Hi Kathy and welcome
After reading all the replies, I sense that some folks don't like dens
I, on the other hand, have a large number of them. If yours has the name Burana in it, it likes high light so I don't think it'll turn out to be sunburn. It would be very helpful to be able to see a picture.
I had/have a Den Zengyo Pink that decided it wanted yellow leaves last year...here's a link to my original post on it:
Baffled!
and here it is two months ago:
http://www.orchidboard.com/community...077&ppuser=293
Don't be afraid to experiment a bit...and don't let the den-phobics scare you away from them