Can I remove the broken air conditioning unit from my havc unit and still use the furnace

Yes most definitely you do NOT have to have both with a split system... If you are not going to replace the ac unit at this time.. u need to disconnect the call wires to the outside unit ( if its turned on intact it may short your t-stat. the coil under your unit can stay also but your effic. Will go up if you pull it. NO matter what have refrigerant pro. Removed and disposed of and lineset Completely SEALED ( in case you ever want to re install )