503.15 Obstructions.
FGC § 503.15
Devices that retard the flow of vent gases shall not be installed in a vent connector, chimney or vent. The following shall not be considered as obstructions: 1. Draft regulators and safety controls specifically listed for installation in venting systems and installed in accordance with the terms of their listing and manufacturer's instructions.
2.Approved draft regulators and safety controls that are designed and installed in accordance with approved engineering methods.
3.Listed heat reclaimers and automatically operated vent dampers installed in accordance with the terms of their listing and manufacturer's instruction.
4.Approved economizers, heat reclaimers and recuperators installed in venting systems of appliances not required to be equipped with draft hoods, provided that the appliance manufacturer's instructions cover the installation of such a device in the venting system and performance in accordance with Sections 503.3 and 503.3.1 is obtained.
5.Vent dampers serving listed appliances installed in accordance with Sections 504.2.1 and 504.3.1 or other approved engineering methods.
