HomeAnswersBoiler or furnace? How to tell what you have
Boiler or furnace? How to tell what you have
The thirty-second test
Look for what carries the heat: if pipes with radiators or baseboards, it is a boiler and it heats water. If wide sheet-metal ducts with floor vents, it is a furnace and it heats air. That single difference decides which trade you need.
Boilers
No blower, no ductwork, and a pressure gauge or a sight glass on the unit. Older Green Bay houses often have cast-iron radiators with a boiler. Boilers get serviced on a different schedule and by technicians who work on hydronics.
Furnaces
A blower compartment, a filter slot, and ducts. Most houses built after the mid-twentieth century have one. Filter changes and airflow problems are furnace concerns; boilers do not have filters.
Why it matters when you request a visit
Telling the desk which one you have puts the request in front of the right trade. A boiler request sent to an air-side company wastes a day.
Still not sure
Photograph the unit and the label, and mention what heats the room: radiators, baseboards, or floor vents. That is enough to route it correctly.