What are the two operating principles for any chimney or flue system according to the Level 3 Diploma in Plumbing and Domestic Heating?

• Remove combustion products to the inside and draw in air for combustion.

• Remove combustion products to the outside and draw in water for combustion.

• Remove combustion products to the outside and draw in air for combustion.

• Remove water vapor to the outside and draw in air for heating.

On what principle do chimney or flue systems operate to create 'up draught'?

• The principle that cold gases sink, creating a pressure difference.

• The principle that hot gases rise, creating a pressure difference called 'up draught' via conduction.

• The principle that hot gases rise, creating a pressure difference called 'up draught' via convection.

• The principle that hot gases rise, creating a pressure difference called 'down draught' via radiation.

What is the basic concept of a chimney or flue system?

• To cool down the air inside a room

• To create an up draught to get rid of the fumes

• To filter pollutants from the air

• To circulate warm air within a building

What is the other flue design mentioned in the material apart from natural draught?

• Chimney sealed

• Room sealed

• Open vent

• Mechanical vent

What is the simplest design of all flues that relies on heat rising to create the up draught?

• Forced draught flue

• Chimney flue

• Open flue

• Balanced flue

Open flues can be of which two types?

• Natural draught or forced draught

• Natural draught or balanced draught

• Forced draught or direct draught

• Balanced draught or direct draught

Where is the air for combustion taken from in an appliance with an open flue?

• From outside the room only

• From the room in which the appliance is located

• From the combustion chamber

• From the secondary flue

How are the products of combustion removed in an appliance with an open flue?

• Through a vent in the room

• Up the flue by natural draught

• Directly outside through a side vent

• Through the combustion chamber

What must be supplied to the room and appliance from outside via a vent in an open flue system?

• Natural gas

• Combustion air

• Exhaust gases

• Cooling air

What is the purpose of the fan in an open flue with forced draught?

• To cool down the appliance

• To create a positive up draught by blowing the products of combustion up the flue

• To filter the products of combustion

• To increase the efficiency of fuel consumption