18-28-1205.1.1 Heat exchangers.
   Shutoff valves shall be installed on the supply and return side of a heat exchanger.
   Exception: Shut off valves shall not be required when heat exchangers are integral with a boiler; or are a component of a manufacturer's boiler and heat exchanger packaged unit, and are capable of being isolated from the hydronic system by the supply and return valves required by Section 18-28-1005.1.