You don't mention the age of the a/c but many do show age issues after about 10 years.
I would just bite the bullet and pull it off the roof and get it bench tested and repaired. The plus side to that is you can replace the roof gasket with a new one at the same time. The roof gaskets are generic and readily available at any RV parts shop.
And Yes, 11,000 is a bit small for a 25'er, 13,500 would do a better job with that much area, esp in Texas, where everything has to be bigger (LOL)