What is a PHE thermographic survey?
A thermographic survey is a preventative maintenance technique that uses infrared imaging to assess the external temperature profile of a plate heat exchanger (PHE). Abnormal temperature patterns can indicate internal issues such as fouling, blockages, restrictions or leakage.
- Non-invasive inspection (no dismantling)
- Early fault detection to reduce unplanned downtime
- Actionable findings and recommendations
How does thermography assess a plate heat exchanger?
Infrared cameras and thermograms
Thermal imaging cameras measure infrared radiation and create a “thermogram” showing heat distribution across the heat exchanger surface.
Analysing temperature variations
Because heat flows from warmer to cooler areas, the surface temperature profile provides clues about internal performance. Deviations from expected patterns can highlight flow issues, restrictions, or reduced heat transfer.
Passive vs active testing
Surveys can be completed using passive testing under normal operation, or active testing where appropriate by introducing a thermal contrast to reveal issues not always visible during passive inspection.
What issues can a thermographic survey detect?
- Fouling & scale build-up (insulating deposits that reduce heat transfer)
- Blockages & restrictions (poor/no flow areas and uneven temperature profiles)
- Internal leakage (unexpected mixing between channels impacting temperature patterns)
- Flow maldistribution (inconsistent performance across the plate pack)
- Early gasket-related indicators (where external leakage affects local surface temperature)
Benefits of PHE thermographic surveys
- Minimise downtime by diagnosing issues without dismantling
- Prevent failures with early detection and proactive maintenance planning
- Improve efficiency by identifying heat transfer losses and underperforming areas
- Support safety and reliability through condition monitoring and clear recommendations
Why choose Moody Heat Exchangers?
- Specialist support for plate heat exchanger inspection and performance issues
- Clear thermographic findings and practical next steps
- UK-based service
- Supply and support all brands of PHE
Book a thermographic survey
To discuss your plate heat exchanger thermographic survey requirements, complete the below form and our team will get in touch.
- Phone: 01777 701141
- Email:
Find out about our other products and services: moodyheatexchangers.com.