Gas furnaces do use air filters to maintain air quality and enhance the efficiency of the HVAC system. The primary role of gas furnace filters is to protect the blower fan, maintain air quality, and enhance the HVAC system’s efficiency.
What Types of Air Filters Are Used in Gas Furnaces?
There are several types of air filters commonly used in gas furnaces:
- Fiberglass/Synthetic Filters
- Polyester Filters
- Electrostatic Filters
- Pleated Filters
- HEPA Filters
Fiberglass/Synthetic Filters
These are inexpensive and disposable. They can catch up to 80% of particles 50 microns or larger and 25% of particles between 3 to 10 microns. They are effective in preventing dust and dirt from building up on furnace components but do not filter out harmful contaminants.
Polyester Filters
Made from high-quality materials, these filters trap 80% to 95% of particles 5 microns or larger. They are more expensive than fiberglass filters but offer better protection against pollutants.
Electrostatic Filters
These filters use self-charging fibers to attract particles. They can be disposable or washable, with MERV ratings ranging from 4 to 10. Washable versions last longer but require proper maintenance to avoid mold and mildew.
Pleated Filters
Designed with pleats to increase the surface area, these filters trap particulates as small as 0.3 microns. They are more efficient and last longer than fiberglass filters but may require more frequent replacements as the MERV rating increases.
HEPA Filters
High-efficiency particulate air filters capture up to 99% of particles 0.3 microns or larger. However, they can reduce airflow and increase energy costs.
How to Choose the Best Filter for Your Gas Furnace?
When choosing a filter for your gas furnace, consider the following factors:
MERV Ratings
For residential homes, a MERV rating between 8 and 12 is usually sufficient. Higher ratings may overextend or block airflow, causing service issues.
Filter Material
- Fiberglass/Synthetic: Basic protection, low cost, but less effective against smaller particles.
- Polyester: Better protection, higher cost.
- Electrostatic: Effective for small particles, can be washable.
- Pleated: High efficiency, longer-lasting.
- HEPA: High-end filtration, but may reduce airflow.
Size Specifications
Ensure the filter size matches your system’s requirements. Filter sizes typically range from 10 to 30 inches in height and length, with thicknesses between 1 and 5 inches.
How to Maintain and Replace Gas Furnace Filters?
- Check the Filter Regularly: Inspect the filter every 30 to 90 days, depending on usage and indoor air quality.
- Replace or Clean the Filter: Replace disposable filters or clean washable filters according to the manufacturer’s instructions. For washable filters, wash with soap and water, and let them dry completely before reinstalling.
- Consider Seasonal Changes: Change filters more frequently during peak usage seasons (e.g., winter and summer) or if you notice a decrease in airflow.
What Are the Typical Costs and Measurements of Gas Furnace Filters?
- Costs: Disposable filters can range from a few dollars to over $20, depending on the type and quality. Washable filters, while more expensive upfront, can last up to 10 years.
- Measurements: Common filter sizes include 10×20 inches, 12×24 inches, and 16×25 inches, with thicknesses of 1, 2, 4, or 5 inches.
References:
1. HVAC.com: “What Are the Different Types of Furnace Filters?”
2. Filterbuy: “Types of Furnace Filters You Can Buy For Your Home”
3. Ushomefilter: “A Complete Guide To Different Types of Furnace Filters”
