Phase 4: Unit 303 Combustion 3

What is the primary function of a forced draught burner?

• To increase air pressure

• To decrease air pressure

• To maintain air pressure

• To eliminate air pressure

Forced draught burners are commonly used in which of the following applications?

• Residential heating

• Industrial boilers

• Air conditioning

• Refrigeration

The efficiency of radiant type appliances is primarily due to their use of ______.

• Convection

• Radiation

• Conduction

• Evaporation

What is a common use for radiant type appliances?

• Cooking

• Cooling

• Freezing

• Drying

In a pre-mixed appliance, gas and air are mixed using a ______.

• fan

• gas/air ratio valve

• atmospheric pressure

• electric pump

Pre-mixed burners can still be classed as ______ draught, as the air for combustion is pushed in.

• Natural

• Induced

• Forced

• Passive

In a forced draught burner, what is usually responsible for flame retention?

• A) Eddies of hot gases

• B) Cold air currents

• C) Water vapor

• D) Electric spark

How is the amount of air adjusted in a forced draught burner?

• By a damper

• By a valve

• By a switch

• By a lever

What is used on living flame effect?

• Pre-aerated flame

• Post-aerated flame

• Non-aerated flame

• Fully-aerated flame

Radiant plaque heaters stabilize a pre-aerated gas/air mixture upon what type of surface?

• Metal surface

• Ceramic surface

• Plastic surface

• Glass surface