Screen door hinge

The screen door hinges on our 2010 Sundance 3200RE have cracked and the bottom one has broken. I will need to replace all of them but I am not sure how! Furthermore, I am not sure why they cracked! Any ideas would be helpful!

My screen door seems like the hinge end hits home before the latch end, resulting in some flex of the hinge. I am expecting that it will break some time in the future.
That may be what is going on with your screen.
I don't know if you will be able to replace just the screen door hinge. If you can it looks like a pop rivet gun and a drill will be needed.
Give Heartland Customer Service a call and maybe they will have a method of replacement.
Or at least they may be able to tell you who made the door. That will give you another contact for information.
Heartland Customer Service
877-262-8032 / 574-262-8030

Peace
Dave