Missing Leak - What to do?

[Tin Soldier]

So,

 

I've not previously mentioned that one of my underfloor heating loops leaked.

 

I turned on the underfloor heating for the first time circa a month ago, and after a few hours a wet patch appeared in the concrete slab ( It  happened the second time too.), roughly where I've circled in the picture.

no problem I thought, I know why there would be a leak there.

 

despite trying my hardest not to kink a pipe, I kinked a pipe running the last loop to the manifold, I didn't have time to strip it all off and re do the whole 100m loop, so I took a shortcut, rather than routing through the door way, I had just enough pipe it I nipped it under the built in wardrobe wall in a straight line.

the panel company had been well warned where not to nail, but I guessed someone forgot and stuck a nail in it (and then removed it)

 

 

anyway fast forward to last night, as I trekked home from work with a $6000 Thermal imaging camera to have a look  and see if I could spot where the leak originates/exactly where the pipe is

I had great fun looking at all the loops and happy to see all 10 loops working , warming the floor and house to an uncomfortable level (I set it as high as I could). Great fun as I wait for leak to reappear,

 

unfortunately the leak has not reappeared. no wet patch, not even moist- left overnight, and still nothing.

I'm not sure what to do, where to go form here.

 

The concrete had been down for months before test, and the wet patch was very very localized, so I cant see it being moisture/condensation. It was sopping wet?

 

I surely cant take the risk and floor over it, as it will inevitably leak. any suggestions?

 

 

[Onoff]

I wonder if running it too hot has caused the pipe to expand around the nail or whatever and self seal? Maybe run as normal and try again with the camera?

[nod]

Only way to be sure is dig it out