What Are Sealed Combustion Appliances? Benefits for Efficiency and Safety

Posted December 20, 2016

Appliances like furnaces, water heaters, and clothes dryers that run on natural gas rely on combustion to generate heat. Traditional appliances use atmospheric combustion, drawing air from inside the home to burn fuel and expelling the exhaust gases through a flue or chimney. 

In contrast, sealed combustion appliances are designed to draw air from outside the home and vent exhaust gases back outdoors, improving both efficiency and safety.

How Do Sealed Combustion Appliances Work?

Sealed combustion appliances use a tightly enclosed chamber for the combustion process. Instead of relying on indoor air, they are connected to the outdoors via two separate pipes:

  • Supply Pipe: Draws fresh outdoor air into the appliance for combustion.
  • Exhaust Pipe: Vents the byproducts of combustion, including carbon monoxide (CO), safely back outside.

This system ensures that the combustion process is completely isolated from the home’s interior, improving both energy efficiency and indoor air quality.

The Advantages of Sealed Combustion Appliances

Sealed combustion technology offers several benefits that make it an excellent choice for modern homes:

1. Higher Energy Efficiency

Sealed combustion appliances achieve higher Annual Fuel Utilization Efficiency (AFUE) ratings, often 90% or higher, because they eliminate the need to use conditioned indoor air for combustion. By drawing air from outside, these appliances reduce heat loss and maximize energy use, saving money on utility bills.

2. Improved Safety

Traditional combustion appliances with exposed flames can pose risks such as:

  • Fires caused by flammable materials near the appliance.
  • Carbon monoxide (CO) leaks due to backdrafting of exhaust gases into the home.

Sealed combustion eliminates these risks by enclosing the combustion process and directly venting exhaust gases outdoors, keeping your home safer.

3. Better Indoor Air Quality

By isolating the combustion process, sealed combustion appliances prevent contaminants like carbon monoxide and other harmful gases from entering your home. This is particularly beneficial for households with allergy sufferers or respiratory conditions.

4. No Negative Pressure Issues

Traditional appliances can create negative pressure inside the home, pulling in unconditioned air through leaks or openings. Sealed combustion appliances avoid this problem by using outdoor air, helping to maintain a consistent and comfortable indoor environment.

Are Sealed Combustion Appliances Right for Your Home?

Sealed combustion appliances are ideal for energy-efficient homes, especially those with modern insulation and air-sealing techniques. They are particularly beneficial for:

  • Homes with tight construction, where indoor air exchange is limited.
  • Homeowners looking to reduce energy consumption and utility costs.
  • Families concerned about indoor air quality and safety.

Maintenance Tips for Sealed Combustion Appliances

To keep your sealed combustion appliances operating safely and efficiently, follow these maintenance tips:

  • Schedule annual inspections by a qualified technician to check the combustion chamber, supply, and exhaust pipes.
  • Replace air filters regularly if your appliance uses them to maintain proper airflow.
  • Ensure that the outdoor vents are free of obstructions like snow, debris, or bird nests.
  • Install a carbon monoxide detector near sleeping areas for added safety.

Have Questions About Sealed Combustion Appliances?

At ABC Plumbing, Sewer, Heating, Cooling, and Electric, we specialize in high-efficiency appliances, including sealed combustion furnaces and water heaters. If you’re considering upgrading your home’s heating or have questions about sealed combustion technology, our team is here to help.

Scroll further down this page, locate the location closest to you, and click the phone number to call us. Let us help you improve your home’s efficiency, safety, and comfort with sealed combustion appliances.

ABC Plumbing Locations

Arlington Heights, IL

220 W Campus Dr
Arlington Heights, IL 60004
Phone: (888) 991-3942

Evanston, IL

828 Davis St UNIT 205
Evanston, IL 60201
Phone: (888) 868-9369

Downers Grove, IL

1001 Ogden Ave LL4
Downers Grove, IL 60515
Phone: (888) 412-3566

Tampa, FL

4326 W El Prado Blvd Suite 7
Tampa, FL 33629
Phone: (888) 594-9030

Largo, FL

11701 S Belcher Rd Suite 127
Largo, FL 33773
Phone: (888) 465-9799


Our Promises To You

  • Icon of a clock with the number 24

    Convenient For You

    We Work on Your Schedule

  • Icon of a ribbon with a checkmark in the middle

    Background Checks

    We do Drug Tests And
Background Checks Before Hiring

  • Icon of two hands shaking

    No Need For Stress

    Get ABCs Worry-Free Guarantee at No Cost

  • Icon of a shield with a hand giving a thumbs up

    No Surprises

    Pricing is By the Job, Not the Hour