CLN: clean up internal impl of fillna/replace, xref #11153

Author: jreback

doc/source/whatsnew/v0.17.1.txt

@@ -72,9 +72,13 @@ Bug Fixes
 
 - Bug in ``HDFStore.select`` when comparing with a numpy scalar in a where clause (:issue:`11283`)
 
+
 - Bug in tz-conversions with an ambiguous time and ``.dt`` accessors (:issue:`11295`)
 - Bug in comparisons of Series vs list-likes (:issue:`11339`)
-- Bug in ``DataFrame.replace`` with a ``datetime64[ns, tz]`` and a non-compat to_replace (:issue:`11326`)
+
+
+- Bug in ``DataFrame.replace`` with a ``datetime64[ns, tz]`` and a non-compat to_replace (:issue:`11326`, :issue:`11153`)
+
 
 
 - Bug in list-like indexing with a mixed-integer Index (:issue:`11320`)

pandas/core/generic.py

@@ -2999,8 +2999,6 @@ def replace(self, to_replace=None, value=None, inplace=False, limit=None,
                            '{0!r}').format(type(to_replace).__name__)
                     raise TypeError(msg)  # pragma: no cover
 
-        new_data = new_data.convert(copy=not inplace, numeric=False)
-
         if inplace:
             self._update_inplace(new_data)
         else: