Energy-efficient building with glowing air-handling units.

Is Your Building Wasting Energy? Simple Checks to Slash Costs Now!

Lena Kashyap in Climate & Environment June 2025 • 4 min read.

"Discover how to identify and fix hidden energy faults in your building's air-handling system, saving thousands on your energy bill."

Did you know that buildings account for approximately 40% of the total energy consumption in the United States? A substantial portion of this energy is often wasted due to inefficiencies and faults within building systems, particularly in heating, ventilation, and air conditioning (HVAC) systems. Faulty operations can account for approximately 20% of a building's energy consumption, but with smart strategies, significant savings are within reach.

Identifying and addressing these faults can lead to substantial cost savings and improved sustainability. Advanced fault detection methods and software tools are now available, that help building managers quickly pinpoint and rectify issues that lead to energy wastage. By implementing these solutions, buildings can operate more efficiently and reduce their environmental footprint.

This article explores practical methods for detecting common faults in air-handling units (AHUs), which are central to building energy efficiency. We will cover how to spot issues like simultaneous heating and cooling, imbalanced airflows, and heat recovery pump malfunctions, offering actionable insights to optimize your building's energy performance. So, let's dive in and unlock the secrets to a more energy-efficient building!

Spotting Energy-Wasting Faults: A Practical Guide

Energy-efficient building with glowing air-handling units.

Detecting faults in air-handling units (AHUs) requires a systematic approach that combines an understanding of HVAC principles with careful monitoring and analysis. Here are some common faults and how to identify them:

Simultaneous heating and cooling is a common issue where the AHU is both heating and cooling the air at the same time, leading to significant energy waste. This often happens due to control system errors or malfunctioning valves. Early detection and correction can lead to considerable savings.

Check Temperature Sensors: Ensure that temperature sensors are accurately measuring the air temperature at different points in the AHU. Inaccurate readings can trigger simultaneous heating and cooling.
Monitor Valve Positions: Verify that the heating and cooling valves are operating correctly. If both valves are open simultaneously, it indicates a fault.
Analyze Energy Consumption: Compare the actual energy consumption with the expected levels. A significant deviation can signal a problem.

Faulty sensors can provide incorrect data to the control system, leading to inefficient operation. Regularly calibrate and maintain sensors to ensure accurate readings. Heat recovery systems can significantly improve energy efficiency by preheating or precooling the air. Regular checks and maintenance can ensure they operate effectively, maximizing energy savings.

Take Control of Your Building's Energy Future

By implementing these fault detection strategies, building managers and owners can achieve significant energy savings and create more sustainable environments. Addressing common issues such as simultaneous heating and cooling, faulty sensors, and heat recovery pump malfunctions can lead to substantial reductions in energy consumption and costs. Embracing new technologies and methodologies not only improves operational efficiency but also contributes to a greener future. Stay informed, stay proactive, and make a positive impact on your building's energy performance.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

Everything You Need To Know

How can I determine if my building's HVAC system is wasting energy?

To determine if your building's HVAC system is wasting energy, start by checking for common faults in the air-handling units (AHUs). Look for issues like simultaneous heating and cooling, where the system is both heating and cooling air at the same time, which can occur due to control system errors or malfunctioning valves. Also, verify that temperature sensors are accurately measuring air temperatures and that heating and cooling valves are operating correctly. Comparing actual energy consumption with expected levels can also signal a problem.

What is "simultaneous heating and cooling" in an AHU, and how does it waste energy?

"Simultaneous heating and cooling" is a common fault in air-handling units (AHUs) where the system is heating and cooling the air at the same time. This typically happens due to control system errors or malfunctioning valves. It wastes energy because the system is essentially working against itself, consuming energy to both heat and cool the same air stream. Addressing this issue through early detection and correction of valve or sensor problems can lead to significant energy savings.

How do faulty temperature sensors impact the efficiency of air-handling units (AHUs)?

Faulty temperature sensors can provide incorrect data to the control system of air-handling units (AHUs), leading to inefficient operation. Inaccurate readings from these sensors can trigger issues like simultaneous heating and cooling or prevent the system from responding correctly to changes in environmental conditions. Regularly calibrating and maintaining sensors is crucial to ensure accurate readings and optimal energy efficiency.

What role do heat recovery systems play in building energy efficiency, and what maintenance do they require?

Heat recovery systems play a significant role in improving energy efficiency by preheating or precooling air, which reduces the load on the heating and cooling components of air-handling units (AHUs). Regular checks and maintenance are essential to ensure these systems operate effectively. Maintenance includes verifying proper airflow, cleaning heat exchange surfaces, and ensuring that pumps and controls are functioning correctly. Malfunctions in heat recovery systems can lead to reduced energy savings and increased energy consumption.

What advanced technologies or methods can building managers use to identify energy wastage in air-handling units (AHUs)?

Building managers can use advanced fault detection methods and software tools to quickly pinpoint and rectify issues in air-handling units (AHUs) that lead to energy wastage. These tools can analyze real-time data from sensors and control systems to identify anomalies, predict potential faults, and optimize system performance. Implementing these solutions enables buildings to operate more efficiently, reduce their environmental footprint, and achieve substantial cost savings. Continuous monitoring and analysis, combined with proactive maintenance, are essential for maximizing energy efficiency.