Unit 38 Review Question

A float switch, located in an auxiliary drain pan, is typically wired to

• open the line voltage circuit to the air handler

• cycle both the evaporator and condenser fans.

• open the low-voltage control circuit.

• control a condensate pump.

Two common methods for preventing the vibration of a package system from being transferred to the building or structure are

• canvas connectors and duct insulation

• using fiberglass ductboard and flex duct

• rubber and cork pads and spring isolators

• a roof curb and rigging holes

Flexible duct used at the end of a metal duct run will

• cause excessive friction losses

• cause the duct to collapse and reduce its inner diameter

• help reduce noise transmission in the ducts

• greatly reduce airflow and should be avoided

Square duct or rectangular duct is assembled with

• "S" fasteners and drive clips

• mastic and drive clips

• foil tape and mastic

• "S" fasteners and zip ties

On a line set used to install a split-system, the ______ line is insulated.

• liquid

• compressor discharge

• suction

• smaller

When installing the condensing unit of a split-system, it should be

• set on a concrete or high-impact plastic pad

• located out of sight, such as under a deck

• lifted off the ground 24 in. to 48 in

• located near a municipal water source for cleaning

The applied voltage (the voltage that the unit will actually be using) should be within ±_____% of the rated voltage of the unit.

• 3

• 5

• 10

• 15

Before a newly installed system is started up, it is recommended that

• the service valves are returned to their closed position

• the crankcase heater be allowed to operate for a specified period of time

• the condenser be cleaned with a foaming cleanser

• the factory Schrader pins be replaced with new ones

When joining two sections of fiberglass ductboard

• glue or spot welds are used

• staples and tape are used

• "S" fasteners and drive clips are used

• a minimum of three screws should be used

The __________ provides installation standards, wire sizes, methods of routing wires, and types of enclosures for wiring and disconnects.

• National Fire Protection Association (NFPA)

• International Fuel Gas Code (IFGC)

• National Electrical Code (NEC)

• U.S. Department of Energy (DOE)