Given: An unlisted, residential gas furnace with a draft hood has a flue temperature at that draft hood of more than 500 F. The chimney connector is a single-wall metal pipe. What minimum clearance is required between the connector and any unprotected combustible material?

Given: An unlisted, residential gas furnace with a draft hood has a flue temperature at that draft hood of more than 500 F. The chimney connector is a single-wall metal pipe. What minimum clearance is required between the connector and any unprotected combustible material?