5 Signs That Your Air-Handling Unit Needs Changing

[edit] 5 watch points for air-handling units

The air-handling unit (AHU) is a critical part of an HVAC system that circulates and conditions the air within a building. Over time, AHUs can experience wear and tear, resulting in decreased performance, higher energy consumption, and potential indoor air quality issues. Recognising the signs that your AHU needs refurbishment is essential for maintaining a comfortable and efficient indoor environment. In this blog post, we will discuss five common indicators that suggest it's time to consider refurbishing your AHU.

[edit] Decreased Performance

One key sign that your AHU requires refurbishment is a noticeable decline in performance. If you experience inconsistent airflow, uneven temperatures throughout the building, or difficulty in maintaining comfort, it may be due to worn-out components or outdated technology in the AHU. Upgrading or replacing critical elements such as fans, motors, coils, and controls during the refurbishment process can help restore its performance.

[edit] Unusual Noises

Unusual or excessive noise coming from your AHU is another indication that refurbishment may be necessary. Rattling, banging, screeching, or other abnormal sounds could be caused by loose or worn-out components, damaged bearings, or imbalanced fan blades. These noises not only indicate potential mechanical issues but can also disrupt occupants and affect their comfort. A thorough inspection during refurbishment can identify and address these noise-related problems.

[edit] Increased Energy Consumption

A sudden increase in energy consumption without any changes in occupancy or usage patterns might be a sign that your AHU is operating inefficiently. Aging components, outdated controls, and inefficient fan systems can contribute to higher energy usage. Refurbishing the AHU presents an opportunity to upgrade to energy-efficient motors, install variable frequency drives (VFDs) for fan speed control, and implement advanced control strategies to optimise energy usage, leading to long-term energy savings.

[edit] Poor Indoor Air-Quality

The AHU plays a critical role in maintaining indoor air quality (IAQ) by filtering and conditioning the air before distributing it throughout the building. If occupants experience more allergies, respiratory issues, or a decline in air quality, it could be due to a compromised AHU. Over time, filters can become clogged, moisture can accumulate, and microbial growth can occur, resulting in poor IAQ. Refurbishing the AHU involves inspecting and replacing filters, cleaning coils, and addressing underlying issues to ensure a healthier and more comfortable environment.

[edit] Age & Lack of Maintenance

Lastly, the age of your AHU and its maintenance history are crucial factors in determining if refurbishment is necessary. Older AHUs that have not received proper maintenance are more prone to performance issues and inefficiencies. Even without specific signs, it's advisable to consider refurbishing older AHUs to improve their reliability, performance, and energy efficiency. Regular maintenance and inspections can help identify potential issues early on, preventing costly breakdowns or replacements.

[edit] Conclusion

Recognising the signs that your AHU needs refurbishment is vital for maintaining optimal indoor air quality, energy efficiency, and occupant comfort. If you observe decreased performance, unusual noises, increased energy consumption, poor IAQ, or have an aging AHU without regular maintenance, it's time to consider refurbishing the unit. By addressing these issues through refurbishment, you can enhance the AHU's performance, extend its lifespan, and ensure reliable operation, leading to a healthier and more comfortable indoor environment. Consult HVAC professionals to assess your AHU and plan the necessary refurbishment steps.

--Building Ventilation Solutions

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Comments

An air-handling unit (AHU) is a critical component of HVAC systems that is responsible for circulating and conditioning air in a building. Regular maintenance and monitoring are essential to ensure the AHU functions properly. Here are five signs that your air-handling unit may need to be replaced:

1. **Age of the Unit**: AHUs have a limited lifespan, typically ranging from 10 to 20 years depending on the quality of the unit and how well it has been maintained. If your AHU is approaching or has exceeded its expected lifespan, it may be time to consider replacing it. Older units are more prone to breakdowns and may be less energy-efficient.

2. **Frequent Breakdowns**: If your AHU requires frequent repairs or experiences recurring issues, it could be a sign that the unit is nearing the end of its serviceable life. Continuous breakdowns can result in higher maintenance costs and discomfort for building occupants.

3. **Inefficient Performance**: An aging AHU may struggle to maintain consistent indoor temperatures and air quality. If you notice that your HVAC system is no longer providing efficient heating or cooling, or if energy bills have increased significantly, it might be due to the declining performance of the AHU.

4. **Excessive Noise or Vibration**: Unusual noises, vibrations, or rattling coming from the AHU can indicate mechanical problems, worn-out components, or imbalanced parts. If these issues persist despite repairs, it could be a sign that the AHU is deteriorating and needs replacement.

5. **Rising Maintenance Costs**: As AHUs age, their maintenance requirements tend to increase. If you find yourself spending more on frequent repairs, replacement parts, and service calls, it may be more cost-effective in the long run to invest in a new AHU that is more reliable and efficient.

Before making a decision to replace the AHU, it's a good idea to consult with HVAC professionals. They can assess the condition of the unit, diagnose any issues, and provide recommendations based on your specific situation. In some cases, it might be possible to perform certain repairs or upgrades to extend the life of the AHU, but if the unit is consistently underperforming and causing discomfort or increased costs, replacement may be the best course of action.