I had a chimney company run a new stainless steel liner down my chimney and this is how they connected the furnace and water heater to connect to the liner in the chimney. At the time, I suspected there may be something wrong with this setup but not being an expert, did not question. Further research, on sites such as this, made me suspect potential problems. Previously, the water heater and furnace had 2 separate vent pipes running to a clay lined chimney with the water heater vent pipe above the furnace vent pipe. I believe this was a good venting situation. Now, there is only one connection into the stainless steel chimney liner and the picture posted is how the chimney lining company solved the venting of 2 units (furnace and water heater) into 1 liner opening. I have no intention of going back to the chimney liner company for a solution to this issue. I suppose my path forward is to call my HVAC company and have them examine and correct the issue. Do you have ideas as to how I will be able to successfully vent both water heater and furnace into one chimney liner opening? Any help would be appreciated. I just want to be able to speak intelligently with whomever I hire to resolve this issue. Thanks.