This is my second post here. I am installing (with a Licensed plumber) a Paloma Phh-32 Nat gas Tankless heater to replace my nat gas storage heater. I am going to utilize the existing chase and roof penetration to run my new 3 Inch PVC vent and exhaust lines to a single vent thru the roof. I wanted to post a diagram I drew showing some of the installation primarily the vent design and condensation drains. The heater itself is going to mounted high up in a closet so condensation will easily drain by gravity to my laundry sink. I wanted to get your input on the vent design and plan. Thanks!!