Roof air

[miamogue]

I have a 2015 Montana with Dometic air. While away over the winter I ran the air almost every day. Upon returning home I looked at the roof to the rear of the air. There were dark brown streaks that followed the water path that the air ejects. I tried cleaning the stains and after a lot of elbow grease they came out. I then used the air this past week and the beginning of the stains has reappeared. Dometic said they never heard of this. I was wondering if anyone else had this problem and if so what caused it. The air seems to be running ok.
Thank you.

[dieselguy]

A/C has always streaked any roof of any RV I've owned ... applying Aerospace 303 to the roof makes it easier to clean.

[kdeiss]

That is normal becarefull you can do more damage to the EPDM trying to clean it!

[jimcol]

As dieselguy says condensate from the air conditioner always marks the roof. You can remove the shroud and clean the pan with some simple green but it is still going to mark the roof. I just cover the stains with Dawn, rub it in, then wash the roof a cup of Dawn in 4 gallons of water.The stains lighten up but never come completely off. I think rubbing the stains with a stiff brush does more harm to the rubber roof than the stains. Jim

[DQDick]

It's not just the Monty's, if you look at the roof where the condensate runs from the roof air units on our store, you'll find the same thing.

[miamogue]

Thanks all for the information. Will be a lot more careful with the roof from now on.

[Jimmer]

I used the Black streak removal spray and it cleaned it pretty well. I then used 303 Protectant and that worked really well. The roof looks pretty good. I thought about getting some clear plastic that they apply on cars to protect against rock chips but I will see how the 303 works.

[1retired06]

Normal. I just live with it. Scrubbing can be worse for the roof.

[jfaberna]

On a previously owned Class C I damaged the roof beyond repair by cleaning it. With the Montana, I do not clean it. The only ones who see the roof are the folks in planes and helicopters. I spend my time cleaning what I can see. Because the sides are slick from Croftgate Wash and Wax, I rarely see stuff wash from the roof and stick to the sides.

IMHO, nothing in improved by cleaning the roof, but bad things can happen by cleaning it.

[richfaa]

The solution is don't look at the roof. We have never used anything but blue dawn or unscented dish soap on our 6 rv's.

[Clemson1881]

I clean the roof once per year with the Dicor rubber roof cleaner. Dawn is recommended also. The Black Streak Remover on the roof is a big No No! It will damage the roof (contains petroleum).