Beautiful, Philadelphia, the City of Brotherly Love!
The proper way to install a water heater is shown below in pictures.
I had a little go around with the installer on the phone, he swore up and down the water heater was one installed to code and two he could get half a dozen master plumbers and hvac guys he knows to vouch for his installation. In fact he has been in the business for 5 years and all of his water tanks were installed this way.
I handed the installation instructions and the phone to the HO and had him read the part about how this water heater cannot be vented into a common flue. Also having him read the warning about using only pvc for venting material.
Fernco fittings were definitely not mentioned as alternatives to pvc, neither was the glue-less pvc fittings.
I was called out because gas boiler was completely carbonized to the point the roll and blocked vent switch were burnt to a crisp.
The boiler is another wall of shame worthy install, nice how the installer decided to install it just behind a pole. The HO told me the original water tank was on the right side of the boiler hence the unsupported gas line horizontally across the front of the boiler, and the turned up 3 inch sheet metal flue. Said the pole was there first, hard to believe but then if you I had taken pictures of the high velocity blower coil 5 feet father down from the boiler you would understand what a cluster F of a job the entire house renovation was. One of the high velocity vents is in the middle of the hallway adjacent to the thermostat, which is installed on an outside wall.
Next time I get out there I will post up the pictures of the high velocity system for a good laugh.
You don't get paid for the hour. You get paid for the value you bring to the hour. Jim Rohn