I installed a tiled floor about a year ago with an electric underfloor heating mat. Base is a concrete floor with 10mm tile board insulation, deep adhesive bed on the heating mat, with a ceramic floor. I had an electrician come and complete the heating mat test and wire the thermostat to the heating mat and install a fused spur. System worked fine up until about 3 weeks ago when a hot spot developed around a 2 sq. mt. area of floor - the rest of the floor being cool - with hot spot temperature rising to a point where you cannot leave your hand on the floor. Got back in touch with the manufacturer and they suggest an installation error - either crossed wires or an air void - but I installed it myself along with 4 other heated floors and know that all was done to specification. Any ideas as to cause? Alternatively, what tests could be done to narrow down the possible causes? Thanks in advance.
