"Vox Humana" wrote in message
...

I find that the only thing that will clean the gray grates is oven
cleaner.
I put them in a garbage bag, spray with heavy duty oven cleaner (yellow
can), and let them sit all night. I find that the odorless oven cleaner
in
the blue can doesn't work well. You can generally just rinse them off in
the morning.

Thank you for the cleaning tip. I will give that a try.