Brahmas are a cold hearty bird. They get hot easily due to their size and extra feathering on the feet.
While panting is normal, be sure they have a shaded place to cool down in. And make sure they actually cool down. They shouldn’t be panting all the time, but in the sun or exerting themselves sure.
Is the coop hotter than ambient temperature or cooler?
They have a huge barn which is cooler than the outside. Then they have a covered area which is still protected from weather and critters then they have a netted area so they can go outside and enjoy grass worms etc. we let them out everyday. They have panted in all places. My guess was the heat. A great big monster fan is on the way. They were rescued from a very small area so I just wanted to make sure they were not sick. Thanks for all your help. Our chickens are all named and loved.
I also use shallow pans of water, such as pig pans in the shade for them to stand in to cool off. Fans that blow out of the coop to pull cool air inside are good as well. My brahmas were the ones who were more prone to heat. They were sit and pant with beaks open and wings held out from the body.