Preventive maintenance is a proactive maintenance approach involving inspecting and servicing equipment regularly to help prevent breakdowns by catching problems early on. While closely related, predictive maintenance is a more advanced approach using data and analysis, rather than a preset maintenance schedule to predict when equipment will likely fail. Facility managers and technicians can use thermal imaging inspections in both types of maintenance programs to help address common building and equipment issues. Learn more about how thermal imaging cameras work and can help identify potential problems before they become costly issues.

What is Thermal Imaging?

Thermal imaging uses infrared radiation to create images of temperature differences in a space. Colors are assigned based on the temperature differences the imaging measures, offering a contactless way to access critical components that are too difficult to access for traditional temperature measurements.

Types of Infrared Temperature & Gas Measurement Devices

• Infrared cameras: Point-and-shoot and building diagnostic infrared cameras create high-resolution images using infrared radiation. 
• Firefighter infrared cameras: NFPA-approved thermal imaging cameras are designed with temperature sensitivity and have excellent image quality in low visibility, dark, smoky environments. 
• Infrared thermometers: Thermometers and visual temperature guns are used for finding and troubleshooting hot and cold spots.
• Smartphone infrared cameras:  Compact infrared camera adapters connect to smartphones for convenient, on-the-spot troubleshooting and inspection.
• Fixed location infrared cameras: These are permanently installed to provide continuous monitoring to help prevent equipment failure and service interruptions.  
• Optical gas thermal imaging cameras: Designed for use in the oil and gas industries, these thermal gas imaging cameras use sensors to detect real-time methane emissions and leaks from other industrial gases and compounds.  

Preventive and Predictive Maintenance

From HVAC systems to building envelope inspections, thermal imaging can help detect problems in all types of equipment, including: 

Electrical Systems

Overheating electrical components and loose connections can lead to electrical failures and pose fire hazards. Thermal imaging cameras can identify these issues by detecting abnormal temperature variations, enabling technicians to take action quickly.   

HVAC Systems

Malfunctioning HVAC components, like motors, fans and compressors, can affect energy efficiency and comfort. Using thermal imaging cameras, technicians can quickly pinpoint potential problems, like poor insulation or blocked air vents, allowing for timely repairs and preventing major disruptions. Thermal imaging inspections can also help isolate cold and warm air infiltration issues so that energy efficiency improvements can be made. 

Mechanical Equipment

According to Reliable Plant, heat is often an early warning sign of equipment damage or failure, making it important to monitor. Thermal imaging cameras can help identify temperature abnormalities in mechanical equipment like pumps, motors and bearings. 

Thermal Imaging Benefits

Thermal cameras play a critical role in preventive and predictive maintenance by helping identify subtle temperature variations that may indicate early-stage equipment issues. 

With regular thermal inspections, technicians can:

• Conduct non-intrusive inspections: Unlike traditional maintenance methods that may require disassembly or equipment shutdown, non-intrusive inspections can be done with thermal imaging during normal operations, helping reduce downtime and minimizing operational disruptions. Quicker inspections allow technicians to cover more areas and help identify issues in places that may typically be ignored.   
• Find hidden defects: Thermal imaging cameras enable technicians to identify defects not visible to the naked eye, such as insulation problems, leaks or faulty electrical connections. Addressing these issues proactively can help prevent failures and ensure equipment operates properly. 
• Identify early warning signs: By regularly scanning critical equipment, thermal imaging cameras can detect anomalies that indicate potential equipment failures. These early warning signs allow technicians to address problems before they lead to costly breakdowns or safety hazards.
• Detect leaks:  While a thermal imaging camera can’t directly see moisture or mold in walls, using a thermal camera with a moisture meter can help detect subtle temperature changes. According to Facilities Management Advisor, these temperature patterns can reveal the presence of moisture, which can cause these areas to appear cooler due to evaporation.
• Establish baseline data: Thermal imaging cameras can capture equipment data under normal operating conditions. After repairs are completed, following up with a thermal inspection can help verify a fix was made and critical components are working properly. This data can be a reference for future inspections, making identifying deviations and recognizing developing issues easier. 
• Prioritize maintenance efforts: Technicians can use the severity of detected heat abnormalities to allocate resources efficiently, focusing on high-priority areas that require immediate attention. 
• Improve energy efficiency: Thermal imaging cameras can identify areas of energy loss like poorly insulated walls, air leaks or inadequate piping insulation. By addressing these thermal irregularities, technicians can improve energy usage and reduce utility costs.

Using thermal imaging for predictive maintenance offers a non-invasive way to inspect critical systems and components, potentially saving time and resources, and helping ensure the longevity of important building systems.