[Avodah] Using an oven for both fleishigs and milchigs

[Eli Turkel via Avodah]

>                                                  If he's permitting them
> to be used for hot drinks as well, he's assuming that we're talking about
> hot pareve tea *after* the meal; the tea is parev, and there's no meat or
> milk to be nivla` at one meal and niflat at the other.  I doubt he'd permit
> a glass used for milchig coffee to be used for hot tea *while* eating meat,
> let alone putting meat in the glass.

> Zev Sero               Meaningless combinations of words do not acquire

Just to be clear Rav Heineman writes

Q: Is china glass?
A: It is customary to consider it as earthenware.

Q: Is corningware glass?
A: No, it is like china.
Q: Can these glasses be used for both hot and cold beverages?
A: Yes.

Q: Can other glass dishes, such as salad bowls or casseroles, be used for
both dairy and meat meals?
A: If the food is cold, or the glass dish is used as a Kli Sheini, it may
be used for both dairy and meat meals. Unless it is used on the oven or
range, a Kli Sheini is okay.

In my experience most ashkenazim use the same glass for milk at a milchig
meal and then wash the glass and use it
for hot tea at (during) a fleishig meal. I doubt if people put in meat into
a drinking glass.
None of my friends drink hot milk.

For a real psak someone can contact Rav Heineman

-- 
Eli Turkel