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I need to relocate some vent terminals on the exterior wall. Is there a clearance requirement between the dryer exhaust vent and the combustion air intake for the furnace? The dryer is electric. The furnace is single pipe (not direct vent). The combustion air intake is a 4" duct bringing outside air close to the furnace.

QuoteClause 7.5.2 - A moisture-exhaust duct shall not terminate within 3 ft (1m) in any direction of any pressure regulator vent termination or fresh-air intake.

Most inspectors won't enforce this unless the dryer is on gas, however I believe Clause 7.5.2 applies to an electric dryer as well.

The following is from the B149.1-10 gas code,

QuoteClause 8.3.7 - An air-supply opening shall not be located within 3 ft (1 m) of a moisture exhaust duct.
Note: A moisture-exhaust duct (e.g., a gas or electric clothes dryer discharge; spa exhaust) is considered to interfere with the combustion air intake when located within 3 ft (1 m) of the air intake.

Now inspectors won't allow the installation of any residential dryer vent within 3' of an intake opening.