discolored ceiling

[Zigpep]

Hello, when we bought our rv i know i really looked at the ceiling
however we have had it for only about 10 days and i just noted an issue. The interior ceiling is a carpet like or cloth material (not vinal). While I was packing up the rv for our first trip this week I noted very faint outline stain, almost like a sweat stain on the ceiling that extended about 2 feet to the front and sides of the
ac vent in the interior roof. The entire area is not discolored, just a faint tannish outline. Ceiling does not feel mushy or damp and we have had a couple of rains and checked the interior of the rv every time and did not see any leaks.
After I noticed the stain we removed the interior cover over the rv vent while the ac was on and we could feel some slight condensation dampness. We also checked the small amount of the wood framing we could see at the ac under the cover and it shows no signs of water issues or discoloration.
Should we be concerned about a leak or sould this just be slight discoloration from ac condensation? It is possible it was there when we bought the rv, the outline is very faint and shows up in certain lighting only.
The exterior roof is fiberglass and seems to be in good shape.

Thanks zigpep

[dcason]

We bought a moisture meter to probe into anywhere we wish in our class c and it has helped immensely in finding condensation issues and outright leaks (argh).

[Roy_Lynne]

We had the same thing. It was around all the vents and AC, we used a carpet cleaner and it did a pretty good job but when we took it to our mechanic he said he could clean it and DID. Don't know what he used but its white as snow now.

[Bordercollie]

I noticed a small rectangular grayish area in our rig's white ceiling fabric which I think is caused by an opening in the foam plastic air conditioner ducting. The darkened area is not damp and appears to be caused by air flow.

[bdpreece]

Remove the inside cover and snug down the 4 bolts that hold the air conditioner to the roof. Do not over-tighten them as it will ruin the gasket.

[Zigpep]

Thanks for the reply. I do know that when the ac is running there is
water that runs off the roof. We will check and see. If it was a serious leak would we not see more staining? And yes I know all leaks in an rv can be serious, I am just hoping we have not missed a significant issue.
Thanks again, zigpep

[Sandia_Man]

Looks like it did come from AC condensation which should drip out unto your roof unless drip pan is clogged, once pan is full will cause condensation to overflow and drip inward. Also need to check tightness of AC as they can get loose and condensation could get past gasket.

[midnightsadie]

yep it was most likly there ,you just missed it, now find out where and why its there,