Oil Heat System Technician Study Guide — Year 1

Year 1 Exam Topics

Study each topic below — these are the core knowledge areas tested in Year 1. Build a solid foundation here before advancing to Year 2 material.

📖Fuel Oil Properties

No. 2 fuel oil (heating oil): most common residential; API gravity 30–39; flash point min 38°C
Viscosity: resistance to flow — affects pump pressure and atomization quality
Sulphur content: low-sulphur (<15 ppm) required in many Canadian provinces
Heating value: approximately 38.7 MJ/L (138,700 BTU/Imperial gallon)

📖Oil Burner Components

Fuel pump: gear pump, pressurizes oil to 100–175 psi; single-pipe vs two-pipe systems
Nozzle: atomizes oil into fine spray; rated in GPH; spray pattern: hollow, solid, semi-solid
Electrodes: create high-voltage spark to ignite oil mist; gap 3/16" (5mm) from nozzle tip
Ignition transformer: 10,000V secondary; spark fires continuously during startup then off

📖Oil Burner Controls

Primary control (stack relay or cad cell relay): proves flame; locks out on no-flame condition
Cad cell: light-sensitive resistor — low resistance in flame (light), high resistance in dark (no flame)
Aquastat: boiler water temperature control; high-limit, low-limit, circulator settings
Thermostat: calls for heat; typically 24V; heat anticipator matched to primary control current draw

💡Combustion Fundamentals

Stoichiometric combustion: perfect air-to-fuel ratio; excess air required in practice (15–50%)
Combustion triangle: fuel + air + heat; remove any one — fire stops
CO₂: measure of combustion efficiency; target 12–13% CO₂ for No. 2 oil
Stack temperature: net stack temp = measured − room temp; target 175–260°C for residential

📖Oil Storage Tanks

Indoor tanks: max 2,500 L for residential without special approval; steel or fibreglass
Outdoor underground tanks (UST): environmental regulations govern installation and removal
Tank accessories: fill pipe, vent pipe (3/4"), gauge, oil supply line, shut-off valve
Two-pipe system: supply and return; used when tank below burner or long line runs

📋Safety & Codes

TSSA (Technical Standards & Safety Authority): Ontario oil burner licensing
CSA B139: Installation Code for Oil Burning Equipment — governs all oil heat work in Canada
CO alarm: required near sleeping areas; test after every service call
Spill response: absorbent material; report to environment ministry if spill exceeds threshold

Study each topic below — these are the core knowledge areas tested in Year 1. Build a solid foundation here before advancing to Year 2 material.

📖Combustion Analysis

Electronic combustion analyser: measures O₂, CO₂, CO, stack temp, draft simultaneously
O₂ target: 4–6% (corresponds to 15–30% excess air for No. 2 oil)
CO: must be <400 ppm air-free; elevated CO = incomplete combustion — check air settings
Smoke test: Bacharach scale 0 (clear) to 9 (heavy black); target trace to 1 on residential

📖Boiler Systems

Hot water boiler (hydronic): low mass or high mass; circulator pump; expansion tank; pressure relief valve
Steam boiler: low pressure (15 psi max); Hartford Loop prevents dry firing; water gauge glass
ASME Section I (power boilers) and Section IV (heating boilers): design and construction codes
Annual service: flush boiler, check water level, test relief valve, inspect flue passages

📖Forced Air Oil Furnace

Components: burner, heat exchanger, blower, air filter, controls; efficiency 80–87% AFUE
Heat exchanger inspection: CO test and visual; cracks allow combustion gases into air stream
Static pressure: measure supply and return plenum; high static = restricted airflow
Temperature rise: measured supply temp − return temp; target matches furnace nameplate (typically 50–80°F)

📖Hydronic System Design

Series loop: all baseboard in one circuit; simple but last zone coldest; use only for same size/length
Monoflow system: tees divert small flow to each baseboard while main loop continues
Zoned systems: multiple circulators or zone valves; each zone independently controlled
System balancing: balance valves and flow meters ensure correct flow to each zone

📖Efficiency & Upgrades

AFUE (Annual Fuel Utilization Efficiency): measures seasonal efficiency; standard 80–87%; no condensing oil units common
Flame retention burner: recirculates flue gases for better mixing; more efficient than conventional
Boiler reset controls: reduce boiler temperature based on outdoor temperature — saves 10–15%
Tankless coil vs indirect water heater: indirect far more efficient for domestic hot water

📖Venting & Draft

Natural draft: relies on buoyancy of hot flue gases; chimney height creates draft
Draft measurement: over-fire (in combustion chamber) and breeching; target −0.02 to −0.04 in. WC
Barometric damper: automatic draft control — opens to bleed in room air and stabilize draft
Category I appliances vent naturally; must not be combined with other fuel types in same chimney