For this job, Trevor & Anthony came to look at the venting for the Tankless Water Heater. After opening up the unit we found that the unit had concentric venting and deemed it correct for the venting it currently had. Although, the vent could have been ran in a cleaner manner the current set up works and isn’t causing any issues with how it is. I sent the customer an estimate to add a mini tankless unit underneath the kitchen sink in order to have hot water quicker and in higher volume.