As ABC News is replayed multiple times throughout each day on the ABC News channel on channel 24 you may want to only record the ABC showing at 7pm on channel 2 or 21 instead of many times each day on the ABC News 24 channel.
To do this when setting up the series recording from the IceTV website or IceTV phone app you select the Advanced option of "Only standard def.". This will ignore any of the showings on ABC News 24 (as channel 24 is broadcast in HD) and will only record ABC News on the main ABC channel (on 2 or 21).
If you have already setup the series recording you can edit its options by clicking on TV Guide at the top right of the IceTV website, then clicking on My Series. In My Series look for the listing for ABC News and click on it to see the options for that series recording. Now click on Advanced Options and you will see that the Quality setting is probably set to the default 'Prefer high def.' which you can now change to 'Only standard def.' Finally, click on Update Series Recording and the IceTV system will remove any showings that no longer match your updated settings (i.e. It will remove all showings that are on the HD 'ABC News 24' channel).
If you prefer to record the news in HD you can leave the series Quality setting set to 'Prefer high def.' and instead set the 'This Time' option to 7:00 pm which will then record the ABC News on channel 24 but only for showings that the guide has listed to start at 7pm.