This is how we automate an HVAC system

Automating an old HVAC system not only provides the flexibility to operate the air conditioning in different zones but also improves the energy efficiency thereby reducing the electricity bill. This is what we were able to achieve when we undertook the task of automating an old HVAC system in one of the embassies in New Delhi. The embassy had its HVAC system installed in 2003. Therefore, it goes without saying that the system was too simplistic for today’s needs. There was a 100 TR chiller plant. ‘Mild Steel piping work’ supplied chilled water to the AHUs. The AHUs conditioned the air and through ductwork, the chilled air was distributed to different rooms, zones in the building. Very straightforward. All that meant was an AHU distributing conditioned air to different rooms and halls supplied constant CFM of air volume at constant temperature to different rooms. Whether someone in one room desired a higher temperature or someone in another room desired a lower temperature or someone didn’t need the air conditioning at all, all these features were not there. In a nutshell, there was no flexibility to the users. The HVAC system delivered constant air volume at constant temperature to all the rooms and zones. If someone was feeling cold, he or she would ask the attendant to switch off the AHU. This would irritate the other occupants sitting and working in different rooms.The whole process had become an irritant for a number of years. Something had to be done. The embassy reached out to TheSmartHVAC team. The situation was explained and what was needed was explained. TheSmartHVAC team gathered the requirements and surveyed the whole building. The administration of the embassy had put some constraints that no changes should be made in the AHUs or ducting, no alteration should be done in the civil work. In other words, no replacement of the existing equipment, and no breaking of walls or ceilings. The task was challenging.

Design

TheSmartHVAC with its in-house team of design engineers brainstormed hard and came up with an innovative solution to convert an old constant air volume HVAC system at the embassy into a variable air volume HVAC system. Without making any changes in the existing AHUs or changing the ducting work, the team made use of the volume control dampers, actuators, controllers, sensors, and variable frequency drives. A comprehensive plan was submitted to the embassy. And the plan was approved because not only it improved the flexibility and energy efficiency but also it was within the embassy budget.

Installation

As soon as the plan was approved, TheSmartHVAC placed the orders for volume control dampers, actuators, controllers, sensors, wiring, and drives. Now, it was time for the execution. The execution team prepared an execution plan and the first stage in the execution was the replacement of old manual dampers and grills with new volume control dampers and newly designed aesthetic aluminum extruded grills. The team encountered a challenge. The challenge was to fit the new volume control dampers in the duct openings. There was neither a room or space to firstly insert the dampers nor to maneuver the tools. Therefore, the only option available was to cut the false ceiling by a foot on each of the 4 sides. The permission was sought from the embassy. As soon as the permission was granted by the administration department, the team quickly got into the action and started to cut the false ceilings. This whole process extended the project timeline. The false ceiling cutting work took 4 working days as there were several duct openings across the whole building. Once the false ceiling openings were enlarged, the team started removing the old manual dampers and new volume control dampers were installed across the whole building. Thereafter, actuators were installed on the shaft of each and every volume control damper. The actuators were tested. The actuators were satisfactorily able to apply the necessary torque to open and close the volume control damper blades. Now, the next stage was to install the controllers and temperature sensors. The temperature sensors with a display panel and various other features such as setting the temperature, switch on/off button were installed at a convenient location in each and every room and hall across the building. The controllers were installed adjacent to the actuators. These controllers would take signals from the temperature sensors and accordingly instruct the actuators to open or close the volume control dampers. Additionally, the controllers would also send signals to variable frequency drive panels that were installed adjacent to the AHUs. The whole installation of actuators, controllers, sensors, and drives along with the wiring work was a man-hour intensive task. The team worked late nights for several days. The goal was not to disturb the daily working hours of the embassy staff. Therefore, the time slot available to implement the whole solution was available from evening to late night. The installation process was completed as per the design. Right design and planning meant that there were no hiccups or rework during the installation phase. Now, it was time for testing.

Testing

The administration department checked each and every room and hall. They were clearly able to switch on/off the air conditioning in each and every room and hall. As soon as they pressed on the switch off button, the controller would send a signal to the actuator to close the damper. Additionally, the controller would also send a signal to the variable frequency drive panel to accordingly slow down the AHU. Likewise, the administrative staff was able to set the desired temperature in each and every room and hall. If the desired temperature was set to be 22 degrees, and as soon as the room or hall temperature touched 22 degrees, then, the controller would send a signal to the actuator to close down the damper. At the same time, the controller would send a signal to the variable frequency drive panel to slow down the AHU accordingly. The whole system was tested for a week. The false ceiling cuts were refilled. And the new fully automated HVAC system brought smiles and satisfaction to all the staff members of the embassy.

TheSmartHVAC team successfully converted an old constant air volume HVAC system into a new variable air volume system. Not only did the new system provide flexibility to each and every room and hall but also the new system reduced the energy consumption for the whole HVAC system.

TheSmartHVAC with its focus on energy efficiency undertakes HVAC automation projects across India.

The team is adept at converting any old HVAC system into a fully automated system. TheSmartHVAC is working with some of the hospitals, hotels, airports, warehouses, office buildings, cold storages, malls across India to automate their existing HVAC system.

Are you a building owner or building manager or facility manager or administrative staff? Get in touch with us to automate your HVAC system in order to reduce energy consumption. Write to us at [email protected]