HELP!! with Sun Touch Heating Mat

[c2500]

Ok,

Yesterday I installed 3 mats. One in one bathroom, 2 in another. Followed the instructions and made resistance readings. All were fine and within tolerance. Self leveling compound was poured over them. A rubber squeege was used to spread it, so no fear of a trowel nicking wires. This morning, two of the mats were fine, with identical measurements. The third mat had an increase of 11. Sun touch engineer said it was a kink. Removed the wiring to the point it hits the mat. Was getting very wild readings.

Then made a discovery. Part of the bathroom has no heated space below. It is the ceiling for a porch below. This area still appears wet relative to where the other matts are located. The portion of the mat that has conditioned space below is much dryer looking. When I walk (in socks due to newly finished floors) over the dry looking area, the reading is stable. When I walk over the damp looking area, the readings go haywire. Going as high as 100 or as low as 21. The end of the mat is located in this area.

Has anyone heard of this? There is no evidence of a kink because you can see the where the wire is through the leveling compound. The only odd variable is water. I think the tip may not have been sealed well and water is in the wire.

Also, there is no reading from black or white to ground.

Your thoughts?

c2500

 

[LarryFine]

Since even the low end of the variable reading is above that of the other mats, you have an intermittent open in the cable. You need to locate the damaged spot of the inner heating conductor, which may not be visible to the eye.

The wetness of the mud likely has nothing to do with this issue. If it did, your testing would indicate a leakage current to ground. You may be able to repair the cable, but at who's expense? Good luck.

 

[c2500]

It is so strange that I can stand on an area of 5 sq ft or so and the reading drops down to as low as 21...I need 20. There should not be any deflection, and the leveling compound is rigid. And for those that may ask...there is a loud mouth there for the tile installer. Since I was in control of the leveling compound and was very careful, it was not used for this portion of the install.
I am not sure how the blue wire is assembled under the sheathing, so I still wonder if moisture is the culprit.

c2500

 

[LarryFine]

And for those that may ask...there is a loud mouth there for the tile installer. Since I was in control of the leveling compound and was very careful, it was not used for this portion of the install.

You're supposed to have it connected any time you're doing anthing to the mat, so you know real-time exactly when you encounter or cause a break in the wire.

You had it disconnected exactly when you needed it. You might have discovered the break the first time you touched or flexed that particular section. Oh, well.

 

[c2500]

Well, I guess this would be the 5% time that the loud mouth would have missed the problem. (The literature says it works 95% of the time) It would not have triggered until hours later (as best I can tell), as the tip was very well secured.

It turns out after much dancing on top of a mat, that the factory finished end was defective. In fact, Suntouch has requested it back so they can investigate why it failed. They also said they will cover the repair cost. In one postion it read 18.9. Shift it slightly it increased to 30 then continued up until the connection was broken. The Suntouch guy said moisture could have been an issue, but doubted it.

The vibration when the mat was set in the mortar caused the reading to change ever so slightly. So from yesterday afternoon to this morning the resistance increased by 11.

The lesson learned......While installing, giggle the factory finished ends and check for a resistance change.

c2500

 

[c2500]

You're supposed to have it connected any time you're doing anthing to the mat, so you know real-time exactly when you encounter or cause a break in the wire.

You had it disconnected exactly when you needed it. You might have discovered the break the first time you touched or flexed that particular section. Oh, well.

Larry,

Under any other circumstances, I would agree with you. However given the long cure time (best guess 18 hours) and the fact the tip was so well secured, it would not have helped...in this situation. The curing of the leveling compound is what brought the problem to light. If I had gone over this morning with the loud mouth going off, I still could not have done anything different.

c2500

 

[mdshunk]

The lesson learned......While installing, giggle the factory finished ends and check for a resistance change.

I guess you could do that, but all the one's I've ever installed have been super-reliable. I've never had a single failure of any brand of underfloor heating mat or heating cable that wasn't knicked by the tile guys, and that was only twice.

 

[c2500]

I guess you could do that, but all the one's I've ever installed have been super-reliable. I've never had a single failure of any brand of underfloor heating mat or heating cable that wasn't knicked by the tile guys, and that was only twice.

Well, leave it to me to find one :smile:. I have a nack for that type thing. I am impressed that Suntouch stepped up to the plate and will cover the repair. The guy said they rarely have issues, and I believe him.

c2500