More and more properties now have underfloor heating installed as the most efficient way of providing consistent heat throughout a dwelling or commercial premises. As the pipes are hidden beneath flooring rather than exposed like radiators, one of the best ways of verifying the performance of an underfloor heating system is by using thermal imaging technology. A thermal imaging camera can detect heat patterns through flooring, thereby showing where a system is effective. This is particularly useful when tracing systems in a property, checking newly installed underfloor heating, and detecting problems in existing systems.
Choosing The Right Thermal Imaging Camera
As pipes can be very densely packed in underfloor heating, it is essential to have a thermal sensitivity of <100mK (0.1˚C) and a resolution of at least 160 x 120 pixels in order to clearly see the definition between pipes or variations at the supply-return manifold. A higher resolution of 320 x 240 pixels may sometimes be required depending on the complexity of the system. Suitable models in our range include the FLIR E6-XT and the FLIR E8-XT and more information on our thermal cameras can be found here. We also provide cost-effective hire solutions.
Tracing Underfloor Heating Pipes
A consistent, efficient warming effect throughout a room is achieved by laying pipes under the floor in a regular pattern although practicalities such as hidden obstacles or unusually shaped rooms may require a more complicated pattern. To correctly trace underfloor heating, the user should turn on the system and hold the thermal camera steadily pointing at the floor once it has fully warmed up.
Temperature directly above pipes tends to be at roughly 26˚C compared to an average floor temperature of 18˚C. A working underfloor heating system should be easily traceable from the system manifold, throughout a property and back to the manifold. With autoranging available, a thermal camera will show pipes in bright orange against a purple background when using the 'hot iron' 9k colour palette, as seen in Figure 1.
Figure 1:
Potential Problems in Underfloor Heating
A thermographic inspection can indicate and diagnose a variety of problems within underfloor heating systems. Firstly, a gap in the pattern of pipework suggests that there may be a blockage or leak that is totally preventing warm water from flowing through a certain section of piping. A faint outline of the pipe or ill-defined pattern may also suggest a potential flaw in the surrounding insulation where the pipe is heating the ground rather than the room. Figure 2 is a good example of blocked pipes where large sections of the floor are blacked out because only two pipes are functioning correctly.
Figure 2:
Where there is a partial block or leak, a slightly different pattern may be detected. The bright yellow or white colour of the fully working pipe would tend to slowly fade to just above room temperature as air enters the pipe and lowers its surface temperature. In Figure 3, compare the colour at the point marked ‘M1’ to that marked ‘M2’, indicating colder pipework in middle of the room.
Figure 3:
Finally, a thermal inspection at the system manifold may hint at potential problems in the rest of the system. A large difference between different return temperatures may indicate a potential leak, air ingress, or other malfunctions in various loops of the underfloor heating system. A more general thermographic inspection across the property may then be required to locate and diagnose the problem. Figure 4 shows a thermal image of a manifold. Note the different colours at the ‘M1’, ‘M2’ and ‘M3’ points.
Figure 4:
Conclusion
Whilst a number of varied problems can afflict underfloor heating systems, using a thermal imaging camera provides an all-in-one, non-intrusive method of locating and detecting issues, whether at the manifold or in the actual heating system pipes. By showing heat patterns on screen, the user can also accurately pinpoint remedial work as well as checking the performance of a newly installed system. Thermal imaging technology is now more accessible than ever as we offer a range of powerful thermal imaging cameras for hire from just £95.00 per week.