Chimnet Venting

I know with chimney venting the smaller item (water heater) enters the chimney above the larger item (heating unit). I need the proper paragraph for a report to support this.

1 Like

When connecting more than one gas/oil appliance to a common chimney, it is required to vent the smaller btu unit above the larger btu unit for proper draft and fan operation as well as having the proper sized chimney/vent.

Thank you guys.