Maintenance and Service Procedures
Introduction
Maintenance and service of oil heating systems are the core of the oil heating technician trade. The Red Seal exam assesses your ability to perform preventive and corrective maintenance procedures in accordance with national standards, while ensuring occupant safety and optimal equipment efficiency. This chapter covers essential procedures, maintenance intervals, adjustment calculations, and regulatory requirements applicable across Canada.
Maintenance Frequencies and Regulatory Requirements
Recommended Maintenance Intervals
Maintenance frequency depends on the type of equipment, fuel quality, and operating conditions. The Canadian Electrical Code, Part I (C22.1-21) and CSA B139 (Installation Code for Oil-Burning Equipment) establish the minimum requirements.
| Type of Equipment | Preventive Maintenance | Complete Inspection | Filter Replacement |
|---|
| Oil burner (residential) | Annual | Annual | Annual or as needed |
| Commercial/industrial burner | Semi-annual | Annual | Quarterly or as needed |
| Storage tank (underground) | Annual visual inspection | Leak test (per regulations) | N/A |
| Storage tank (aboveground) | Semi-annual visual inspection | Annual complete inspection | N/A |
| Flue pipe | Annual inspection | Cleaning as needed | N/A |
CSA B139 Requirements
CSA B139 (Installation and Maintenance of Oil-Burning Equipment) is the primary reference for maintenance procedures. Key requirements include:
Maintenance must be performed by a qualified technician.
Worn or defective parts must be replaced with equivalent CSA-certified parts.
Burner adjustments must be verified after any service intervention.
A maintenance record must be kept for each installation.
Any fuel leak must be corrected immediately.
Preventive Burner Maintenance Procedures
Initial Inspection and Preparation
Before beginning any maintenance procedure, you must:
18.Disconnect the electrical supply to the burner via the circuit breaker or service switch.
19.Close the shut-off valve on the oil supply line.
20.Check for visible leaks around the burner, pump, and fittings.
21.Protect the work area with drop cloths to prevent fuel stains.
22.Prepare tools and instruments: multimeter, pressure gauge, combustion analyzer, thermometer, wrenches, screwdrivers, etc.
Cleaning the Electrodes and Combustion Head
Electrodes must be cleaned and inspected at every annual maintenance visit. Carbon buildup on electrodes can cause ignition misfires and incomplete combustion.
Cleaning Procedure:
26.Remove the burner from the combustion chamber or open the access door.
27.Remove the electrode assembly and nozzle.
28.Clean the electrodes with a fine file or fine abrasive paper.
29.Check the electrode gap: typically 3.2 mm (1/8 in) for most burners, but always refer to manufacturer specifications.
30.Check electrode position relative to the nozzle: electrodes should be positioned 6.4 mm (1/4 in) above the nozzle plane, and 3.2 mm (1/8 in) from the nozzle center.
31.Replace electrodes if the porcelain is cracked or chipped.
Typical Electrode Spacing Table:
| Manufacturer | Gap (mm) | Distance to Nozzle (mm) |
|---|
| Beckett | 3.2 | 6.4 |
| Riello | 3.5 | 7.0 |
| Carlin | 3.2 | 6.4 |
| Wayne | 3.0 | 6.0 |
Nozzle Replacement
The nozzle must be replaced at every annual maintenance visit. A worn or clogged nozzle causes irregular spray patterns, incomplete combustion, and soot buildup.
Procedure:
37.Remove the old nozzle using a nozzle wrench (19 mm or 7/8 in).
38.Inspect the old nozzle: an irregular spray pattern indicates wear.
39.Install the new nozzle with the same flow rate and spray angle as specified by the manufacturer.
40.Tighten the nozzle by hand, then an additional quarter turn with the wrench. Do not overtighten.
41.Verify that the O-ring or nozzle seat is in good condition.
Nozzle Flow Rate Calculation:
The nozzle flow rating is expressed in US gallons per hour (USGPH). Burner output can be calculated as follows:
Output (BTU/h) = Flow Rate (USGPH) × 140,000 BTU/USG
For example, a 0.75 USGPH nozzle produces:
0.75 × 140,000 = 105,000 BTU/h
Pump Cleaning and Inspection
The burner pump must be inspected for leaks, abnormal noises, and discharge pressure.
Pump Pressure Check:
50.Install a pressure gauge on the pump pressure port (test port).
51.Start the burner and allow the pump to reach operating pressure.
52.Typical pressure is 100 to 150 psi (689 to 1034 kPa) depending on the manufacturer.
53.Compare the measured pressure to the specified value. Pressure that is too low indicates pump wear or a clogged filter.
54.Check the vacuum pressure on the suction side: it must not exceed 10 in Hg (34 kPa) for a two-pipe system.
Pump Vacuum Test:
Close the shut-off valve on the suction line.
Install a vacuum gauge on the vacuum port.
Start the burner and note the reading. A reading above 10 in Hg indicates a restriction in the suction line or a clogged filter.
Oil Filter Cleaning
The oil filter must be replaced at every annual maintenance visit. A clogged filter reduces fuel flow and can cause ignition misfires.
Procedure:
62.Close the shut-off valve on the supply line.
63.Remove the filter bowl using a filter wrench.
64.Remove the old filter element and discard it.
65.Clean the bowl with an appropriate solvent.
66.Install the new filter element and reassemble the bowl.
67.Check the bowl gasket for a proper seal.
68.Open the shut-off valve and check for leaks.
Combustion Adjustment
Flue Gas Analysis
Flue gas analysis is essential for optimizing burner efficiency and minimizing emissions. You must use a calibrated combustion analyzer to measure:
O₂ (oxygen): 3 to 5% for optimal combustion
CO₂ (carbon dioxide): 10 to 13% depending on fuel
CO (carbon monoxide): must be below 100 ppm
NOₓ (nitrogen oxides): per local requirements
Flue gas temperature: should be as low as possible to maximize efficiency
Measurement Procedure:
78.Drill a test hole in the flue pipe, at least 30 cm from the start of the pipe.
79.Insert the analyzer probe into the flue pipe.
80.Start the burner and allow the temperature to stabilize (about 5 minutes).
81.Record the O₂, CO₂, CO, and temperature readings.
82.Adjust the air shutter and pump pressure if necessary.
Combustion Efficiency Calculation:
Combustion efficiency can be estimated using the following formula:
Efficiency (%) = 100 − (Flue Gas Losses)
Flue gas losses are calculated from the flue gas temperature and CO₂ content. A simplified method:
Losses (%) = (Flue Gas Temperature − Ambient Temperature) × Loss Factor
Where the loss factor depends on the fuel and CO₂. For light fuel oil (No. 2), with 12% CO₂, the factor is approximately 0.35% per °C.
Example:
Flue gas temperature: 260 °C
Ambient temperature: 20 °C
CO₂: 12%
Losses = (260 − 20) × 0.35 = 84% → Efficiency = 100 − 84 = 16% (this is a simplified example; in reality, typical efficiency is 80 to 85%).
Air Shutter Adjustment
The air shutter controls the amount of combustion air. Incorrect adjustment results in:
Excess air (O₂ > 5%): efficiency loss, flame cooling.
Insufficient air (O₂ < 3%): incomplete combustion, soot and CO production.
Adjustment Procedure:
99.Measure CO₂ or O₂ with the analyzer.
100.Adjust the air shutter in small increments (1/4 turn).
101.Wait 2 minutes between each adjustment for stabilization.
102.Aim for a CO₂ of 11 to 12% for No. 2 fuel oil.
103.Check CO: it must be below 100 ppm.
104.Check the flame: it should be yellow-orange with a blue tip, stable, and smoke-free.
Pump Pressure Adjustment
Pump pressure determines fuel flow rate and spray quality. Pressure that is too high produces an overly fine spray; pressure that is too low produces droplets that are too large.
Procedure:
108.Install a pressure gauge on the pressure port.
109.Start the burner.
110.Adjust the pump pressure regulating screw.
111.The rated pressure is typically 100 psi (689 kPa) for residential burners.
112.Verify that the pressure remains stable during operation.
Smoke Test
The smoke test (Bacharach scale test) is used to evaluate combustion quality.
Procedure:
116.Use a smoke pump with a filter paper.
117.Take 10 samples through the flue pipe.
118.Compare the resulting stain to the Bacharach scale (0 to 9).
119.A reading of 0 to 1 is acceptable; a higher reading indicates a combustion problem.
Boiler and Combustion Chamber Maintenance
Cleaning the Combustion Chamber and Heat Exchanger
Soot buildup on heat exchange surfaces reduces efficiency and increases flue gas temperature.
Procedure:
124.Remove the burner from the combustion chamber.
125.Open the access doors or inspection plates.
126.Clean the heat exchanger surfaces with a wire brush and a soot vacuum.
127.Inspect the refractory (fire brick) condition and replace if cracked.
128.Inspect the flame deflector condition.
129.Clean the combustion chamber floor and remove ash and debris.
Flue Pipe Inspection
The flue pipe must be inspected for obstructions, leaks, and corrosion.
CSA B139 Requirements:
The flue pipe must be in good condition, without cracks or corrosion.
The flue pipe must be gas-tight against combustion products.
The flue pipe must be installed with an upward slope of at least 2% toward the chimney.
The flue pipe must be supported at intervals of no more than 1.5 m.
Inspection Procedure:
138.Visually inspect the flue pipe along its entire length.
139.Check joints and fittings.
140.Test for leaks by temporarily blocking the end and observing for leaks.
141.Clean the flue pipe if soot buildup exceeds 3 mm.
Storage Tank Maintenance
Aboveground Tank Inspection
Aboveground tanks must be inspected for corrosion, leaks, and mechanical damage.
Inspection Points:
Corrosion on the tank walls and bottom.
Leaks around fittings and valves.
Condition of the support and foundation.
Presence of dents or deformations.
Condition of the level gauge.
Condition of the vent (must be unobstructed).
CSA B139 Requirements:
The tank must be installed on a stable, level surface.
The tank must be at least 1.8 m from any burner or ignition source.
The tank must be equipped with a vent sized according to the fill rate.
The tank must be equipped with a level gauge.
Underground Tank Inspection
Underground tanks present particular corrosion and leak risks. Their inspection is regulated by provincial and federal authorities.
Procedures:
Periodic leak testing (per regulations).
Cathodic protection inspection if the tank is protected.
Check product level and presence of water in the tank.
Inspect the sump and fittings.
Water and Sediment Management
Water and sediment in the tank can cause corrosion and clog filters.
Check Procedure:
167.Use water-finding paste on a gauge stick to detect the presence of water.
168.If water is present, pump it out using a transfer pump.
169.Check for sediment at the bottom of the tank.
170.Recommend fuel treatment if necessary.
Troubleshooting Common Failures
Burner Does Not Start
| Possible Cause | Check | Corrective Action |
|---|
| No electrical supply | Check circuit breaker and switch | Restore power |
| Defective thermostat | Test thermostat | Replace |
| Defective relay or control | Test relay | Replace |
| Defective burner motor | Test motor | Replace |
| Dirty or misadjusted electrodes | Inspect electrodes | Clean or adjust |
| Clogged nozzle | Inspect nozzle | Replace |
| Defective pump | Test pressure | Replace |
Burner Starts but Shuts Down After a Few Seconds
| Possible Cause | Check | Corrective Action |
|---|
| Dirty photocell | Clean the cell | Clean or replace |
| Defective photocell | Test the cell | Replace |
| Misadjusted electrodes | Check gap | Adjust |
| Clogged nozzle | Inspect nozzle | Replace |
| Insufficient oil supply | Check filter and line | Clean or replace |
Incomplete Combustion (Black Smoke)
| Possible Cause | Check | Corrective Action |
|---|
| Excess fuel | Check pump pressure | Adjust pressure |
| Insufficient air | Check air shutter | Open the shutter |
| Worn or incorrectly sized nozzle | Inspect nozzle | Replace |
| Clogged air filter | Inspect filter | Clean or replace |
| Blocked flue pipe | Inspect flue pipe | Clean |
Safety and Emergency Procedures
Fuel Leak Procedures
In the event of a fuel leak, you must:
181.Evacuate occupants from the affected area.
182.Disconnect the electrical supply to the burner.
183.Close the shut-off valve on the supply line.
184.Ventilate the area by opening doors and windows.
185.Do not use electrical switches or open flames.
186.Contain the leak with absorbent materials.
187.Notify the appropriate authorities as per regulations.
System Leak Testing
After any service on the oil supply system, you must verify leak-tightness.
Procedure:
191.Open the shut-off valve.
192.Pressurize the system by starting the burner.
193.Visually inspect all fittings and joints.
194.Use a leak detector or soap solution on the fittings.
195.Verify that the pump pressure remains stable.
Personal Protective Equipment (PPE)
PPE required for maintenance work includes:
Safety glasses
Chemical-resistant gloves
Safety footwear
Protective clothing (coveralls)
Respiratory protection if needed (cartridge mask for organic vapors)
Tools and Measuring Instruments
Essential Measuring Instruments
| Instrument | Use | Required Accuracy |
|---|
| Combustion analyzer | Measures O₂, CO₂, CO, temperature | ±0.1% O₂, ±1 ppm CO |
| Pressure gauge | Pump pressure | ±1 psi |
| Vacuum gauge | Suction vacuum | ±0.1 in Hg |
| Multimeter | Voltage, resistance, continuity | ±0.5% |
| Thermometer | Flue gas temperature | ±1 °C |
| Smoke tester | Bacharach scale | ±0.5 |
Instrument Calibration
Measuring instruments must be calibrated regularly to ensure accurate readings. Recommended calibration frequency:
Combustion analyzer: every 6 months or per manufacturer recommendations
Pressure gauge: annually
Multimeter: annually
Applicable Standards and Codes
Canadian Electrical Code, Part I
The Canadian Electrical Code, Part I (C22.1-21) applies to the electrical installations of oil heating systems. Key rules include:
Rule 8-200: Calculation of electrical load for circuits.
Rule 26-700: Installation of motors and controls.
Rule 26-702: Protection of burner circuits.
Rule 26-704: Burner service switch.
Key Requirements:
The burner must be supplied by a dedicated circuit.
A service switch must be installed near the burner.
The circuit must be protected by a circuit breaker or fuse sized according to the load.
Grounding must comply with code requirements.
CSA B139
CSA B139 (Installation and Maintenance of Oil-Burning Equipment) covers all aspects of the installation and maintenance of oil heating systems.
Key Requirements:
Article 4.3: Requirements for room ventilation.
Article 5.2: Requirements for fuel supply.
Article 6.1: Requirements for storage tanks.
Article 7.2: Requirements for flue pipes.
Article 8.1: Requirements for maintenance and repairs.
CSA B149.1
CSA B149.1 (Natural Gas and Propane Installation Code) applies to gas installations, but certain requirements may apply to combined oil-gas systems.
Documentation and Records
Maintenance Log
A maintenance log must be kept for each installation. This log must include:
Date of maintenance
Technician's name
Description of work performed
Parts replaced
Measurement results (CO₂, CO, temperature, pressure)
Recommendations
Maintenance Label
A maintenance label must be affixed to the burner after each maintenance visit. This label must include:
Date of maintenance
Name of the technician and company
Combustion test results
Type of nozzle installed
Pump pressure
Summary
Annual maintenance is mandatory for residential oil burners; commercial installations require semi-annual maintenance.
Nozzle and oil filter replacement is required at every annual maintenance visit.
Typical electrode gap is 3.2 mm with a distance of 6.4 mm above the nozzle.
Pump pressure must be checked and adjusted to 100 psi (689 kPa) for most residential burners.
Flue gas analysis should target a CO₂ of 11 to 12% and CO below 100 ppm.
Typical combustion efficiency is 80 to 85% for a properly adjusted system.
The Bacharach smoke test should give a reading of 0 to 1.
The Canadian Electrical Code, Part I (Rule 8-200) and CSA B139 are the reference standards.
Any fuel leak must be corrected immediately and emergency procedures followed.
A complete maintenance log must be kept for each installation.
Common Pitfalls to Avoid
261.Do not confuse units: nozzle flow rate is in USGPH, not imperial gallons. One US gallon = 3.785 L; one imperial gallon = 4.546 L.
262.Do not skip the smoke test: a smoke test is mandatory after any combustion adjustment.
263.Do not forget to check the photocell: a dirty cell is a common cause of intermittent failures.
264.Do not overtighten the nozzle: excessive tightening can damage the seat and cause leaks.
265.Do not ignore vacuum pressure: a vacuum pressure above 10 in Hg indicates a restriction in the suction line.
266.Do not confuse the standards: CSA B139 applies to oil, CSA B149.1 applies to natural gas and propane.
267.Do not forget to disconnect the electrical supply before any work on the burner.
268.Do not neglect the leak check after any work on the supply system.
269.Do not use non-certified parts: all replacement parts must be CSA-certified.
270.Do not forget to document: maintenance without a written record is considered non-compliant.
271.Do not confuse flue gas temperature with water temperature: flue gas temperature is measured in the flue pipe, not in the boiler.
272.Do not neglect the flue pipe inspection: a blocked flue pipe can cause CO poisoning.
273.Do not forget to check the tank level gauge: an empty tank can draw air into the system and cause pump damage.
274.Do not confuse air shutter adjustment with pump pressure adjustment: these two adjustments affect combustion but in different ways.
275.Do not ignore ventilation requirements: insufficient ventilation can cause incomplete combustion and CO buildup.
