Dos and Donts in a fan ventilation retrofit

Today, we are going to give you some tips on HVAC fan retrofit as cooling or ventilation, among a diverse set of functional systems in buildings, accounts for a majority of building energy use (about 60 percent in some buildings) since they are in constant use. When you handle a retrofit project on ventilation fans, it is important to know what one should definitely do, and what not to do.

Do’s:

 

  • Visit the site

 To be able to plan a retrofit, the company implementing it must visit the site to get an idea on what needs to be done. This is the only way to determine how the old fan can be removed from the building, and how the new ones can be installed. On site, it is also easier to determine what kind of equipment and tools can be used and are required.

  • Plan your schedule

Shopping centers or office buildings can often only pause their activity for a short time. Therefore, it is necessary to identify these potential time windows first, and then plan the retrofit accordingly. A detailed schedule should also be created for the conversion itself.

  • Regenerate your documents on the current system

 It is essential to document the desired set-up of the system together with building owners before kicking start the retrofit project. As the existing end-of-life systems can be 20 to 30 years old, it is also important to understand and document the status of the current systems for better planning.

  • Order materials in advance

To ensure the retrofit to be a success, last-minute material procurement should be avoided. There will be no time to purchase materials once the process has started. This applies in particular if the dismantling or installation is carried out on Sundays or public holidays. Therefore, all materials should be procured in advance.

  • Check for control system compatibility

Today, modern fans often have either an analog-based control system, using a 0-10 V signal, or are controlled via a ModBUS interface. In this regard, it is important to check whether these options are compatible with the conditions on site. If this is not the case, a suitable interface should be planned and implemented.

 

Don’ts:

 

  • Do not just focus on the fan

A ventilation system is more than just a fan. While a fan is the important part of a ventilation system, the entire system and its surrounding setups should be considered at design stage of your retrofit project.

  • Do not rely too much on the old building’s documents

Even if there is comprehensive documentation of the system, important key points should be verified again. This can help rule out the possibility that parameters may have changed over time without being documented.

  • Yet, do not ignore documentation

All of the steps in the project must be precisely documented – from agreeing the target set-up through to energy consumption before and after the retrofit. Not only the documentation helps record the project details and system set ups, the recorded data also validate the energy savings benefitted from the retrofit project.

  • Do not plan without applying your eligible subsidies

If your fans are efficient, the retrofit will pay for itself quickly. However, you can recoup the costs even faster if you make use of the available funding or subsidies. So do not forget to do your research and submit your applications on those subsidies.

  • Do not only think about the short term return

You should always look at the long term when assessing a retrofit project. Without a doubt, a retrofit costs money at the beginning. However, over time, you will see impressive cost reduction thanks to the upgraded cost-effective operations and maintenance.

Article by
ebm‑papst Mulfingen (Germany)