees At what height is a second thermal switch required - Answer- 12 feet above burner or appliance What three parts are required for a power vent system - Answer- Power vent, air pressure switch, and post purge control The minimum distance a power vent may terminate above the finish grade is - Answer- One foot The minimum distance a power vent may terminate from a door, window, or gravity air intake is - Answer- 4 feet When a separate power venter and hood are used, the power venter shall be located - Answer- As close to the hood as possible The power venter shall be sized to accordance with - Answer- Maximum input capacity of the appliance An oil soaked combustion chamber may be cleared by what method - Answer- There is no method of cleaning an oil soaked chamber, it must be removed The first rule that should be observed when responding to a no combustion call is - Answer- Inspect the chamber to insure that the combustion chamber is not soaked On a fuel line used with an oil safety valve, air presence in the fuel pump may be an indication of - Answer- An air leak in the line The best way to test an oil safety valve is - Answer- Vacuum test the line
The best way to test the performance of a fuel pump is to - Answer- Perform both vacuum and pressure tests on the pump Soot deposits on a power vented appliance may indicate - Answer- Insufficient combustion air in the boiler room The cross connection between two supply tanks shall not exceed - Answer- 660 g When is the automatic draft control not required - Answer- When the equipment is so designed to control the draft Combustion performance testing can indicate - Answer- Improper air oil mixture, too much combustion air, low pump pressure If a second oil burning appliance is installed in a single chimney, you must insure - Answer- Sufficient draft is available for safe operation of all connected equipment Delayed ignition can be caused by - Answer- Weak ignition transformer You should replace the oil burner nozzle with - Answer- Manufacturers recommended nozzle spray pattern and spray angle Viscosity problems can be corrected by - Answer- Decreasing the nozzle size and increasing the pump pressure accordingly The minimum operating pressure of an oil pump is - Answer- 100psi If a stack type controller fails, you must - Answer- Replace it with an approved type controller Aquastats are normally found on what type of heating system - Answer- Hydronic Airstats are found on what type of heating system - Answer- Forced hot air Undersized returns on a warm air system can result in what - Answer- Short cycling of the oil burner Incorrect nozzle selection in regards to gallon per hour, can result in what problems in a steam system - Answer- Some radiators not heating quickly enough Low boiler water temperature in a hydronic hot water system may be caused by - Answer- Undersized oil burner nozzle Delayed opening oil valves are used to - Answer- Allow oil pump pressure come up to speed
One advantage of a two stage fuel unit on a one pipe system application is - Answer- There are no advantages If the vacuum gauge reading is substantially above the calculated reading with the burner running the cause could be - Answer- Restriction in supply line The flow rate stamped on the nozzle is based on what pressure - Answer- 100psi Increasing the fuel pump pressure will - Answer- Increase the flow rate High viscosity problems brought on by cold oil may be minimized by - Answer- Increasing pump pressure and reducing nozzle size, installing a nozzle line heater, blend with kerosene or fuel additives Before installing a new nozzle the technician should - Answer- Flush out the nozzle line and adapter What is the single biggest cause of low oil burner efficiency - Answer- Poor mix of air and oil What new technology makes power vent and direct vent work more reliably - Answer- Pre and post purge primary controls When combustion testing with an electronic analyzer you must first - Answer- Perform a smoke test to be sure you are burning at a zero trace smoke Assuming that you have a properly sized nozzle, which of the following is not a cause for smoke and soot - Answer- Fuel pump pressure is set over 120psi What must be done to a draft gauge before use? - Answer- Zero out the scale When using a pump type smoke tester, ten full strokes are necessary to - Answer- Draw the proper amount of flue gas through the paper A CO2 reading of 7% at the breach and 10% over the fire indicates - Answer- Excess air leaks into the furnace or boiler Increasing the air input to clean up the fire will also increase - Answer- Flue gas temperature In order to calculate the steady state efficiency we need the following two pieces of information - Answer- The net stack temperature and either the % of CO2 or O The holes that are provided in the flue pipe for combustion testing must be - Answer- As close to the appliance as possible
The amount of electricity that flows in a wire is measured in - Answer- Amperes The flow of electricity in a circuit is opposed by - Answer- Resistance Materials whose electrons are so loosely bound that they can be persuaded to move with very little pressure allowing electricity to flow are called - Answer- Conductors A thing that uses electricity to perform useful worn is called - Answer- A load What do you do if the secondary voltage from a transformer is too low - Answer- Check the primary voltage In a series circuit there is - Answer- Only one path for current Residential burner ignition systems normally operate at what primary voltage - Answer- 120 volts When an ignition transformer is only energized until the flame is established, it is called
- Answer- Interrupted ignition The ________ switch opens when a split phase motor has almost reached full speed - Answer- Centrifugal If a split phase burner motor does not operate after the primary control has been reset and the voltage to the motor is correct you should check - Answer- The overload switch PSC motors use a capacitor to release an electrical charge that helps get them started. Once they start - Answer- The capacitor and the auxiliary windings remain in circuit while the motor is running Any dirt or lint build up in the bevel of the burner fan blades will - Answer- Reduce the amount of combustion air, effect the cad cell, cause the pump seal to leak The control that shuts off the burner in the event of excessive temperature or pressure is a - Answer- High limit control A reverse acting aquastat is used in a hydronic system to - Answer- Stop the circulator when the boiler water temperature falls below a preset temperature In all oil powered residential heating systems the high limit must be - Answer- Line voltage and wired in series with the primary control The heat anticipator in the thermostat should be set to - Answer- The amperage draw of the control circuit that it is operating
Smoke, soot, or oil odor calls could be caused by the following - Answer- An attic fan dropping the house pressure below the outside air pressure A thermostat is located near a lamp, what affect if any would this have on the heating? - Answer- It would cause occasional erratic insufficient heat To check a cad cell, unhook both cell leads from FF, start the burner, jump the FF terminals, then measure the output from the cell leads as it views the flame. The reading should be - Answer- 1600 OHMS or less A minimum bet stack temperature of about 350 degrees must be maintained: - Answer- To avoid condensation and maintain draft Off cycle heat loss is created by air flow through the heat exchanger and up the chimney. What is NOT a factor in off-cycle losses - Answer- The oil pump pressure Flame retention burners have revolutionized our industry. They are more reliable, efficient, and cleaner burning then the older burners. What is NOT an advantage of flame retention? - Answer- Reduces jacket and piping losses What affect does higher viscosity have on the nozzle operation - Answer- Increases flow rate If the vacuum gauge reading is substantially above the calculated reading with the burner running, the cause could be: - Answer- Restriction in the supply line The purpose of the oil burner nozzle is to - Answer- Atomize, pattern, and meter the oil The draft regulator must be installed: - Answer- Always, except when the equipment is designed to otherwise control the draft How should an oil fired unit be connected to a chimney that has an existing gas fired water heater? - Answer- By cutting another hole in the chimney below the flue for the gas water heater Carbon monoxide is produced by - Answer- Incomplete combustion The holes that are provided in the flue pipe for combustion testing must be - Answer- As close to the heating unit as possible The maximum length of flexible metallic sheathing that can be used on an oil burner circuit is - Answer- Six feet The advantage of solid state ignitors over ignition transformers is - Answer- They are not as affected by voltage drops
The main function of the primary control is - Answer- Locking out on safety in the event of flame failure or non ignition The maximum pressure for a residential steam boiler is - Answer- 15 psi Normal cad cell operating resistance should be - Answer- 0 to 1000 ohms A confined space is defined as any space less than _____ cubic feet per 1000 BTU - Answer- 50 What is the purpose of an oil safety valve - Answer- Shut oil flow is the supply line develops a leak. Protect pump from input pressure exceeding 3 psi Where are permits obtained - Answer- Local fire dept
