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mutzgrila mutzgrila
11-16-2014, 07:31 AM
i used a moisture meter and identified water in part of the wall.
I try to see this in a thermocamera when I was doing a inside scan.
I know it's needded a difference of Temperature called delta T, so I heated all the wall. But it doesn´t work.

Do I need to heat al the house´s interior or just the wall?
Wich equipment could do that?

Brian Hannigan
11-16-2014, 07:38 AM
Hello mutzgrila mutzgrila,

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Scott Patterson
11-16-2014, 08:20 AM
i used a moisture meter and identified water in part of the wall.
I try to see this in a thermocamera when I was doing a inside scan.
I know it's needded a difference of Temperature called delta T, so I heated all the wall. But it doesn´t work.

Do I need to heat al the house´s interior or just the wall?
Wich equipment could do that?

It might be the camera. What brand and model camera are you using?

If you can post a picture of the wet wall that might help others to provide some help.

Jerry Peck
11-16-2014, 08:23 AM
I try to see this in a thermocamera when I was doing a inside scan.
I know it's needded a difference of Temperature called delta T, so I heated all the wall. But it doesn´t work.

Do I need to heat al the house´s interior or just the wall?
Wich equipment could do that?

You destroyed the evidence (so to speak) for the infrared camera to see by heating the wall - the infrared camera is looking for temperature differences, and heating the wall removed those temperature differences you were looking for.

Scott Patterson
11-16-2014, 08:32 AM
You destroyed the evidence (so to speak) for the infrared camera to see by heating the wall - the infrared camera is looking for temperature differences, and heating the wall removed those temperature differences you were looking for.

It could also be that the moisture meter provided a false positive. Maybe a piece of metal, nail, screws, wire, nail plate, etc... The wall might not have any moisture in it!

Steven Turetsky
11-16-2014, 09:11 AM
Heating the wall can sometimes help locate moisture (with a thermal cam).

As stated; you are measuring temperature [temperature differentials] and everything changes temperature at a different rate, water being the slowest. So if there is a wet area in the wall, and you turn up the heat in the room, the wet areas will change temperature at a different rate of speed then the dry areas.

If the water has been in the wall for a while, it has the chance to equalize temperature with the wall. By changing the temperature of the wall, you are creating a differential.

How did you heat the wall? How long did you wait when heating the wall? How did you identify the wet areas with a moisture meter? (surface scan or probes).

Jerry Peck
11-16-2014, 09:14 AM
How did you heat the wall? How long did you wait when heating the wall?

Those are the questions I was thinking of ... but did not ask ... as they will either (as you said) help find the issues (like the sun heating a wall - the interior parts of the wall show up better) or remove the evidence by bringing the entire wall structure to the same temperature (which is what I was suspecting he did) and this no differences show up.

Steven Turetsky
11-16-2014, 10:45 AM
Those are the questions I was thinking of ... but did not ask ... as they will either (as you said) help find the issues (like the sun heating a wall - the interior parts of the wall show up better) or remove the evidence by bringing the entire wall structure to the same temperature (which is what I was suspecting he did) and this no differences show up.

I agree, there are unanswered questions. Assuming the wall is wet, I wonder what in the area could be contributing since there are other enhancements that may be helpful.


i used a moisture meter and identified water in part of the wall. I try to see this in a thermocamera when I was doing a inside scan.

How did you do this? Maybe the problem is not the cam, but the meter.




I know it's needded a difference of Temperature called delta T, so I heated all the wall. But it doesn´t work.
Do I need to heat al the house´s interior or just the wall?
Wich equipment could do that?

You only heated one wall? How did you do this?

If I was conducting that test, I would heat the whole house and would use the house's heating system to do this. If there was no heating system, I would heat the whole room using some type of portable heating system. Depending on the conditions, normally in about 1/2 hour I would start scanning, and again in 1/2 hour increments until I was satisfied.

Depending upon the conditions, I may ask a client to blast the heat 1/2 hour (or so) before I arrive.