Sheet Metal, Level 3, 4th edition

Module ID 03201 - Commercial Airside Systems

You may have seen office buildings and shopping

malls with many air conditioning units on

the roof. These are likely to be packaged units

in which the ductwork penetrates the building.

Large buildings have different needs than small

buildings. For example, some zones in the building

may be calling for heat, while others are calling

for cooling, and others are making no demands.

The system design must accommodate these differences.

In commercial systems, it is common to

find single systems serving multiple zones, with

each zone having its own comfort control device.

These applications require special air distribution

equipment not commonly found in residential

applications. (12.5 hours)

Module ID 04303 - Principles of Airflow

Before an air distribution system is manufactured,

mechanical engineers make calculations,

work through options, and often negotiate with

other engineers in other specialties to produce the

plans. Value engineering–comparing projected

costs to the return on investment–is also a significant

factor. Understanding principles of airflow

will help craftworkers better appreciate the design

process and recognize why systems are designed

as they are. This module explains how airflow is affected

by duct size, shape, and material of construction.

Features such as turning vanes that increase the

efficiency of airflow in an elbow, minimize turbulence,

and ensure the best possible airflow are

explored. Trainees are provided with the necessary

knowledge to fabricate and install systems

from a performance perspective and learn why

this is important to building owners and their

occupants. (25 hours)

Module ID 04308 - Using Construction Drawings in Sheet Metal

Construction drawings and documents govern

the way a project is accomplished. Using these

documents will not only guide the construction

process and outline the required results, but it

is also useful in the preparation of equipment

schedules, material takeoffs, and craft scheduling.

This module explains how to put knowledge of

construction drawings and documents to work as

a sheet metal fabricator or installer, emphasizing

the ways in which they usually interact with the

drawings. (30 hours)

Module ID 04305 - Sheet Metal Job Specifications

Plans, specifications, and submittals are documents

that describe in exact detail how a building

is to be constructed and the required characteristics

of the materials used. The specifications document

outlines instructions and standards for how

the work is to be performed, while submittals

specify the equipment to be installed, and both

must be followed closely. It is critical that the various

trades on site coordinate their work with one

another prior to the beginning of construction. It

is also important to coordinate the order in which

things are installed so that one trade’s work does

not hinder access for another trade that will be

working later in the same space. This module will

cover how the specifications and submittal documents

are applied when accomplishing work for a

specific job. (20 hours)

Module ID 04402 - Air Testing and Balancing

Even when a forced-air comfort system is properly

installed and operating, the air must be properly

distributed to the spaces. Therefore, after the

system is installed and running, the air must be

properly balanced. This process requires a deep

understanding of airflow fundamentals and the

ability to use specialized test instruments to measure

air pressures, velocity, and volume. (30 hours)

Module ID 19202 - Blanket Insulation for Ducts

Fiberglass is what most people think of when they

think about insulation, specifically the pink, fluffy

fiberglass usually found in home attics. While the

fibrous pink insulation is not generally used in

the mechanical insulation trade, there are several

types of fiberglass insulation that are. This module

will introduce you to the blanket form of glass

fiber insulation. (7.5 hours)

Module ID 19203 - Board Insulation For Ducts

There are two types of insulation primarily used

on duct systems: fiberglass blanket and fiberglass

board. They are somewhat similar in construction.

Fiberglass blanket is generally easier to work with

but is less durable. Fiberglass board, the subject of

this module, requires more effort to fit to the duct

but is longer lasting. (20 hours)