HVAC ENGINEERING versus HVAC DESIGN

David R. Olson, PE

I was recently asked to consider the difference between “Engineering” and “Design”. The following represents my thoughts about this important distinction.

State of Colorado Definitions of Engineering

The licensing requirements for professional engineers are defined by statute in each State. In Colorado, Statute 12-25-114 defines the minimum requirements for registration as a Professional Engineer. This statute requires that an individual first be registered as an EIT (Engineer-in-training). To obtain EIT status, and individual must have completed a 4-year engineering curriculum and successfully complete an 8-hour Fundamentals of Engineering examination. Following four additional years of progressive engineering experience, an individual may apply for admission to a second 8-hour Principles and Practice of Engineering examination. Within this application, the individual shall prove technical competence prior to admission to the examination. Upon satisfactory completion of both exams, the individual may be licensed as a Professional Engineer.

The State of Colorado defines “Engineer” as follows:

Engineer” is a person who, by reason of intensive preparation in the use of mathematics, chemistry, physics, and engineering sciences, including the principles and methods of engineering analysis and design, is qualified to perform engineering work as defined in this part 1.

The State of Colorado defines “Engineering” as follows:

Engineering” means analysis or design work requiring intensive preparation and experience in the use of mathematics, chemistry, and physics and the engineering sciences.

The State of Colorado defines “Practice of Engineering” as follows:

Practice of Engineering” means the performance for others of any professional service or creative work requiring engineering education, training, and experience and the application of special knowledge of the mathematical and engineering sciences to such professional services or creative work, including consultation, investigation, evaluation, planning, design, and the observation of construction to evaluate compliance with plans and specifications in connection with the utilization of the forces, energies, and materials of nature in the development, production, and functioning of engineering processes, apparatus, machines, equipment, facilities, structures, buildings, works, or utilities, or any combination or aggregations thereof, employed in or devoted to public or private enterprise or uses.

Definitions of “Engineer” and “Designer”

The following section includes various definitions of Engineer and Designer from various identified sources. These definitions are offered for the courts consideration, with the understanding that the State of Colorado has their own legal definitions which were stated above.

Engineer:

  • An engineer is a professional practitioner of engineering, concerned with applying scientific knowledge, mathematics, and ingenuity to develop solutions for technical, societal and commercial problems. Engineers design materials, structures, and systems while considering the limitations imposed by practicality, regulation, safety, and cost.

Design – Engineers develop new technological solutions. During the engineering design process, the responsibilities of the engineer may include defining problems, conducting and narrowing research, analyzing criteria, finding and analyzing solutions, and making decisions. Much of an engineer’s time is spent on researching, locating, applying, and transferring information.[5] Indeed, research suggests engineers spend 56% of their time engaged in various information behaviors, including 14% actively searching for information.

AnalysisEngineers apply techniques of engineering analysis in testing, production, or maintenance. Analytical engineers may supervise production in factories and elsewhere, determine the causes of a process failure, and test output to maintain quality. They also estimate the time and cost required to complete projects. Supervisory engineers are responsible for major components or entire projects. Engineering analysis involves the application of scientific analytic principles and processes to reveal the properties and state of the system, device or mechanism under study. Engineering analysis proceeds by separating the engineering design into the mechanisms of operation or failure, analyzing or estimating each component of the operation or failure mechanism in isolation, and re-combining the components. They may analyze risk. (Wikapedia)

  • A person who has scientific training and who designs and builds complicated products, machines, systems, or structures: a person who specializes in a branch of engineering. (Merriam-Webster Dictionary)

Designer:

  • Mechanical designer is the name given to technicians and other technical people who design parts using CAD but don’t have an engineering degree. This is somewhat similar to industrial designers in that they often do the same thing as some MEs who design on a day to day basis, but do not have the same math, science, and technical theory. They don’t necessarily have less schooling, just different. (IHS Engineering 360)

  • A designer is a person who designs. More formally, a designer is an agent that “specifies the structural properties of a design object“.[1] In practice, anyone who creates tangible or intangible objects, such as consumer products, processes, laws, games and graphics, is referred to as a designer.

The education, experience and genetic blocks that form the base of a competent designer is normally similar no matter the area of specialization, only in a later stages of training and work will designer diverge to a specialized field. The methods of teaching or the program and theories followed vary according to schools and field of study. Today, a design team, no matter the scale of the equipment, is usually composed by a master designer (the head of the team) that will have the responsibility to take decisions about the way the creative process should evolve, and a number of technical designers (the hands of the team) specialized in diverse areas according to the product proposed. For more complex products, the team will also be composed of professionals from other areas like engineers, advertising specialists, and others as required. The relationships established between team members will vary according proposed product, the processes of production, the equipment available, or the theories followed during the idea development, but normally they are not too restrictive, giving an opportunity to everyone in the team to take a part in the creation process or at least to express an idea. (Wikapedia)

Design vs. Engineering:

  • Design consists of the specification of requirements (functional, etc.) needed to satisfy the customer and other relevant external parties (the law, etc.) The job of a designer is to gather such requirements from various sources – asking customers directly, market research, academic research into relevant fields, Domain Knowledge, study of the law and of relevant standards and practices, and a bit of intuition/foresight, and produce a specification of some sort (the exact form is probably not important for this discussion). The designer is concerned with many Human Factors – aesthetics, functionality, ease-of-use, fitness for purpose, and quality; the designer is less concerned with implementation details.

Engineering consists of the translation of these requirements into a technical specification describing a system which conforms to these requirements (which could be then implemented by persons knowledgeable in the craft). Again, the exact form of the technical specification is not important here. In many traditional engineering disciplines, the role of engineer is generally not concerned with things such as aesthetics or fitness-for-purpose; instead the engineer is concerned with coming up with a system (or specification) which is correct, safe, and cost-effective. The chief distinction between an engineer and a designer is that the engineer is personally (legally speaking) responsible for knowing said correctness and safety of the system. The processes of technical specification and other standard procedures exist so that the engineer can convince himself and others of this knowledge. In many fields it is possible for the engineer to be completely unrelated to the design process and only be responsible for the validation of the design. (C2.com/cgi/wiki?DesignVsEngineering)

  • The difference between design and engineering is an engineer can do analysis to figure out if something will work before it’s made. A designer works mostly based on experience, creativity, and what they have seen before.

A mechanical engineer can design as well but typically is using analysis along the way. If you are building a structure or machine that need to work for safety or financial reasons you need to do an analysis to prove they will not fail under use. There are some mechanical engineers that do nothing but this analysis and no design at all. (Reddit.com/Engineering)

  • MEs can basically do whatever interests them from design to analysis to testing to integration, as the last poster said. The ME degree is typically viewed as more advanced, so they can be hired as designers, but a designer wouldn’t be given the title or responsibility (or salary, usually) of an ME. (IHS Engineering 360)

  • Within an engineering company, there are many job positions and divisions, forming a hierarchical structure.  The position in the pyramid of an engineer job is decided on the basis of experience, work duties, decision making power and authority. (Hierarchystructure.com)

  • Some engineering firms may not have any licensed engineers on staff. How do they do this? If they only offer their services to other businesses, and not the public, they don’t need to be licensed. This falls under what is known as an industry exclusion, which says that engineers that work for industry don’t have to be licensed. Such firms typically engage in mechanical design work and act as an extension of a company’s in-house engineering department. Companies often bring in an outside firm when they’re short on staff, get a new project but don’t want to hire staff and then lay them off when the project ends, or if they need engineering experience they don’t have on staff at the time. (Progressive Engineer, How Consulting Engineering Firms Operate)

Discussion

HVAC engineers are capable of technical discernment regarding new and existing building mechanical systems. For example, HVAC engineers may perform system selection, site evaluations, energy studies, cost analysis, technical writing, specification preparation, control sequence writing and evaluation, peer review and code analysis, among other responsibilities.

The HVAC engineer performs the initial analysis, determines the systems that will be utilized in the final design, estimates the cost of the installed system when requested, performs energy studies to determine the justification for upgraded features or system configurations, and creates reports and specifications. On some projects, engineers may provide consulting and/or investigation into existing deficiencies within buildings and make recommendations for corrections. Engineers are often involved in building commissioning and retro-commissioning activities. They utilize their knowledge of systems, experience and training to adjust and configure mechanical systems for superior operation and energy performance.

An HVAC engineer must be knowledgeable with construction techniques and be able to observe construction and determine the contractor’s compliance with the construction documents and the applicable building codes. An engineer must be a good communicator, so that they can clearly state their conclusions and recommendations in written reports and engineering studies.

The HVAC designer performs heat gain – heat loss calculations, selects HVAC equipment with help from equipment sales representatives, designs ductwork and piping systems, and are capable of performing air or water pressure drop calculations using proprietary software or hand calculation methods. They will often size and select various exhaust systems within buildings. HVAC designers rarely utilize any form of advanced mathematics, nor are they required to be trained in chemistry, physics or the engineering sciences. They assist the project engineer to complete HVAC designs in compliance with company standards and the Owners Project Requirements.

An HVAC designer is capable of performing specific tasks for which they are trained. They perform these tasks over and over, becoming proficient at conducting the specific assignment at hand.

Both engineers and designers are critical to a successful building design and construction project. Each has its own particular skills. In my experience, I have found that engineers can perform engineering as well as design. Only in rare cases have I found designers who can perform engineering successfully. Engineers normally have more education, training and experience than designers. This is not always true. I have found designers who are exceptionally capable at what they do, and some designers will graduate into the role of engineer after sufficient training and supplemental education.