Thermal Imaging of radiant heating leak


The blob in this thermogram is caused by a water leak in a radiant heating line. These heating coils were embedded 4 inches into the concrete floor slab. Infrared inspection accurately located this very small, slow leak.

Water leaks in radiant heated floors can damage a floor’s surface and the building’s structure. An undetected leak can lead to rot, mildew, mold and insect infestations. A leak in radiant heated floors and ceilings will allow air to enter the system causing noise; reduced circulation rates and will lower heating system efficiency. Electrical shorts in electrically heated floors can cause fires and open circuits fail to provide heat to all or part of a room.

Our high-resolution thermal imager will pinpoint the location of a leak, short or open connection in the radiant heating system. We then mark the floor in that exact spot and because thermal imaging is so accurate, it allows the contractor to fix the problem with minimal damage to surrounding floor areas.

Infrared radiant floor infrared inspection is fast, non destructive and prevents unnecessary and random digging of your floors to “find” the problem. An infrared scan of your radiant heating system can also detect circulation problems such as defective valves and circulation pumps.


Infrared thermography is well suited for the detection of radiant heating elements and other sub surface heated piping. Defects in embedded conduits that carry heated fluids, gases or electrical heating lines can be difficult to pinpoint and often require costly and destructive exploratory digging. This excavation process is often ineffective, as there is no guarantee that the digging is occurring in the exact area of the defect. In retrofit construction, buried heating conduits in the work area must be located and marked prior to cutting or drilling into the substrate.

The usual practice for the thermographic inspection of subsurface radiant heating lines is to start the floor at ambient temperature, turn the heat on, and image as the heat signature first develops on the surface of the floor. At this point, the ideal situation would be a well-defined narrow heat signature, which allows for pinpointing the location of the heating pipe. As the floor warms up and the flooring materials begin to saturate with heat, the thermal signature spreads horizontally through the materials, yielding a wider signature. Once the flooring is saturated with heat, it becomes more difficult to identify the exact center location of the pipe. In some cases, the thermal signatures from adjacent heating lines will begin to bleed together resulting in a thermogram with very low thermal contrast between pipes and little to no unique signature at the pipe’s center.

Thinner floors will image differently than thicker floor substrates because of the horizontal heat spread through the substrate. In a thick floor there is increased distance of the heating pipe, which is usually located near the bottom of the substrate material to the floor’s surface. Because of the larger distance the heat must conduct through, there is more opportunity for it to spread horizontally as it is conducting vertically to the surface. This results in in an initial heat signature which may be significantly wider than what is seen on a thinner floor. As the floor warms up, signatures may bleed together reducing the high thermal contrast area between the pipes, and making it more difficult or impossible to isolate individual heating lines and to pin point their center locations.

The ability to identify the exact location of a radiant pipe or electrical mat or to find a small hot spot or leak in a radiant heating system depends solely on knowing how to achieve a clear thermal image of the defect. The skills set required to image the many different floor types in order locate these heating lines and their associated defects makes infrared radiant heat leak inspections one of the more challenging infrared applications. 

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