Flue Systems

What is a flue system?

• AA heating unit
• BA passage for removing combustion products from an appliance to outside✓
• CA duct for fresh air
• DPart of the boiler only

Answer: Flue systems safely extract combustion products to the outdoor environment.

What are the main types of flues?

• AJust chimneys
• BOpen flues, room-sealed, balanced flues, and fan-assisted✓
• COnly plastic
• DVaries by manufacturer

Answer: Flue types include open chimney, room-sealed, balanced flue, and fan-assisted designs.

What is a natural draft flue?

• AA forced-air flue
• BA flue relying on the natural pressure difference (buoyancy) to exhaust gases✓
• CAn indoor duct
• DElectronic control

Answer: Natural draft flues rely on hot gas buoyancy to drive gases out without a fan.

What is the minimum height requirement for a chimney in relation to the roof?

• ALevel with roof
• BAt least 600mm above the highest point of the roof✓
• C300mm minimum
• DNo height requirement

Answer: Chimneys must extend at least 600mm above the roof's highest point to ensure proper draft.

What is a balanced flue terminal?

• AA regular vent
• BA fitting that safely exhaust gases while drawing in combustion air through concentric ducts✓
• COnly an exhaust
• DJust any outlet

Answer: Balanced flue terminals use concentric ducts for safe outside air intake and gas exhaust.

Where can a balanced flue terminal be positioned?

• AOnly on the roof
• BOn walls, roofs, or chimneys with proper clearance from windows and openings✓
• CAnywhere
• DOnly horizontally

Answer: Balanced flue terminals can be vertical (roof) or horizontal (wall) with required safety clearances.

What is a fan-assisted flue?

• AAn open flue with a fan
• BA flue using a motor-driven fan to ensure gases are expelled reliably✓
• CJust a ventilation fan
• DNot common

Answer: Fan-assisted flues use electric fans to ensure consistent, reliable gas exhaustion.

What happens if a chimney is too short?

• ANo problem
• BInsufficient draft, causing incomplete combustion and potential CO spillage✓
• CFaster heating
• DJust cosmetic issue

Answer: Short chimneys have insufficient draft, risking dangerous combustion gas spillage.

What is flue blockage risk from?

• ANothing
• BDebris, bird nests, soot, or structural damage✓
• CAge alone
• DNot a concern

Answer: Flues can be blocked by debris, nests, soot, or internal damage, causing dangerous spillage.

What is a flexible flue liner?

• AA rigid pipe
• BA flexible metal or plastic tube inserted into an existing chimney to improve draft and safety✓
• CA temporary duct
• DNot used

Answer: Flue liners improve draft in old chimneys and provide a gas-safe sealed passage.

What is the purpose of a flue terminal?

• AJust looks good
• BTo safely disperse gases outside while preventing rain or debris entry✓
• CTo increase draft
• DOptional feature

Answer: Flue terminals safely exit gases, protect against weather, and prevent downwind drafting.

What is downdraft in a flue system?

• AWind speed only
• BWind pressure reversing normal draft, causing gases to flow back into the home✓
• CCold air
• DNot a concern

Answer: Downdraft occurs when wind pressure reverses flue draft, risking dangerous gas spillage.