Problem with thermoscan

[mutzgrila]

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?

[Marc]

The delta T is needed to cause evaporation. Water that evaporates from a surface causes the surface temperature to drop which you can see with the camera, but the camera can see the heat you applied also and that complicates the results beyond interpretation.

The camera has it's limitations. In some situations it's not of any use.

Marc

[mutzgrila]

What could I do to see that watter in the wall using a thermocamera with interior scan?

[Marc]

Turn on either the air conditioner or heating system for that room or for the entire house for a couple hours, then try the camera again. Avoid localized heating or cooling.

There's no guarantee that it will work.

You might have a better chance by using some method other than IR camera.

Marc

[SNations]

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?

You need a temperature difference between the inside and the outside in order to scan the wall for insulation issues. You don't need a temperature difference to look for water. The evaporation of the water creates its own temperature difference, that you then look for with IR.

Or you can let the sun heat the wall, and then let the different heat content of the water show up on IR. This is basically how you'd look for roof leaks.

[Jim Katen]

i used a moisture meter and identified water in part of the wall.

What kind of moisture meter? If it was a pinless model, you might or might not have identified water. Even if it was a pin-type meter, it might or might not be indicating water. Was there other evidence of moisture to corroborate what your meter told you?

Also, were you measuring from the outside surface or the inside surface?

Where do you think the water came from?

I try to see this in a thermocamera when I was doing a inside scan.

This makes me think that you found the water on the outside surface of the wall with your moisture meter and you're trying to see it from the inside with an IR camera - its not likely to work.

I know it's needded a difference of Temperature called delta T, so I heated all the wall. But it doesn?t work.

If the interior surfaces of the wall are not wet, you're not going to see the water no matter how much you heat or cool the wall.

Do I need to heat al the house?s interior or just the wall?

Wich equipment could do that?

I think you're trying to make the IR camera do something that it can't do: see through a wall. It can only tell you the temperature of the surface that you point it at. Nothing more.

PS. What kind of wall construction do you use in Brazil? Is it stud frame construction, like we use in the US or is it masonry or something else?

[kurt]

That's right. Evaporative cooling is remarkably effective at showing conditions. My machine detects down to 1/20th of a degree. It doesn't take much for evaporative cooling to show up on a thermal scan.

OTOH, understand that for IR to be useful, you have to coordinate a lot of things that don't necessarily lend themselves to easy scheduling. Roof leaks are a perfect example. You have to be both diligent and lucky to get the timing and exposures correct for roof leaks to show up in an IR scan.

It's entirely possible that IR won't show you a darn thing even if the interior of the wall is sopping wet.

Every guy I know has IR, but few rely on it exclusively. It's usually easier to look at installation details and figure it out from those. Or, better yet, use IR to tell you where to dig.