I have a Rheem water heater with a power vent and am having difficulty venting the unit properly. The 2″ opening has an adapter to 3″ pipe immediately above the power vent than rises approx. 2 feet to a 90 deg. elbow than aprox. 3 ft later has a 90 and a 45 to run between the floor joists and a straight shot of 30 feet to the rear of my house. I know it’s in the venting setup. Also can basement floor drains be plugged and sealed permanently because during heavy rains we can get alot of drain water backing up thru them. Thanks for your help.