From cold winter mornings to below-freezing nights, a properly installed furnace keeps your home safe, warm, and efficient.
At BPM Heating, Cooling & Plumbing, we specialize in high-efficiency gas, electric, and oil furnaces built for performance and durability. Whether you’re researching heating options or want to understand how your current furnace works, this guide covers everything you need to know.
What Is a Furnace and How Does It Work?
A furnace is a forced-air heating system that generates heat and distributes it through ductwork to every room in your home. Here’s how it works:
- Heat generation: A gas burner, electric coil, or oil-fired chamber creates heat inside a heat exchanger.
- Air circulation: A blower motor pulls cool air from return ducts, warms it as it passes over the heat exchanger, and pushes it through supply ducts.
- Exhaust: Combustion gases are safely vented outside via a flue or PVC exhaust pipe.
- Control: A thermostat regulates when the system cycles on and off to maintain your desired indoor temperature.
Modern furnaces are paired with advanced controls and safety systems to maximize comfort and efficiency while minimizing fuel use.
Types of Furnaces
Not all furnaces operate the same way. Here are the most common types:
- Gas Furnaces – Powered by natural gas or propane. They use burners and ignition systems to heat air. Known for quick response, lower fuel costs, and high AFUE ratings (up to 98%).
- Electric Furnaces – Use electric resistance coils to generate heat. Require no flue or combustion ventilation. Great for homes without gas access.
- Oil Furnaces – Less common, but still used in older homes. Oil is atomized and ignited in a combustion chamber, producing strong radiant heat.
- Single-Stage vs. Two-Stage vs. Modulating – Refers to how the furnace adjusts heat output. Two-stage and modulating furnaces provide better comfort, quieter operation, and energy savings by running at lower levels most of the time.
- Variable-Speed Blowers – Blowers with ECM motors adjust airflow based on demand, enhancing comfort and reducing noise compared to single-speed blowers.
Furnace Efficiency Explained
Furnace efficiency is measured by AFUE (Annual Fuel Utilization Efficiency), which indicates how much fuel is converted into usable heat:
- 80% AFUE = 80% of fuel becomes heat, 20% is lost
- 95%+ AFUE = High-efficiency system with sealed combustion and secondary heat exchanger
Other energy-saving technologies include:
- ECM blower motors – Use less electricity and offer variable-speed comfort
- Sealed combustion – Pulls outside air for combustion instead of indoor air
- Smart thermostats – Optimize temperature control and lower energy waste
Common Furnace Components
Understanding key parts can help you troubleshoot or maintain your furnace:
- Heat Exchanger – Transfers heat from combustion chamber to circulating air
- Burner or Heating Coil – Ignites fuel or generates electric heat
- Blower Motor – Moves air through ductwork
- Flame Sensor / Igniter – Ensures safe ignition and operation
- Control Board – Coordinates furnace operations
- Thermostat – Signals the system when to turn on/off
- Flue Pipe – Vents combustion gases safely outdoors
Furnace Installation, Repair & Maintenance
We install, replace, service, and maintain all types of furnaces. Explore our dedicated pages to learn more:
- Learn more about our furnace installation and replacement.
- Learn more about our furnace repair services.
Brands We Service
We install and service all major furnace brands, including:
- Lennox (Premier Dealer)
- Trane
- Goodman
- Carrier
- Rheem
- Bryant
- York
- American Standard
Our technicians are trained to diagnose, repair, and install all types of gas, electric, and oil furnaces—even if we didn’t install it.
Our Service Area
At BPM Heating, Cooling & Plumbing, we proudly serve homeowners across Frederick County and Washington County, Maryland. Whether you’re replacing an old oil furnace or installing high-efficiency gas heat, our team delivers fast, expert service you can count on.
| Frederick County, MD | Washington County, MD |
|---|---|
| Brunswick | Boonsboro |
| Emmitsburg | Clear Spring |
| Frederick | Funkstown |
| Mt. Airy | Hagerstown |
| Myersville | Hancock |
| New Market | Keedysville |
| Thurmont | Sharpsburg |
| Walkersville | Smithsburg |
| Woodsboro | Williamsport |
Get Expert Help With Your Furnace
Whether you’re learning about furnace technology or ready to replace your outdated system, BPM Heating, Cooling & Plumbing is here to help. We offer honest recommendations, fast scheduling, and expert workmanship you can trust.
Call (240) 200-0887 or schedule a consultation online today.
