How your oil-fired heating system works









Oil-fired heating systems distribute heat in one of three ways: warm air through vents, hot water through baseboards, or steam through radiators.

Your thermostat senses that the room temperature has fallen below your thermostat setting and sends a signal to your heating system to provide heat for your home.

When your oil burner is engaged, heating oil travels from the tank to the burner by way of a pump where it becomes a fine mist mixed with air. The fuel/air mixture is then injected into the burner where it is ignited in the combustion chamber.

Heating system types
Depending on the type of system you have, water-based or warm air, the system works differently to disperse heat throughout your home.

There are two main types of water-based systems: hot water systems and steam systems. Water is heated in either a cast iron or steel boiler before it is dispersed throughout your home.

In a hot water system, the heated water is circulated through radiators or baseboards.

In a steam system, the water turns to steam and rises through pipes to the radiators. In a warm air system, your furnace heats air. A blower then sends the heated air up through the ducts and out of vents in your floors or walls. The air gets drawn back to the furnace through a return duct and the cycle repeats.

Finally, the emissions from the combustion of fuel and air exit the system through a flue pipe that runs out of your home through the chimney.


Related articles


Click on the links below to find additional insights and information:

Oil heat - what you need to know ›

What is oil ›

The facts about oil vs. gas heating ›

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