What does the Heating indicator symbol look like?

Three wavy vertical lines rising above a thick horizontal bar. It is also called “heat on”, “heating”, “heating element on” and “working indicator”.

Which products show the Heating indicator symbol?

It is recorded on De'Longhi TRRS series digital oil-filled radiator (TRRS).

Heating indicator symbol: three wavy vertical lines rising above a thick horizontal bar

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Heating & air conditioning

Heating indicator

Three wavy vertical lines rising above a thick horizontal bar. · also called “heat on”, “heating”, “heating element on”, “working indicator”

What it means on de'longhi

Working (heating) indicator

Shows whether the radiator is heating, by colour: red at maximum power, orange at medium, green at minimum. When the icon is absent the radiator is not heating at that moment.

Source · Manufacturer manual De'Longhi TRRS series oil-filled radiator instructions · checked Nov 11, 2026

Where it appears

Heating & air conditioning

De'Longhi TRRS series digital oil-filled radiator
TRRSThis meaningChart

Questions about the Heating indicator symbol

What does the Heating indicator symbol mean on the De'Longhi TRRS series digital oil-filled radiator (TRRS)?: Shows whether the radiator is heating, by colour: red at maximum power, orange at medium, green at minimum. When the icon is absent the radiator is not heating at that moment.
What does the Heating indicator symbol look like?: Three wavy vertical lines rising above a thick horizontal bar. It is also called “heat on”, “heating”, “heating element on” and “working indicator”.
Which products show the Heating indicator symbol?: It is recorded on De'Longhi TRRS series digital oil-filled radiator (TRRS).

Checked against the source · Nov 11, 2026 · How we verify

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