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When Is it Time to Replace Your Aging HVAC System?


A new HVAC system is one of the most important investments you can make for your business. However, as buildings age, some facilities managers try to stretch the lifespan of outdated systems while still trying to ensure those systems meet the current efficiency standards. As these systems age, structural problems can worsen. Inefficient HVAC systems can increase costs and health, comfort and productivity issues among employees and customers. Use the following factors below to help determine whether it's time to repair or replace your HVAC system.

1. Age

The average lifespan of a commercial HVAC system is approximately 15 to 20 years, depending on several factors, including maintenance, installation quality, climate and weather conditions. According to the U.S. Department of Energy's Energy Star, if your heat pump or air conditioner is over 10 years old or your furnace or boiler is over 15 years old, your HVAC system is likely starting to show its age. You may notice that it used to be more efficient but started breaking down more often. In this case, it's time to consider upgrading certain components or replacing your HVAC system.

2. Energy Efficiency

Energy efficiency is important for your business's bottom line and the environment. HVAC units use a Seasonal Energy Efficient Ratio (SEER) rating to indicate their overall energy efficiency. Generally, the less energy the HVAC system uses, the higher the SEER rating. Air conditioners, heat pumps and packaged systems use the SEER rating scale to help determine the maximum efficiency. While the SEER rating often decreases over time, comparing SEER ratings across units can help determine whether replacing your system is worth it. Additionally, the Department of Energy mandated new energy efficiency requirements and testing procedures on January 1, 2023, for all newly manufactured residential and commercial air conditioners, heat pumps and gas furnaces. New HVAC systems include more environmentally friendly features that older systems don't have, including zoned heating and cooling, energy-efficient controls and Wi-Fi connectivity. If your HVAC equipment doesn't meet the new efficiency requirements, it may be time to upgrade your system.

3. Increased Demand

If you constantly have to adjust the thermostat, it could be a sign your system may be unable to keep up with demand. This could be due to several factors, including occupancy, climate changes or a worn-out system. If your business has grown or changed since you installed your HVAC system, you may need a system with more capacity or one that can handle different air quality challenges.

4. Frequent Breakdowns

If your system is breaking down more often, it's usually a sign that it's nearing the end of its lifespan. Repairs can be expensive and may not be a permanent fix. Frequent breakdowns can disrupt your business operations and cost you money in repair costs. In this case, replacing your system before it breaks down completely is often best.

5. Poor Air Quality

While stuffy, hard-to-breathe air could indicate a possible leak in your HVAC system, it's often a sign that air isn't being filtered through your heating and cooling system correctly. If changing your air filters doesn't help improve the air quality, the problem could be due to damaged ductwork in your building or other issues in your HVAC system. Always consult a professional regarding persistent HVAC issues since a broken furnace can lead to carbon monoxide leaking through the indoor air vents, which can be deadly.

6. Strange Smells

An aging or broken HVAC system can cause musky odors and sometimes burning scents. Strange smells from your HVAC system are a serious sign of trouble and should not be ignored. In this case, indoor air quality may be compromised, putting everyone in the building at risk. Unusual odors often indicate a system failure and require equipment replacement.

7. Unusual Noises

A noisy HVAC system can be disruptive and annoying for employees and customers. Grinding, squealing, hissing, clunking and rattling might mean loose and broken parts. Sudden stops and starts can signal your HVAC system is not getting enough power to operate continuously or is possibly overheating. If your system is making a lot of noise, it may be time to replace it. 

8. Leaks or Excessive Moisture

If you find excessive moisture on walls and windows or spot rust on pipes and appliances, your HVAC system is not working properly. If the problem is serious, your HVAC system will likely need to be replaced.

9. Rising Energy Bills

If you've noticed that your energy bills are increasing, it could be a sign that your HVAC system isn't working efficiently. Higher energy bills could be due to a few factors, including a worn-out system or poor maintenance.

Calculating Repair vs. Replacement Costs

Replacing or upgrading your commercial HVAC system is a big decision, but it can help save you money in the long run. On average, the cost of a new commercial HVAC system ranges from $20 to $33 per square foot depending on the size and layout of your building, the system's energy efficiency, complexity and ductwork.

When deciding whether to keep or replace an older HVAC system, you should consider the ongoing maintenance and upkeep costs, which can get more expensive as HVAC systems age. Even minor repair bills can begin to add up over time and outweigh the cost of purchasing a brand-new, commercial HVAC system. For example, if your HVAC system is not covered by warranty, you'll be responsible for all repair and replacement costs. Repairs can be expensive, so it's important to factor certain components' potential repair costs versus a complete system overhaul into your decision-making process.

Before opting for a new HVAC system, evaluate your current system's downtime record and use a free calculator to find the potential energy savings from investing in a more modern HVAC system. Considering the signs above can help you make the best choice for your business.



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The information contained in this article is intended for general information purposes only and is based on information available as of the initial date of publication. No representation is made that the information or references are complete or remain current. This article is not a substitute for review of current applicable government regulations, industry standards, or other standards specific to your business and/or activities and should not be construed as legal advice or opinion. Readers with specific questions should refer to the applicable standards or consult with an attorney.