Another been there done that!!
I tell moms that I did (more than once) forget that I had parts on the stove.
It makes me appear as someone who has "been thru it" -and I have. I tell them
to put a washcloth in the pan under the parts. That way if the water boils
away hopefully they will smell the washcloth singeing before the parts melt.
(lets face it  washcloths are cheaper to replace than pump parts - and they
don't smell quite so bad when they burn)

Cheryl L. Tompkins CLC