Cast iron radiators are common in older Toronto homes and apartments. They accumulate dust in the fins and sections, which burns off at the start of each heating season and creates the distinctive smell of a radiator first turning on. Regular cleaning prevents this and keeps the radiator heating efficiently — dust acts as an insulator on the fins.
Vacuuming (Before Heating Season)
- Turn off the radiator or allow it to cool completely before cleaning — a hot radiator is uncomfortable and potentially dangerous to work near
- Use a vacuum with a narrow crevice attachment or a radiator brush (a long, thin flexible brush sold at hardware stores) to clean between the fins and sections
- Work from top to bottom — dislodged dust falls down
- Use a handheld vacuum or a dust sheet on the floor to catch falling debris
- For radiators with many fine sections, blow compressed air between the fins first to dislodge dust, then vacuum
Wiping the Exterior
- Wipe the exterior surfaces with a damp cloth — dish soap and warm water for grimy radiators
- Dry thoroughly immediately — leaving moisture on bare or flaking paint-covered iron promotes rust
- Use an old toothbrush for the grooves and ornamental details on decorative cast iron radiators
Flaking Paint
- Flaking paint on a radiator is a common issue in older homes and can contain lead paint in pre-1978 housing — if you suspect lead paint, do not sand or scrape without appropriate precautions
- Loose flakes can be gently removed with a soft brush; repainting with a heat-resistant radiator paint (rated to 200°C) prevents further flaking and rust
- Standard latex paint over a hot radiator blisters and peels — always use radiator-specific paint
Frequency
- Vacuum radiators thoroughly at the end of summer before turning the heat on for the first time each fall
- Quick wipe-down monthly during heating season