What’s the Purpose of a Fresh Air Intake?

Your HVAC system, in addition to maintaining comfortable temperatures and controlling humidity, plays an important role in air quality. A fresh air intake allows the system to bring fresh air in from outside and deliver it to rooms via specialized vents. Your home is legally required to have a fresh air intake if a gas appliance such as a furnace is installed.

To comply with modern building codes, newer homes may have air intakes in several locations. Their main purposes include:

• Preventing Carbon Monoxide Buildup: Without an intake or if one is blocked, negative pressure can cause carbon monoxide to back up in the flue vent and build up in your home. This colorless, odorless gas is deadly in high concentrations.
• Delivering Oxygen for Combustion: For every foot of gas a furnace uses, it needs about thirty feet of air. A fresh air intake delivers more oxygen from outside rather than the unit burning up more oxygen from your indoor air.
• Improving Indoor Air Quality: A conventional furnace pulls air from your house. The fresh air intake delivers replacement air to draw from. Otherwise, the furnace will draw air from dryer vents, attics, crawlspaces, and other unconditioned areas, reducing air quality.
• Improving Efficiency: Without a flow of fresh air, a furnace in a restricted space won’t run as efficiently. Its blower motor will run slower. Some fan motors will use more electricity to compensate, possibly increasing your energy bill.
• Extending Furnace Life: Air contaminated with corrosive materials can cause corrosion in heat exchangers, burners, and other components, shortening the life of your furnace.

How Does a Fresh Air Intake Work?

Often used for gas heaters, gas dryers, and fireplaces, it functions as a passageway to allow air into your home from outside. The air intake vent contains a filter to clean incoming air. It’s important to clean or replace the filter periodically and check the intake for debris or pests to clean out.

Don’t Block Your Fresh Air Intake

Some homeowners block or stuff their fresh air intake believing it will affect heating. This can have negative consequences, including a backdraft of carbon monoxide and toxic fumes. Even high-efficiency furnaces require fresh air, so the intake should remain in place (or one installed) if you’re replacing your unit with a newer system.

What Does It Look Like?

It typically looks like a grilled vent. You’ll find it in the same room as your gas appliance. If not on a wall, it might be located behind the appliance or inside a door. Some vents run up to the attic and then outside, while others lead directly outside. Fresh air intake vents are not make-up air systems that focus solely on delivering enough air to gas appliances.

Looking for Heating and Air Quality Services? Black Hills Can Help

Whether you need furnace repair or believe there’s an indoor air quality problem, the licensed technicians at Black Hills Home Services can help. We take various measures to extend the lifespan of your heater and maximize its efficiency. Aside from repairs and maintenance, we can provide or service a fresh air intake, so your heating system works at full capacity and your family is safe. To learn more or request furnace or air quality services, contact us online or call 888-704-6293.