fuels ppt 3-2-2

What is the recommended minimum angle for bends in chimney/flue systems to reduce frictional resistance?

• 30 degrees

• 45 degrees

• 60 degrees

• 90 degrees

Why is the effective height of a chimney/flue system different from the physical measured height?

• It accounts for temperature changes

• It includes the length of the chimney

• It considers the frictional resistance encountered

• It measures the width of the chimney

What is necessary for a flue to work efficiently?

• The temperature needs to rise quickly and remain constant.

• The temperature should decrease gradually.

• The flue gases should move slowly.

• The flue should remain cool.

What can happen when the flue is cool?

• The flue gases move efficiently upwards.

• The flue gases move slowly and can create condensation.

• The flue heats up immediately.

• The flue gases do not spill.

How long can it take for the chimney/flue to heat up fully?

• 1-2 minutes

• 3-4 minutes

• 5-10 minutes

• 15-20 minutes

What is the required velocity for safe evacuation of flue gases?

• 4 m/s

• 5 m/s

• 6 m/s

• 7 m/s

How should the opening of a terminal compare to the cross-sectional area of the flue?

• Equal to the cross-sectional area

• Twice the cross-sectional area

• Half the cross-sectional area

• Three times the cross-sectional area

Where should a terminal be located?

• Inside a pressure zone

• Where it will be a nuisance

• Outside a pressure zone

• Near a window

What is the minimum flue height termination for a pitched roof with a net input of less than 70 kW?

• At ridge, or 600 mm above or at least 1.5 m measured horizontally to the roof line

• 600 mm above the roof line

• 250 mm above the roof line

• 1000 mm above the roof line

For a flat roof with a parapet or external flue and a net input of less than 70 kW, what is the minimum flue height termination?

• At ridge, or 600 mm above or at least 1.5 m measured horizontally to the roof line

• 600 mm above the roof line

• 250 mm above the roof line

• 1000 mm above the roof line