cold spot showing in wall

Does a freon line run inside the wall from the outside unit to the attic units?

A cold spot in the wall is near the ductwork but no cold spot showed on the ceiling where the ductwork is.

Would it be from a freon line that isn’t wrapped properly? In that case, what would one need to have done?

Or, is the metal ductwork the problem - but I can’t see any break in it when I take the vent cover off the ceiling mount and use a mirror to see into the ductwork?

Around here the freon lines go up an exterior wall, inside of it, and they do show up as cold lines on Infrared even when properly insulated. I have found several that are not insulated and are leaking condensation - in the hot part of the summer.

HVAC duct work also shows up as hot or cold depending upon the time of year and what you are running.

uninsulated refrigerant lines and duct leaks with Infrared Thermography technology.

The first thermal image is the interior view of the heat pump refrigerant lines in the wall cavity of the digital exterior view image

The other IR image is leaking or compressed duct work in a vaulted ceiling…most likely an improperly sealed duct leak but only further invasive investigation would be able to determine for sure…condensation/moisture was starting to form on the wall board and verified with a moisture meter at this location


That is often where the hvac objects are in contact with (conductivity heat exchange) with the sheetrock.

As Kevin said, there is condensation concern.
The saturated gas temp in a suction line is 40 degrees F (R-22 unit).
Determine the temp of the spot and see how close you are to this 40F. This may give you an indication if the line is insulated or not. There is also some math we can do to determine if it is insulated or not.

This is one of those times where the Qualitative School of IR does not work.
You can find the spot, but you can’t tell what it is.
With a little more learning we can tell (before cutting into the wall).

I had that was dripping onto the ceiling and causing a wet spot in a dark painted media room. I was able to get close enough to see the gap in the insulation on the freon line in the attic.

Both are pretty common problems around here. If I have some time, I will try and dig up the pictures.