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Sealed/Vented New Gas Appliances

Any new gas appliances are sealed-combustion / vented to the outdoors — or the project goes all-electric.

Spec

Any new gas appliances are sealed-combustion / vented to the outdoors — or the project goes all-electric.

Applies uniformly from Silver upward.

Scope

All NEW gas appliances installed in the dwelling — furnace, boiler, water heater, dryer, fireplace.

Requirements

  1. 01.

    New gas appliances must be sealed-combustion (direct-vent) — drawing combustion air from outside and exhausting to outside through dedicated venting.

  2. 02.

    Atmospherically vented or naturally drafted gas appliances are not permitted for new installations at Silver and above.

  3. 03.

    OR the project may convert to all-electric appliances (which automatically satisfies the requirement plus aligns with Gold all-electric goals).

Documentation

Evidence the inspector / Institute will need.

  1. 01.

    Equipment spec sheets for all new gas appliances showing sealed-combustion / direct-vent design.

  2. 02.

    Photos of installed combustion-air intake and exhaust terminations.

Guidance

Why sealed-combustion is now baseline

Atmospheric-draft appliances are dependent on neutral house pressure to vent properly — they backdraft in any home with strong exhaust fans (kitchen hood, bath fans, dryer) or wind effects. Sealed-combustion appliances are immune to backdrafting because the entire combustion air/exhaust path is isolated from house air.

Note

Most furnaces sold in the U.S. today are already sealed-combustion (95%+ AFUE condensing units). Atmospheric-draft is most commonly found in older tank water heaters — replacement with a sealed-combustion or electric HPWH is the easiest path.