Heating control
Identifies the heating system's control — the one that sends warmed air into the cabin.
What pressing it does
It marks the control for the heater. How much heat you get depends on the engine: SEAT's Ateca manual says the heating works best, and the full heat output needed to clear the windows quickly is only available, once the engine has reached its normal temperature.
Check your car's manual: makes and models differ in what a button does, which positions a switch has and whether it works with the engine off, and your owner's manual is the authority for your car.
- What it looks like
- Three wavy arrows rising from a line, with no frame around them
- Also labelled
- Heater; Heat
- Standard
- UN R121 and FMVSS 101
What to check in your car's manual
Which knob or button carries this symbol on your car (on many panels temperature is a dial instead), and whether your car has an auxiliary heater that can run with the engine off.
Where makes differ
The same three wavy arrows mean different things depending on what surrounds them: alone they are the heater; inside a windscreen outline they are the windscreen demister; inside a rectangle, the rear-window demister; above a seat or steering wheel, a heated seat or wheel. SEAT's Ateca can also have a fuel-burning auxiliary heater with its own button.
Where the regulations list it
| Rule | Row | Function | Must be lit with the headlamps |
|---|---|---|---|
| UN R121 | Table, item 38 “Heating system” | Control | Yes |
| FMVSS 101 | Table 1, “Heating and Air conditioning system”: no symbol or word set | Control | Yes |
UN Regulation No. 121 (01 series), location and identification of hand controls, tell-tales and indicators: Cars (M) and light goods vehicles (N1) approved under the UN 1958 Agreement, which includes the EU, UK and Japan. Paragraph 5.2.1: where fitted, a control listed in the table is identified by the symbol in its column 2; note 2 says the symbols are substantially identical to those of ISO 2575:2004. US Federal Motor Vehicle Safety Standard No. 101, Controls and displays (49 CFR 571.101): Cars, multipurpose passenger vehicles, trucks and buses sold in the US. S5.2.1: a control listed in Table 1 or Table 2 is identified by the symbol in column 2 or the word or abbreviation in column 3. S5.3.1(a): a control marked 'Yes' for illumination must have its identification lit whenever the headlamps are on, except on the floor, console, steering wheel, steering column or windshield header.
Good to know
- Unlike the demist symbols, the heating symbol has no frame.
Related dashboard pages
Other buttons under “Fans, air”
Sources
The symbol is cited to the regulation rows above; what pressing it does is taken from the owner's manual below. Each document was read on the date shown.
- UN R121: UN Regulation No. 121 (01 series) as published in the Official Journal of the EU, L 5, 8 January 2016, pp. 16-19: table 'Symbols, their illumination and colours' checked 2026-09-25
- FMVSS 101: govinfo: 49 CFR 571.101 in the Code of Federal Regulations, 1 October 2025 edition, Table 1 (pp. 329-332) and Table 2 (p. 334) as printed checked 2026-09-25
- SEAT Ateca owner's manual, UK English, edition 06.21 (model year 2022), PDF: Heating, ventilation and cooling; Troubleshooting; Auxiliary heating and ventilation, p. 147-148, 155 — Maximum heat output only at normal engine temperature; heating works best with a hot engine; auxiliary heater runs on fuel with the ignition off. checked 2026-09-25
Written in our own words; the manuals cover their own models only.