Unit 38

One drawback of using custom made, pre-fabricated duct sections is that ____.

• if the measuring was not done correctly, the job may not go together

• altering a duct section at the job site results in lost time

• altering a duct section at the job site is extremely cost-ineffective

• All of the above.

What two fasteners are used with sheet metal square and rectangular duct?

• "S" fasteners (slips) and drive clips.

• Staples and tape.

• Self-tapping screws and draw bands.

• Tabs and adhesives.

What fastener is commonly used with round flexible duct?

• "S" fasteners (slips) and drive clips.

• Staples and tape.

• Self-tapping screws.

• Tabs and adhesives.

A good way to fasten acoustical lining to the inside of sheet metal duct is to use ____.

• "S" fasteners (slips) and drive clips

• staples and tape

• self-tapping screws and draw bands

• tabs and adhesives

What two fasteners are used with fiberglass ductboard?

• S" fasteners (slips) and drive clips.

• Staples and tape.

• Self-tapping screws and draw bands.

• Tabs and adhesives.

____ used at the end of a metal duct run will help reduce any noise that may be traveling through the duct.

• Flexible duct
• metal duct

• super duct

• duct tape

A boot in a duct system is a fitting used ____.

• at the plenum

• between the trunk duct and the branch duct

• between the branch duct and the supply register

• to eliminate vibration between the unit and the duct

A trap in the condensate line prevents ____.

• air from being drawn up into unit from the end of the drain

• foreign particles from being pulled into the condenser

• the pump turning on if the float fails

• Both a and b.

An auxiliary drain pan under the unit is recommended when the evaporator is installed ____.

• above the conditioned space

• near a dry well

• at the end of the house

• next to a driveway or patio

After refrigerant lines have been installed, they should be evacuated to a(n) ____ vacuum.

• average

• low

• moderate

• deep