A REPEATABLE METHOD
How to use it
- Create a useful temperature difference: for envelope checks, indoor and outdoor temperatures should be stable and meaningfully different.
- Set or note emissivity and reflected-temperature assumptions; avoid shiny metal and glass when possible.
- Scan a broad area first, then compare the suspect spot with nearby surfaces built in the same way.
- Change the viewing angle. A hot or cold patch that moves with the camera may be a reflection.
- Confirm the pattern with another method such as an air-leakage check, moisture meter or direct temperature measurement.
INTERPRET THE MEASUREMENT
How to read the result
- The color palette is relative to the selected scale; bright colors do not automatically mean dangerous heat.
- Surface temperature is not the same as the temperature inside a wall or pipe.
- A repeatable shape tied to construction details is more useful than one isolated pixel value.
TROUBLESHOOT THE METHOD
Common problems and what to check
Problem
Windows and metal show the room or the operator.
What to do
These surfaces reflect infrared radiation. Change angle or use a nearby matte reference surface.
Problem
The whole image changes color while scanning.
What to do
The camera may be auto-scaling. Lock a sensible temperature span before comparing two areas.
Problem
A cold patch appears only in windy weather.
What to do
Suspect air leakage as well as insulation. Inspect seals and confirm under repeatable conditions.
STOP BEFORE THE HAZARD
Safety boundary
- Keep clear of exposed electrical parts, hot surfaces and moving machinery while concentrating on the screen.
- Do not remove covers from energized equipment just to obtain an image.
- Treat a thermal anomaly as evidence for investigation, not permission to touch or dismantle equipment.
SMART BUYING GUIDE
What to look for when choosing
- Thermal resolution and a focus system usually matter more than a very wide advertised temperature range.
- Choose adjustable emissivity, manual span control and a way to export original images with measurement data.
- A wider field of view helps in small rooms; close-focus capability helps with terminals and small components.
Types of tool
Best for: Occasional surveys when compact size matters.
Best for: Fast whole-room scans at normal distances.
Best for: Small details, electrical inspection and documented comparisons.
Common functions
Thermal sensor resolutionFocus distanceManual temperature spanAdjustable emissivityRadiometric image export
Worth paying more for
- Real detector resolution rather than enlarged display pixels
- Manual focus for terminals and small defects
- Exported images that retain temperature data
Usually not worth the extra cost
- Extreme high-temperature range for ordinary homes
- A large number of color palettes
- Software upscaling presented as sensor resolution