Problem:
Recently, Trackie was asked to inspect a multi storey apartment block where the ventilation fans on the roof of the building were creating quite a racket! So much so that the residents of this building had taken drastic measures such as climbing onto the roof to turn the fans off. They were clearly frustrated as this is a big no, no.
As it turns out, the fans at this property were noisy, worn out and were at the end of their service life (15 years old). Coupled with high energy consumption, these fans needed to go.
Solution:
One solution would be to replace the fans like for like, however, this would reduce the noise but the energy costs would remain quite high. Instead, there is an energy efficient solution that is whisper quiet and comes in the form of an Electronic Commutated (EC) fan. By replacing these fans with EC fans, energy consumption will be slashed because they use less than half the energy of the traditional fans! How is this possible you ask? Well, it’s because fan speeds can be reduced by 75% which equates to fans being nice and quiet while at the same time, maintaining accurate air flows.
What’s involved in the rectification process?
Step 1: Involves entering each apartment to carry out air flow pre reads. This process reveals the current air flow position within each apartment. Some apartments are likely to have minimal air flow while others have high levels of air flow.
Step 2: Mechanical drawings are analysed to identify which fans serve which apartments, how many inlets there are and finally, the required air flow for each inlet. These calculations provide figures for total air flow requirements in the building. This coupled with duct length and static pressure provides the information required to design the fans for the specific building. Its’s usually the case that fans are slightly oversized so that they can be slowed down for extra efficiency.
Step 3: Once the fans are installed, each apartment will need to be accessed a second time to balance the air flows as per the calculations. Once complete, the residents will enjoy adequate ventilation/air flow, peace and quiet and finally, reduced energy consumption.
In summary, the fan rectification process involves taking air flow pre reads, engineering energy efficient EC fans, installation of new EC fans and finally, balancing the air flows so each apartment receives the air flow, as well as the peace and quiet they deserve. So next time you see someone climbing onto the roof of an apartment building to turn off the fans, maybe it’s a sign that it’s time to get them checked out!