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OFTEC Oil Firing (OFT101/105E) study materials
OFTEC Oil Firing (OFT101/105E) study resources

OFTEC Oil Firing (OFT101/105E) practice questions

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Question 1Health and Safety, Legislation and Industry Standards

Under the Health and Safety at Work etc. Act 1974, which duty is placed on employees?

  1. To take reasonable care of themselves and others affected by their work Correct answer.
  2. To report all near misses to the Health and Safety Executive
  3. To provide all necessary personal protective equipment free of charge
  4. To prepare a written risk assessment for every task

Explanation

The Act places a general duty on employees to take reasonable care of themselves and of other persons who may be affected by their acts or omissions at work, and to cooperate with their employer on health and safety matters. Providing PPE and preparing risk assessments are employer duties, and near-miss reporting normally goes to the employer rather than the HSE.

Question 2Health and Safety, Legislation and Industry Standards

Which legislation requires employers to carry out a suitable and sufficient assessment of risks to workers?

  1. The Management of Health and Safety at Work Regulations 1999 Correct answer.
  2. The Provision and Use of Work Equipment Regulations 1998
  3. The Control of Substances Hazardous to Health Regulations 2002
  4. The Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013

Explanation

The Management of Health and Safety at Work Regulations 1999 impose the general duty to make a suitable and sufficient risk assessment. The other regulations impose more specific duties such as substance control, work equipment suitability, and incident reporting.

Question 3Health and Safety, Legislation and Industry Standards

An oil-fired appliance is being installed in a garage that forms part of a domestic dwelling. Which document should the technician consult first for the ventilation and flueing requirements?

  1. The local water authority's bye-laws
  2. The current edition of the relevant Building Regulations and associated approved guidance Correct answer.
  3. The manufacturer's boiler warranty terms
  4. The electricity at work regulations guidance notes

Explanation

Building Regulations, together with their approved documents and recognised competent person guidance, set the legal requirements for ventilation and flueing of combustion appliances in dwellings. Manufacturer's instructions supplement but do not replace these statutory requirements.

Question 4Health and Safety, Legislation and Industry Standards

Which of the following is a specified injury reportable to the enforcing authority under RIDDOR when it arises from a work activity?

  1. A minor cut requiring a plaster
  2. Bruising to the forearm from a knock
  3. A fracture, other than to fingers, thumbs or toes Correct answer.
  4. A sprained ankle that keeps the worker off normal duties for two days

Explanation

RIDDOR specifies certain fractures, other than to fingers, thumbs or toes, as reportable injuries. Minor injuries and short-term absences below the over-seven-day threshold are recorded but not reported as specified injuries.

Question 5Health and Safety, Legislation and Industry Standards

Before working on an oil-fired appliance, which isolation step best demonstrates compliance with safe isolation practice?

  1. Asking the householder to keep the boiler switched off while work proceeds
  2. Turning the room thermostat down to its minimum setting
  3. Removing the boiler fuse and leaving it on the workbench
  4. Switching off at the appliance control and locking off the electrical supply with a personal padlock Correct answer.

Explanation

Safe isolation requires positively isolating the supply, proving it dead, and securing the isolation with a personal lock and warning notice so it cannot be re-energised by others. Relying on others or leaving components loose does not provide secure isolation.

Question 6Health and Safety, Legislation and Industry Standards

What is the primary purpose of a CO2 fire extinguisher in an oil-fired plant room?

  1. To extinguish flammable liquid and electrical fires by smothering Correct answer.
  2. To provide a protective blanket for personnel escaping through flame
  3. To chemically neutralise burning oil into harmless compounds
  4. To cool burning solid materials such as wood and paper

Explanation

CO2 extinguishers work by displacing oxygen and are suitable for flammable liquid and live electrical equipment fires (Class B and electrical). They do not cool solids effectively and do not chemically neutralise fuel.

Question 7Health and Safety, Legislation and Industry Standards

A technician discovers a leaking oil line in a domestic property. Which immediate action best reflects the environmental duty of care?

  1. Contain the spill, stop the source and dispose of contaminated material through a licensed waste route Correct answer.
  2. Cover the spill with soil and leave it in place
  3. Wash the spill into the nearest surface water drain to dilute it
  4. Leave the leak until the next scheduled service visit

Explanation

Under environmental protection and waste duty of care rules, spills must be contained, the source stopped, and contaminated materials disposed of via a licensed carrier with proper documentation. Diluting to drains or leaving the leak causes pollution and breaches the duty of care.

Question 8Health and Safety, Legislation and Industry Standards

Which document must accompany oil when it is transferred as waste from a service visit?

  1. A gas safety record
  2. A boiler commissioning certificate
  3. A waste transfer note describing the waste and signed by both parties Correct answer.
  4. A material safety data sheet for the boiler

Explanation

The waste duty of care requires a written description of the waste (a waste transfer note) that is signed by the producer and the carrier, ensuring the waste is only handed to an authorised person. Commissioning certificates and safety records serve different purposes.

Question 9Health and Safety, Legislation and Industry Standards

A technician is asked to work alone on a roof to service a flue terminal. Which legal requirement is most directly engaged?

  1. The Work at Height Regulations 2005 require avoidance of work at height where reasonably practicable Correct answer.
  2. The Electricity at Work Regulations require a permit to work on roofs
  3. The COSHH Regulations require air monitoring at the terminal
  4. The Pressure Systems Safety Regulations require written schemes for flues

Explanation

The Work at Height Regulations require duty holders to avoid work at height where reasonably practicable, and where it cannot be avoided, to prevent falls through suitable measures. The other regulations address different hazards and do not specifically govern roof access.

Question 10Health and Safety, Legislation and Industry Standards

Which of the following best describes the purpose of a permit to work system in an oil tanker delivery or plant room task?

  1. To formally authorise and control high-risk work with defined precautions and sign-off Correct answer.
  2. To replace the need for a risk assessment
  3. To record the price of oil delivered to the customer
  4. To certify the boiler's combustion efficiency

Explanation

A permit to work is a formal control for high-risk activities, specifying precautions, authorisation and hand-back signatures. It supplements rather than replaces risk assessment and has nothing to do with pricing or efficiency certification.

Question 11Health and Safety, Legislation and Industry Standards

Which item of personal protective equipment is most important when handling kerosene during a service?

  1. Chemical-resistant gloves and eye protection Correct answer.
  2. Steel-toe boots only
  3. Hearing protection
  4. A high-visibility vest

Explanation

Kerosene is a skin and eye irritant, so chemical-resistant gloves and eye protection are the key controls for handling it. Footwear, high-visibility clothing and hearing protection address other hazards and do not protect against dermal or ocular contact.

Question 12Health and Safety, Legislation and Industry Standards

Which regulation places a duty on employers to ensure that work equipment is suitable for its intended use and maintained in an efficient state?

  1. The Health and Safety (First-Aid) Regulations 1981
  2. The Personal Protective Equipment at Work Regulations 1992
  3. The Manual Handling Operations Regulations 1992
  4. The Provision and Use of Work Equipment Regulations 1998 Correct answer.

Explanation

PUWER requires work equipment to be suitable for purpose, maintained in efficient working order and inspected where necessary. The other regulations address manual handling, PPE and first aid respectively.

Question 13Health and Safety, Legislation and Industry Standards

An engineer notices a smell of kerosene in a basement plant room and a stained floor. What is the correct sequence of actions?

  1. Start the boiler to check whether it still runs
  2. Evacuate and ventilate, eliminate ignition sources, isolate the fuel supply, then investigate Correct answer.
  3. Light a match to locate the leak by flame
  4. Mop the floor into a bucket and continue the service

Explanation

A suspected fuel leak in a confined space creates fire and fume risk, so the priority is to remove people, ventilate, remove ignition sources and isolate the supply before investigating. Introducing flames or running the appliance risks ignition, and mopping without isolation ignores the ongoing hazard.

Question 14Health and Safety, Legislation and Industry Standards

Which body is responsible for enforcing health and safety law in most domestic and commercial premises where oil-fired appliances are installed?

  1. The Environment Agency
  2. The appliance manufacturer
  3. The water undertaker
  4. The local authority or the Health and Safety Executive depending on the premises type Correct answer.

Explanation

Enforcement of health and safety law is split between local authorities (typically for shops, offices and leisure premises) and the HSE for other premises. The Environment Agency, water undertakers and manufacturers do not enforce the Health and Safety at Work etc. Act.

Question 15Health and Safety, Legislation and Industry Standards

A technician uses a ladder as a work platform for a task lasting around an hour at height. Which statement reflects the Work at Height Regulations?

  1. Ladders are prohibited for all work at height
  2. Ladders are acceptable for any duration provided the user is trained
  3. Ladders may be used only if a permit to work is issued
  4. A ladder may be used where a risk assessment shows it is the most suitable option for low-risk, short-duration work Correct answer.

Explanation

The Regulations allow ladders for low-risk, short-duration tasks where a risk assessment justifies them as reasonably practicable, with measures to prevent falls. They are not banned, but neither is training alone sufficient for unlimited use.

Question 16Health and Safety, Legislation and Industry Standards

Which of the following is a key requirement of the Control of Substances Hazardous to Health Regulations when using a solvent-based cleaner?

  1. Register the solvent with the local water authority
  2. Assess exposure, prevent or adequately control it, and provide health surveillance where required Correct answer.
  3. Notify the fire brigade before each use
  4. Obtain a boiler efficiency certificate before use

Explanation

COSHH requires a suitable and sufficient assessment of health risk, prevention or adequate control of exposure, and health surveillance where the assessment shows it is appropriate. Registration with water authorities or fire brigade notification is not a COSHH requirement.

Question 17Health and Safety, Legislation and Industry Standards

An installer is unsure whether a proposed flue termination position complies with the applicable standard. Which course of action best meets professional and legal obligations?

  1. Ask the householder to sign a disclaimer and install as planned
  2. Check the current edition of the relevant standard and manufacturer's instructions before proceeding Correct answer.
  3. Proceed using a position remembered from an older edition of the standard
  4. Install it and correct any problem at the next service

Explanation

Compliance depends on the current edition of the applicable standard and the manufacturer's instructions, and work must not proceed on out-of-date or assumed information. Relying on a disclaimer or deferring correction does not discharge the legal duty.

Question 18Health and Safety, Legislation and Industry Standards

A technician is asked to sign off an installation that they did not personally commission or inspect. What is the most appropriate response?

  1. Sign it and note on the certificate that it was not inspected
  2. Sign it because the installing engineer is competent
  3. Sign it after a phone call with the installer
  4. Decline to certify work not personally verified, as certification must reflect the signatory's own inspection Correct answer.

Explanation

Certification is a declaration that the signatory has inspected and verified the work, so signing work not personally checked is a false declaration regardless of the installer's competence. A telephone assurance or a caveat does not substitute for inspection.

Question 19Health and Safety, Legislation and Industry Standards

Which of the following best describes the legal status of a manufacturer's installation instructions for an oil-fired appliance?

  1. They are advisory only and may be disregarded at will
  2. They are enforceable only if the appliance is under warranty
  3. They must be followed to comply with the applicable regulations and to maintain the appliance's approval Correct answer.
  4. They apply only to the first year after manufacture

Explanation

Manufacturer's instructions are integral to demonstrating compliance with Building Regulations and product approval, and deviation can invalidate the installation's compliance. They are not merely advisory, time-limited or warranty-dependent.

Question 20Health and Safety, Legislation and Industry Standards

Which combination of records best demonstrates compliance with the waste duty of care after replacing an oil filter?

  1. A verbal agreement with a scrap collector
  2. A photograph of the filter in the van
  3. A signed waste transfer note naming an authorised carrier and a description of the waste Correct answer.
  4. A note in the service log that the filter was removed

Explanation

The duty of care requires waste to be described in writing and transferred only to an authorised person, evidenced by a signed transfer note. Photographs, verbal agreements and service log notes do not provide the required legal record.

Question 21Oil Storage, Supply and Fuel Properties

Which British Standard specifies the requirements for kerosene (Class C2) heating oil?

  1. BS EN 14214
  2. BS 2869 Part 1
  3. BS 2869 Part 2 Correct answer.
  4. BS EN 590

Explanation

BS 2869 covers fuel oils for non-automotive use and is split into parts; Part 2 addresses gas oils and kerosene for heating, including Class C2 kerosene. BS EN 590 is the automotive diesel standard, and BS EN 14214 is for biodiesel.

Question 22Oil Storage, Supply and Fuel Properties

Gas oil for heating installations in the UK is identified by which colour and marker combination?

  1. Blue with a solvent yellow marker
  2. Green with a quinizarin marker Correct answer.
  3. Clear with no marker
  4. Red with a furfural marker

Explanation

Heating gas oil is dyed green and marked with quinizarin (Solvent Yellow 124) to distinguish rebated fuel from duty-paid road diesel. Red dye is associated with marked gas oil for off-road machinery.

Question 23Oil Storage, Supply and Fuel Properties

What is the approximate flash point of standard Class C2 kerosene heating oil?

  1. About 38 degrees C
  2. About 55 degrees C Correct answer.
  3. About 100 degrees C
  4. About 150 degrees C

Explanation

Kerosene heating oil has a closed-cup flash point of around 55 degrees C, well above the 38 degrees C minimum applied to gas oil. This higher flash point makes kerosene safer to store in domestic tanks.

Question 24Oil Storage, Supply and Fuel Properties

A domestic oil tank is being sited on a concrete base. What is the minimum recommended distance from a boundary or non-fire-rated structure for a tank up to 3500 litres?

  1. 0.6 metres
  2. 1.8 metres Correct answer.
  3. 6 metres
  4. 3.5 metres

Explanation

Building regulations guidance requires a separation of at least 1.8 metres from a boundary or non-fire-rated building for tanks up to 3500 litres. Smaller distances may be permitted with fire-rated construction.

Question 25Oil Storage, Supply and Fuel Properties

Which material is acceptable as the base for a single-skinned plastic domestic oil tank?

  1. Timber decking
  2. Loose sand
  3. A paved slab of suitable load-bearing construction Correct answer.
  4. Compacted gravel

Explanation

Tanks must stand on a level, load-bearing base such as a concrete or paved slab capable of supporting the full weight of the filled tank. Loose or uneven materials can cause the tank to distort and fail.

Question 26Oil Storage, Supply and Fuel Properties

Why must an oil storage tank be fitted with a vent pipe terminating in the open air?

  1. To allow the tank to be filled more quickly
  2. To let water drain out of the tank
  3. To prevent pressure or vacuum building during filling and draw-off Correct answer.
  4. To provide a point for sampling the fuel

Explanation

The vent equalises pressure as fuel is delivered or drawn, preventing tank distortion or backflow. It must terminate safely outside so displaced vapours disperse.

Question 27Oil Storage, Supply and Fuel Properties

A bunded tank is required in which situation?

  1. Only when kerosene is stored
  2. When the tank is near a drain, watercourse or in a location where a spill could escape Correct answer.
  3. Only when the tank exceeds 10000 litres
  4. Only when the tank is indoors

Explanation

Bunding is required where a leak could reach a drain, watercourse or other sensitive location, and for tanks above certain volumes. The bund must hold at least 110 percent of the tank capacity.

Question 28Oil Storage, Supply and Fuel Properties

What minimum capacity should an oil tank bund have relative to the tank it surrounds?

  1. 150 percent of tank capacity
  2. 100 percent of tank capacity
  3. 110 percent of tank capacity Correct answer.
  4. 50 percent of tank capacity

Explanation

A bund must contain at least 110 percent of the capacity of the largest tank it encloses. This allows for the displaced volume of the tank itself plus a margin for rainfall or spillage.

Question 29Oil Storage, Supply and Fuel Properties

Which component prevents oil flowing back to the tank when the burner is not running?

  1. Non-return valve Correct answer.
  2. Fire valve
  3. Pressure reducing valve
  4. Filter

Explanation

A non-return valve allows fuel to flow one way only, preventing oil draining back or siphoning when the pump stops. The fire valve shuts off supply in an emergency, and the filter removes contaminants.

Question 30Oil Storage, Supply and Fuel Properties

A single-pipe gravity supply to an oil burner relies on which principle?

  1. A pump drawing fuel under vacuum
  2. Capillary action in the pipe
  3. Oil flowing from the tank by gravity above the burner Correct answer.
  4. Pressure from a pressurised tank

Explanation

In a gravity feed the tank is positioned above the burner so oil flows by gravity to the burner pump. Two-pipe systems instead use the pump to draw fuel under vacuum.

Question 31Oil Storage, Supply and Fuel Properties

What is the main purpose of a fire valve in an oil supply line?

  1. To filter out water from the fuel
  2. To shut off the oil supply if the temperature exceeds a set limit Correct answer.
  3. To measure the quantity of oil drawn
  4. To regulate fuel pressure at the burner

Explanation

A fire valve incorporates a temperature-sensitive element that closes the oil supply when it detects excessive heat, cutting fuel to a fire. It is positioned remotely from the burner with its sensing element near the appliance.

Question 32Oil Storage, Supply and Fuel Properties

Where should the sensing element of a remote-acting fire valve be located?

  1. Inside the oil tank
  2. In the boiler casing above the burner Correct answer.
  3. Outside the building at the vent
  4. At the tank outlet valve

Explanation

The sensing element is mounted above or near the burner within the appliance casing so it detects overheating at the source. The valve body itself sits on the supply line remote from the appliance.

Question 33Oil Storage, Supply and Fuel Properties

What does a two-pipe oil supply system use the second pipe for?

  1. To supply a second appliance
  2. To return surplus oil to the tank Correct answer.
  3. To vent the tank
  4. To drain water from the filter

Explanation

In a two-pipe system the pump draws oil through the supply line and returns surplus fuel to the tank via the return line. This suits installations where the tank is below the burner.

Question 34Oil Storage, Supply and Fuel Properties

Which fuel property most directly affects the ease of pumping oil in cold weather?

  1. Cloud point Correct answer.
  2. Sulphur content
  3. Calorific value
  4. Ash content

Explanation

Cloud point is the temperature at which wax crystals begin to form, which can block filters and pipes. A low cloud point means the fuel remains pumpable at lower temperatures.

Question 35Oil Storage, Supply and Fuel Properties

Why is water contamination particularly damaging in a stored oil tank?

  1. It raises the calorific value of the fuel
  2. It improves fuel atomisation
  3. It makes the fuel more flammable
  4. It promotes corrosion and can cause burner flame failure Correct answer.

Explanation

Water is denser than oil and collects at the tank bottom, causing corrosion and being drawn into the burner where it can extinguish the flame or damage the pump. Regular water removal and good tank design reduce this risk.

Question 36Oil Storage, Supply and Fuel Properties

What is the typical maximum sulphur content permitted for Class A2 gas oil under BS 2869?

  1. 0.001 percent (10 mg/kg)
  2. 1.0 percent (10000 mg/kg)
  3. 0.1 percent (1000 mg/kg) Correct answer.
  4. 0.5 percent (5000 mg/kg)

Explanation

BS 2869 gas oil for heating is limited to a low sulphur content, typically 0.1 percent (1000 mg/kg) for the standard grade. Lower sulphur grades are also available for sensitive applications.

Question 37Oil Storage, Supply and Fuel Properties

An oil tank is to be installed where the top of the tank is below the level of the burner. Which supply arrangement is appropriate?

  1. A two-pipe pumped system with a non-return valve Correct answer.
  2. A syphon feed with no pump
  3. A vented header tank
  4. A gravity single-pipe feed

Explanation

When the tank is below the burner, oil must be drawn by the pump, so a two-pipe system with a non-return valve is used to prevent drain-back. Gravity feed requires the tank outlet above the burner.

Question 38Oil Storage, Supply and Fuel Properties

A bunded tank shows an accumulation of oil within the bund. What is the correct interpretation?

  1. The inner tank or its fittings are leaking and require investigation Correct answer.
  2. The bund is functioning normally and needs no action
  3. The bund is overfilled with rainwater only
  4. The tank has been overfilled deliberately

Explanation

Oil in the bund indicates a leak from the inner tank, its outlet, or associated pipework, which must be investigated and repaired immediately. The bund has contained the spill, but the source must be found.

Question 39Oil Storage, Supply and Fuel Properties

What is the purpose of a tank contents gauge?

  1. To indicate the quantity of oil remaining in the tank Correct answer.
  2. To measure fuel temperature
  3. To control the burner firing rate
  4. To filter the oil

Explanation

A contents gauge allows the user to check how much fuel remains so the tank can be refilled before running dry. It does not affect combustion or filtration.

Question 40Oil Storage, Supply and Fuel Properties

Which grade of BS 2869 fuel oil is a residual (heavy) fuel oil rather than a distillate?

  1. Class B1 gas oil
  2. Class A2 gas oil
  3. Class D heavy fuel oil Correct answer.
  4. Class C2 kerosene

Explanation

Class D fuels are residual heavy fuel oils used in larger commercial and industrial plant. Classes A2, B1 and C2 are distillate fuels.

Question 41Oil Storage, Supply and Fuel Properties

Why should an oil supply pipe be protected against frost where it runs externally?

  1. To reduce the risk of theft
  2. To prevent the oil freezing solid and blocking the line Correct answer.
  3. To improve fuel flow rate
  4. To stop the pipe expanding and bursting

Explanation

Exposed pipework can allow wax formation or, in extreme cold, freezing that blocks the supply. Insulation and frost protection keep the fuel flowing, particularly for kerosene in exposed runs.

Question 42Oil Storage, Supply and Fuel Properties

A tank is fitted with an overfill prevention device. What is its function?

  1. To measure the fuel's calorific value
  2. To warn or stop delivery before the tank overflows Correct answer.
  3. To filter the incoming fuel
  4. To increase the tank's storage capacity

Explanation

An overfill prevention device alerts the delivery driver or stops the fill before the tank overflows, reducing spill risk. It works with the contents gauge and fill point.

Question 43Oil Storage, Supply and Fuel Properties

In a gravity-fed system, what does the head of oil between the tank outlet and the burner affect?

  1. The colour of the flame
  2. The sulphur content of the fuel
  3. The flash point of the fuel
  4. The supply pressure available at the burner Correct answer.

Explanation

In a gravity system the vertical height (head) between the tank outlet and the burner determines the static pressure available at the burner. Excessive head can cause over-pressure and must be controlled.

Question 44Oil Storage, Supply and Fuel Properties

What is the recommended practice for supporting an external oil supply pipe?

  1. Allow it to rest on the ground
  2. Suspend it from the tank vent
  3. Support it at regular intervals with suitable clips Correct answer.
  4. Tie it to the bund wall

Explanation

Pipework should be clipped and supported at regular intervals to prevent sagging, stress and damage, and to keep it clear of the ground. Proper support also protects joints from strain.

Question 45Oil Fired Appliances: Types, Construction and Operation

In a pressure-jet oil burner, what is the primary function of the nozzle?

  1. To filter solid particles from the incoming oil supply
  2. To ignite the fuel-air mixture at start-up
  3. To atomise the fuel into a fine spray for efficient combustion Correct answer.
  4. To regulate the temperature of the combustion air

Explanation

The pressure-jet nozzle forces oil through a small orifice under pressure, breaking it into fine droplets. Good atomisation increases surface area so the oil vapourises and mixes with air for clean combustion.

Question 46Oil Fired Appliances: Types, Construction and Operation

What does the nozzle 'spray angle' (pattern angle) primarily determine in a pressure-jet burner?

  1. The pressure setting of the fuel pump
  2. The shape of the flame and how it matches the combustion chamber Correct answer.
  3. The viscosity of the oil at the nozzle tip
  4. The electrical resistance of the ignition electrodes

Explanation

The spray angle controls the cone shape of the atomised oil, which must suit the combustion chamber geometry to avoid impingement on walls or short-circuiting. A mismatched angle causes poor flame shape and sooting.

Question 47Oil Fired Appliances: Types, Construction and Operation

A nozzle rated 0.60 USgal/h at 100 psi is operated at 100 psi. What does the rating represent?

  1. The nominal fuel throughput at the stated pressure Correct answer.
  2. The combustion air flow required
  3. The volume of oil atomised per minute
  4. The maximum pump delivery pressure

Explanation

Nozzle ratings are expressed as nominal flow in US gallons per hour at a stated reference pressure (commonly 100 psi). Actual flow varies with the square root of pressure, so the rating applies only at the reference pressure.

Question 48Oil Fired Appliances: Types, Construction and Operation

Why do many pressure-jet nozzles incorporate a sintered filter immediately upstream of the swirl chamber?

  1. To increase the oil pressure at the tip
  2. To cool the nozzle body during operation
  3. To measure the oil flow rate
  4. To prevent small particles blocking the fine orifice Correct answer.

Explanation

The orifice and swirl slots are very small, so tiny particles can block or distort the spray. The integral filter traps debris close to the tip to protect the fine passages.

Question 49Oil Fired Appliances: Types, Construction and Operation

In a conventional vaporising (pot) burner, how is the oil primarily prepared for combustion?

  1. It is forced through a fine orifice at high pressure
  2. It is heated in a bowl or pot so it vapourises before mixing with air Correct answer.
  3. It is electrically charged and attracted to a grid
  4. It is pre-mixed with air in a venturi before ignition

Explanation

Vaporising burners deliver oil to a heated pot or bowl where it evaporates; the vapour then mixes with secondary air and burns. They operate at low pressure and rely on heat rather than high-pressure atomisation.

Question 50Oil Fired Appliances: Types, Construction and Operation

A blue flame with a yellow tip appearing on an oil burner most likely indicates:

  1. The nozzle is too small for the appliance
  2. Excess combustion air across the whole flame
  3. The oil is too cold to ignite
  4. Incomplete combustion or secondary air issues at the flame tip Correct answer.

Explanation

A yellow luminous tip suggests incomplete combustion or localised air deficiency at the flame end, often from incorrect air settings, a fouled nozzle or a mismatched spray pattern. A clean flame should be predominantly blue.