Can someone give advice on installing an effluent pump in my cellar. It is an add-on cellar and the floor sits about 4' below the main sewer line. I'm guessing i shouldn't tie directly into the main line since if the check valve fails, and my sewer backs up, it would flood my cellar. I'm thinking I should tie into something like a 1 1/2" or 2" sink line from an upstairs sink. Is that correct? And if so, do I need to provide some kind of vent in the assembly or just sweep right into that sink line? Any help would be greatly appreciated!