Boiler vs. Furnace

What’s the Difference, Why It Matters

Your heating oil system can either be a furnace or a boiler. Both of these heating units will keep you warm, but there is some information you should know that may come in handy if a problem arises.

If it’s something minor, you may be able to correct it yourself. And if you need to discuss something with a heating oil service technician, you will at least have a working knowledge of how your heating system operates.

How an Oil Furnace Works

Because it generates heated air, a furnace is also known as a forced-air or warm-air system. Here is how it produces heat.

the thermostat sends a signal to the controls on the oil burner.
the fuel pump then draws oil through a filter to the burner.
the burner turns the oil into a fine spray, mixes it with air, and ignites it in the combustion chamber, causing the chamber to become very hot.
air absorbs heat in the heat exchanger.
a blower sends this air through ducts and exits through vents to heat the home.
the air eventually circulates back to the heat exchanger and the cycle continues.
combustion emissions are vented out the flue.

How a Boiler Works

Boilers use hot water or steam to heat your home. Another name for a boiler is a hydronic heating system, which is defined as a system that transfers heat via a circulating fluid, such as water, in a closed system of pipes.

Steam boilers can still be found in older homes, usually ones built before the 1950s. If you have this type of system, your boiler stays true to its name because it actually has to boil water to make steam before your heat can be distributed.

In comparison, newer boilers do not need to boil the water to make steam. Instead, they use hot water to distribute heat through a home’s piping. The heat is distributed through your home by either radiators or baseboards.

Because a boiler is a closed-loop system, water does not need to be constantly brought in or replaced, making it more efficient.

Some of the key components of a boiler system include:

A burner, where the heating oil is ignited in the combustion chamber.
A heat exchanger, which allows heat to be exchanged between two substances (fuel oil and water) while not allowing the two substances to mix together.
Circulator pumps, which push the hot water from the boiler into the piping. A steam boiler doesn’t require a circulator pump because it doesn’t need to be pushed into the piping. It rises up the pipes naturally.
Piping, which includes supply lines to deliver the heated water (or steam) to the radiators or baseboards. When the water cools or the steam turns back into the water, return lines bring the water back to the boiler for re-heating.

Tip for Your Oil Furnace: Check the Air Filter

All warm air systems have air filters to screen out dust and other impurities. In general, you should check the filter’s condition about once a month during the heating season and change/clean it when necessary. Contact your heating oil service company if you’re not familiar with this procedure.

Tips for Your Oil Boiler

If you’re not getting heat from a baseboard, check to see if the damper is open. Make sure the bottom of the unit isn’t blocked by heavy carpeting.
A radiator valve has only two positions, on and off. Keeping the valve’s handle in between does not regulate the temperature but can strain the pipes and produce a hammering sound.
For steam systems, check the boiler’s water gauge periodically. Low water levels are a leading cause of shutdowns. Steam boilers should also be “flushed” when the water in the gauge looks rusty. Ask your heating oil service contractor if you’re not familiar with this procedure.

General Heating System Tips

Keep the area around your system as clean and clutter-free as possible. Never store anything flammable near your system.
Keep registers, baseboards, or radiators clean and unobstructed to ensure maximum airflow.

New Boiler Installation or New Furnace Installation

If you think it’s time to replace your old furnace or boiler, please contact your heating oil service company about your options in a boiler installation or furnace installation. Today’s oil boilers and oil furnaces offer homeowners a great opportunity to increase their comfort while decreasing their energy usage.

New systems now heat your home using significantly less energy compared to older generation equipment. Energy-efficient equipment can be installed with controls to use only as much fuel as needed to heat your home or a specific part of your home.