cats fur loss

[COLOR=red]
My cat appears to be lossing a lot of fur. We have tryed to determin if it because she lays on the heaters. Could this be the cause of this fur loss. It is comming out in clumps. She is also 12 years old.
I hope that i can get some help with this.
Thank you

Heavy hair loss in a 12 yr old could be from thyroid disorder, or other illness.

She needs to see a vet for some tests.