The best investment a client can make is to pay for a design where it obtains maximum efficiency, minimum ecological impact and maintains its parameters throughout its useful life.
By Eng. Camilo Botero*
Every good HVAC project, which includes air conditioning for human comfort, ventilation and industrial applications, begins with a design of excellence and therefore in this column I will give guidelines that lead to designs being the starting point of successful projects.
It obviously begins by defining the precise scope of the project and clearly writing these objectives so that there is no misunderstanding and then establishing the basis of the design.
In my opinion, the design of the air conditioning should be carried out by professionals in Mechanical Engineering and / or Thermal Engineering, with professional registration, and where it exists, with certification, to develop designs in air conditioning. Why do I make this proposal that seems discriminatory, but it is not?, basically because in these careers the subjects that are fundamental in the elaboration of the projects are taught with all rigor: physics, mathematics for engineers, thermodynamics, power and refrigeration cycles, heat transfer, mechanical fluid heat exchangers, turbomachinery (pumps, fans, compressors, turbines, blowers), thermal plants and of course air conditioning and refrigeration.
It is obvious that any professional can acquire this knowledge if he proposes it, but I can almost assure, without mistake, that he does not manage to deepen and integrate all the fundamentals, as is done in Mechanical Engineering and especially in Thermal Engineering, which is taught as a master's degree in Mechanical Engineering.
However, in reality "everyone and Don Raimundo", makes air conditioning projects (but not the complex projects of Thermal Engineering in the industry), because it is very easy to follow the manuals that in good time have developed the manufacturers of the equipment and components used in air conditioning, and especially the thermal load calculation software, that give the feeling to those who use them that they are making a "good" design, but the reality is different, because very often errors are made in the data that feed the software, usually due to ignorance of the fundamental theories.
The designer of projects in air conditioning must know in depth in addition to the above, the principles of theoretical and applied psychrometry, as well as thermofluids, with their associated differential equations, which allow him to develop mathematical models of some complexity.
As for the calculation of the thermal load, this is more an art than technology, based on these principles, it takes a lot of experience, knowledge of the climatology, architecture and construction materials of the area where the project is carried out and the load profile of the building.
Here I will add something that sounds like heresy and that brings me problems when I dictate the class of calculation of thermal load, and that is that the software for this function, which are excellent for comfort projects with a large number of rooms, lounges, auditoriums, dining rooms etc., if you do not have the knowledge and experience, give rise to huge errors, to be misused, and this I can see frequently in my work of auditing and commissioning in the execution of projects.
To emphasize that what I say is true, when I give the class on the subject of thermal load estimation I always do the following exercise: I ask my students to calculate the thermal load of the room where we are, consulting all the texts, using the software of their choice, interacting with their peers, and if there are 20 students and the most likely answer is 5 TR, when making the normal distribution of the answers, which are all different, there are two or three close to this value and the others range from 1 TR to 20 TR or more.
Technical skills are only half the story, and it becomes clear that the designer must learn certain business skills if he wants to achieve professional independence (a paramount principle in my office); and how to define the identity of their specific designs on each occasion (abolish the "copy and paste", as usual) and appropriate the expertise to make their own professional performance and be responsible for their future, learning survival techniques.
In designer of air conditioning projects he tries to find solutions to specific problems and technical needs, whose results are always measurable and must find his own form and style, his niche market and in my view, have an ethical and transparent performance where commissions are not received from manufacturers or contractors who will participate in the execution of their designs. His commitment is fundamentally with his client and with the project in execution, which will always keep him working, since he will earn the trust of his clients.
Designers are not magicians who solve all problems, because we work with the laws of physics mainly the first and second laws of thermodynamics, which are inviolable. As I sometimes tell my clients jokingly and seriously: "I studied engineering, not palmistry!", when they ask me for solutions that go against those laws of thermal sciences, as in the solutions with bioclimatic architecture to achieve conditions of human thermal comfort, in tropical climates that is the case of the city where I live and where I frequently find failed bioclimatic solutions.
The HVAC Project Office
The marketing of an HVAC project office is very typical of the sale of technical services, to which I will make some comments based on my current experiences and the market conditions of such activity in our environment. These truths are as follows:
The first is that there is a latent need for such designs (especially in Thermal Engineering for industry), which depends essentially on the specific technical skills of an engineer who has them, has proven to be effective with them and who can certify them with solutions already tested and repeatable in a particular case. That is, there is a market little exploited, but that does not appreciate the importance of design.
The second is that getting the job is harder than doing it, there are too many reasons for it and one is that there is no obligation to hire designs and another is that there are many contractors or team representatives who offer "free design", if they get the project or if they buy their equipment ... Here I also make the classic joke to my clients..."That's as a doctor with funeral home, drugstore and spa; They win with the dead, with the sick and with the healthy."
Since there is no such thing as objective and appropriate design for a specific project, which is "free", the best investment a client can make is to pay for a design where it obtains maximum efficiency, minimum ecological impact and maintains its parameters throughout its useful life.
The Spanish RITE specifies this very clearly. In addition, the value of the design in our environment only represents the order of 3% of the total value of the project and sometimes even less. In Colombia we have not managed to approve a RITE that I promoted 11 years ago and that was presented in four ministries fully suitable for implementation. We still have no regulations for HVAC projects and that is a source of failed projects, corruption and bad engineering practices.
The third truth is that every technical skill has its life cycle, therefore, the designer must remain in the state of the art of our trade, attending fairs, congresses, seminars, courses, being a teacher in the guild and the formal academy, developing standards, participating in guild activities, achieving professional titles or technical certifications, giving conferences, writing technical articles and books. In these challenging times where technology is changing rapidly, the designer is forced to study every day.
In general, if the design office does not have high fixed costs, having a few clients who appreciate their knowledge and who pay what their engineering services are really worth, is enough. It is not a business of many but of good customers.
I use the internet to communicate permanently with my clients, guilds and peers in engineering, as well as to consult specific details of a project since, in the network, there is an amount of knowledge of incredible dimensions. When I did my first Air Conditioning design course in 1981, in the factory of one of the most recognized companies in the sector, the printed material they gave us, weighed 33 Kg...! That information today can be carried in a card-like electronic memory and in the wallet.
The use of digital files helps projects to be stored on the PC, on electronic memories, CDs, or on removable disks to support them. The same happens with the catalogs of which I have two rooms with libraries full of these, but with the help of the internet, they are becoming obsolete, I have been giving my students and alumni a good amount of this printed material, but as they also access the internet or digital information provided by manufacturers, I receive them less and less; I'm already decommissioning them as recyclable material.
Finally, I note that technical sales visits and how to develop skills for them, projecting a reliable image, are fundamental since what the designer has to sell are their knowledge and confidence through billable hours; That is why you must be so demanding with the time you spend on those visits and meetings associated with projects that sometimes become endless and are not billable.
You must also earn the appreciation and respect of the customer, without becoming your "employee"; Highlight the specific need of a client, because from there usually more business is born. You must address all of your client's objections and interests by being selective with such clients.
* Camilo Botero was Secretary of the Federation of Ibero-American Associations of Air Conditioning and Refrigeration - FAIAR; He was president of ACAIRE and is president of Camilo Botero Ingenieros Consultores Ltda. He is currently a professor at his CBG Academy. He has also worked as a teacher in several Colombian universities, guilds and currently in ACAIRE in diploma courses of air conditioning projects, energy efficiency in air conditioning and refrigeration, cogeneration and trigeneration, applied psychometrics, thermodynamics, fluid mechanics, heat transfer and turbomachinery.
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