The Commissioning process allows to analyze and verify that all the operational processes of a building work correctly. This method is recommended for those who want to value their properties.
by Camilo Botero*
The stages of pre-design, design, construction, occupation and operation must follow the outlines of the Commissioning (quality assurance) of air conditioning projects.
Commissioning, as is known, is a structured quality assurance process that aims to ensure that the building, when delivered, meets the requirements of the project and for this it is required that the operation and maintenance of the installation is done in a qualified and programmed manner by qualified personnel for it. Every aspect of the project in its pre-design and design phase may contain hidden risks that can adversely affect the quality of subsequent processes.
- In pre-design: the owner's objectives are poorly defined, ambiguous and/or unrealistic.
- In design: the team of designers does not provide the basic data of relevance to start the multidisciplinary design process.
- In construction: the efforts of contractors do not conform to construction documents.
During occupancy and operation: the owner's facilities do not fit their needs or their energy consumption and occurrence of failures are too many, and therefore their operation and maintenance are very expensive.
Each phase-to-phase transition during project execution may contain hidden risks, which affect the quality of the next phase. The owner's goals are not clearly delivered to the design team. This is a very common flaw in our projects. The design team's solution is not clearly delivered to contractors. This is also very common in our projects. Operation and maintenance manuals are not delivered to the owner.
It seems too obvious and / or simple that correctly fulfilling the pre-design sequence, design, construction and operation and maintenance (O & M) in an appropriate way, a good performance of the air conditioning system can be guaranteed throughout its useful life, but there are statistics that confirm that three months after having started a system of which we are concerned, has lost 30% or more of its design conditions, if it has not been properly operated and maintained, with its negative consequences on compliance with design parameters (e.g. lack of comfort), on higher energy consumption, which in turn brings a greater impact on the environment.
It is proven that we are all experts in our professions, we are well trained to design, build, operate and maintain our buildings efficiently and effectively, so why is there inefficiency, failures, non-compliance with specifications or excess pollution? What are we doing wrong?
What happens is that, as ASHRAE Commissioning Specialist Bohanon says today, "there is a high fragmentation between the design, construction and operation of the parts of the 'team' that leads to duplication, conflict and inappropriate use of resources."
We must therefore break this fragmentation between the different phases that make up the execution of an air conditioning project. Commissioning has the solution to this problem, as it favors a process that facilitates and ensures the following aspects through the different phases and disciplines involved:
- Communication
- Documentation
- Verification
This fills in the coordination gaps between civil, mechanical, electrical, hydraulic, data, fire protection engineers; architects and different general contractors.
The Commissioning team includes an important group of members, who change from phase to phase The team is led by Commissioning management, responsibility for tasks must be clearly and contractually assigned, specific roles and responsibilities vary from phase to phase, and must include the following:
- Clear and precise specifications and correct archiving of documents, especially the System Manual, fundamental for the O&M of the air conditioning system.
- Explicit responsibilities of those in charge of the operation and maintenance of the systems or systems, which must be carried out by suitably qualified personnel, hopefully with certification for it, a task in which we are in arrears in our country.
- Meetings, reports and records by the Commissioning team, especially in the O&M phase, because many times well-designed and built systems fail in this phase because the personnel that are assigned to operate and maintain is not the ideal one, putting at risk the permanence and quality of the parameters with which it is designed.
- It must continue with the log that was used for the work, which will be a great support for the O & M, there will be recorded all important events related to the system such as failures, modifications, deterioration, improvements, etc.
Effective Commissioning
When an effective Commissioning is made that includes the O&M phase, the following benefits are obtained:
- A project that usually reflects the needs and desires of the owner.
- A project that works perfectly well, with the initial and final occupation assumed.
- A project that is well documented.
- Personnel who are well prepared to operate and maintain the systems.
- A project with clear performance goals and objectives.
- A project that has benefited from the efforts of the different participants. Satisfied owners and occupants.
- Systems that perform as designed.
- Better documentation of the building and systems.
- Reduced energy use and lower operation and maintenance costs.
- Reduction of service calls a posteriori, to contractors.
- Improved maintenance of equipment and services.
Contractors can benefit from issues that relate construction and quality control processes to design documents. Commissioning authority can benefit from feedback from all aspects of the process. It can identify any system or assembly that does not meet the owner's requirements and quantify the magnitude of such deviations. It also evaluates their operating conditions. Without accusing, it highlights the problems suppressed, highlighting the improved performance, the coordination achieved, the transfer of technology carried out, the documentation delivered etc.
At the start of the O&M phase, Commissioning management:
- Closes the Commissioning process of the construction phase.
- Prepare the owner for a long-term use of the facilities where the project was carried out.
- Completes the tests specified for the occupation and operations phase.
- Minimizes after-sales calls to contractors and suppliers.
- Document lessons learned.
- Provides assistance during matters concerning guarantees.
- Provides assistance with accompaniments to the operations of the installation so that they meet the requirements of the owner.
- Formally closes the process by means of a certificate of delivery of the project to the owner.
- Ensures that the manual of the systems is complete, careful and accessible.
- Makes a workshop of lessons learned that will serve in the future for the O&M of the air conditioning system. The ongoing Commissioning process extends the termination of the original commissioning services.
- It is intended to continue assisting the owner in maximizing the benefits in the use of the facilities for a long time.
Reflections
1.The maintenance of the air conditioning system both in its corrective and preventive modes, as well as the predictive and the one that is carried out "On Conditions" (under conditions) must be of excellence. On its good performance depends the future of the system, failures must be brought as far as possible to "zero", which requires suitability, permanent training and a large dose of sacrifice.
2.The control system, which guarantees that everything works as planned and designed, must remain operational and be maintained by qualified personnel who understand that thermal and mechanical systems have greater inertia (minutes, hours) unlike electronic technology in which the answers are in microseconds. It must make them work harmoniously.
All of the above ensures that the facility remains to provide its services effectively throughout its lifetime.
References
- The Building Commissioning Process and ASHRAE Guideline 0, by Professor Walter Grondzik PE
- Commissioning Course, by Camilo Botero G.
* Camilo Botero is the current 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 has 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.
