G3 HVAC PrepBOX

Ontario G3 Gas Technician exam preparation

Free G3 Gas Technician Practice Questions

18 sample questions from the Ontario G3 exam question bank, with the answers shown. These are a fair cross-section of all 9 topics — not the easy ones. The full bank holds 1,184 questions.

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Appliances & Heat Transfer

Appliances & Heat Transfer

What is the maximum BTU input rating for appliances that a G.2 certificate holder may install, inspect, alter, purge, activate, repair, service or remove?

Appliances & Heat Transfer

Which testing agency is NOT recognized for certifying propane appliances in the Province of Ontario?

Controls & Ignition

Controls & Ignition

What is a thermopile (powerpile) used for in gas appliances?

Controls & Ignition

'Yellow tipping' in a burner is an indication of:

Electricity & Controls

Electricity & Controls

What setting must a gas technician use when measuring an unknown source of power with an analogue meter?

Electricity & Controls

What is a capacitors job?

Gas Code & Piping

Gas Code & Piping

After appliance installation, what is the minimum time the gas pressure must be maintained during the low-pressure leak test?

Gas Code & Piping

When purging a gas piping system, which appliance should be purged first?

Gas Properties & Combustion

Gas Properties & Combustion

What is the chemical formula for methane, the primary component of natural gas?

Gas Properties & Combustion

What is the boiling point of propane at atmospheric pressure?

Regulations & TSSA

Regulations & TSSA

Meter and service regulator installations shall be made in accordance with:

Regulations & TSSA

A certificate holder must inform the Technical Standards and Safety Authority of a change of address within __________ days.

Safety & Workplace

Safety & Workplace

What type of piping are tube benders designed to be used for?

Safety & Workplace

What types of copper tubing are permitted by Code?

Tools & Measurements

Tools & Measurements

What are the three types of flue gas analyzers?

Tools & Measurements

What is the maximum pressure drop allowed for a propane piping system operating at 11 inches water column?

Venting & Combustion

Venting & Combustion

What is a vent connector?

Venting & Combustion

In a forced-draft burner system, where is the combustion air supplied from?

Practising properly

Reading answers is not studying. Work a question before looking, get it wrong, then find out why — that is what makes it stick. The app keeps every question you answer incorrectly in a Challenge Bank so you can drill your weak spots rather than the material you already know.

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