How Does A Furnace Work?

The most popular kind of furnace is a gas-powered central air system, which warms the air in one location before distributing it through ducts and vents throughout the house. This system is often referred to as a forced warm-air distribution system or ducted warm-air system.

The gas valve, burners, heat exchanger, blower, duct, ventilation system, control system (thermostat and electrical controls), and other minor components make up your furnace. Combustion gasses from your furnace are vented outside your house through a flue pipe when it generates heat.

Understanding the Heating Cycle

  • The furnace is connected to the gas supply through a pipe that enters your house from the outside.
  • The burner ignites the gas once it reaches your furnace from a storage tank (LPG) or the local gas supply network (natural gas).
  • Your home’s cold air enters the furnace, where the heat exchanger’s heat-trapping gas warms it as it burns.
  • The furnace’s vent is used to pump combustion exhaust outside of the house through an exhaust pipe.
  • The blower fan distributes the warm air around the home according to where the thermostats sense a demand for heat.
  • As the warm air is dispersed, the temperature of the inside air progressively rises. Return ducts are used to send cold air back to the furnace.
  • The thermostat shuts off the gas valve when it detects the desired temperature has been attained. 

To affirm the smooth functioning of the above process, get in touch with a professional for heating repair in Marysville.

Furnace Parts & Systems

Blower Motor

Warm air from the furnace is distributed throughout your house through ductwork. It is important that this blower fan also moves air for cooling. This is among the many reasons why having a suitable heating and cooling system is essential.

Heat Exchanger

A group of heat-retaining metal tubes are connected to the furnace’s heat source. When air is circulated through the heat exchanger and into ducting, the air inside your home is warmed.

Combustion Chamber

This is where the heat exchanger’s magic happens. It is the space that is exposed to air movement. Among the numerous regions cleaned during normal maintenance, this area must be maintained precisely and kept unaltered.


This filter is still an essential component of both the furnace and the air conditioner. After being cycled around your home, the air returning to the furnace is filtered. Your HVAC system might become clogged by a poor or filthy filter. Keeping dirt and dust out of your furnace’s components is crucial for long-term safety and effectiveness.

Furnace Maintenance and Safety!

Gas furnaces need certain routine maintenance and safety measures, much like any combustion-based home heating equipment.

  • Keeping a safe distance between anything that can catch fire and the furnace.
  • Regularly replacing the air filter. At least every three months in case of frequent usage.
  • Installing at least one carbon monoxide (CO) detector in your house. Check it frequently.
  • Avoid closing too many furnace registers at once, and keep them clean and free of blockage. To prevent excessive heat accumulation in the furnace, keep at least two-thirds of them open at all times.
  • A qualified technician, like a heating contractor in Lynnwood, WA, will assist you with regular cleaning and maintenance appointments.


For all of your needs regarding heating replacement, contact 1st Response HVAC. You can rely on our experienced and qualified professionals in Lynnwood furnace repair service to evaluate your furnace and the HVAC system anytime, identify impending issues, and resolve them.