This article deals with your personal safety when installing a new or replacement furnace. Topics covered include emergency procedures; clothing and safety gear; fall protection; electricity; lock out, tag out; GFCI; fuel safety; and confined spaces.

These conditions were noted in an energy audit report: “The fire/smoke damper was closed.” “The coils are still dirty.” These are not unusual examples. Since 40 percent of the energy used in the United States is used to operate buildings, it is obvious that a big step in making America green is to make our buildings green.

Every manufacturer of an HVAC digital control system uses the DDC to perform pretty much the same functions. The catch is that each DDC system has different ways of letting you use these functions. If you are used to operating computers, you have the basic knowledge required.

Remember that automatic control systems are automatic in operation, but not self-repairing. Unless a building has a service contract with a reputable controls contractor to inspect and calibrate the HVAC control system every six months, it is very likely that the HVAC system is not providing maximum comfort.

If you are like most in the HVAC industry, you are a hands-on person - you don‘t want to mess with a lot of theory, but just get in and get the job done. But a refrigeration system is different from most of our work.

If you work in the HVAC industry, you are concerned with the process of conditioning air and moving air from one area to another. It makes sense that you need to know how air flows in ducts and what factors affect the flow.

A technician often has to sketch or design ductwork and other parts of an HVAC system. This means working with lines, angles, and other shapes. This article shows you how to draw and work with these different figures.