Enable and disable the AutoDelete options from the AutoDelete menu in the Console. If an option is checked, then it's enabled (ON). Click the menu item to toggle the value (ON/OFF).

If this option is Enabled, duplicate episode recordings will be deleted automatically immediately after they are recorded.
This option is only applied in the following cases:
A duplicate episode is a recording with the same series name, episode title and original-air-date.
Important: Sometimes, Media Center recordings do not have the episode title and/or original-air-date properly encoded in the metadata associated with the recording. This is often the case with news programs and soaps, among others. In this case, the episodes all look like duplicates and will be deleted if this AutoDelete option is Enabled. Also, see WTV File Support.
If this option is Enabled, new recordings of checked episodes will be deleted immediately after they are recorded.
Checked episodes are stored in the SeriesInfo database and are retained, even after the recording has been deleted.