Heating in Germany: What the Thermostat Numbers Mean and the German You Need
Heating in Germany is mostly done with radiators (Heizkörper) controlled by a thermostat knob from 1 to 5. Setting 3 means roughly 20 °C room temperature, and each step changes it by about 3 to 4 °C. Turning the knob to 5 does not heat the room faster; it only lets it get hotter, up to around 28 °C.
The knob is not a tap that controls how much hot water flows; it is a thermostat that closes the valve when the room reaches the target temperature. Below: the numbers, when the heating season starts, how to air your flat without causing mould, the main heating systems, what to do when the heating or hot water fails, what heating costs, and the German phrases for talking to your landlord or neighbours.
This is general information for rented flats in Germany, not legal advice. Austria and Switzerland have their own tenancy rules and customs.
What do the numbers on a German heater mean?
The values below are the approximate guide values published by co2online, a non-profit energy advice organisation. Real temperatures depend on the radiator, the room and where the thermostat sits.
| Symbol on the knob | Approx. room temperature | Typical use |
|---|---|---|
| * (snowflake / star) | about 6 °C | frost protection, e.g. cellar or when you are away |
| 1 | about 12 °C | stairwell, unused room |
| ☽ (moon, on some models) | about 14 °C | night setback |
| 2 | about 16 °C | bedroom |
| 3 | about 20 °C | living room, kitchen, home office |
| 4 | about 24 °C | bathroom |
| 5 | about 28 °C | maximum |
Three practical rules:
- Do not turn it to 5 to warm up faster. The radiator does not get hotter more quickly; it just keeps running longer, and you pay for heat you did not need.
- Do not cover the thermostat with curtains or furniture. Warm air collects around it, the valve closes early and the room stays cold.
- Use the snowflake when you go away in winter, so pipes do not freeze, instead of turning the heating completely off.
If the radiator stays cold or gurgles
A radiator that is warm at the bottom and cold at the top, or that makes a gurgling noise (gluckern), often has air in it. Many tenants bleed it themselves with a small radiator key (Entlüftungsschlüssel) from a hardware store; if you are unsure, ask the landlord or caretaker first. If all radiators in the flat stay cold, it is a problem for the landlord.
When do you turn on the heating in Germany?
There is no single law with a date, but the German Tenants’ Association (Deutscher Mieterbund) says the heating period starts on 1 October at the latest. From then, it says, landlords must make sure flats can reach at least 20 to 22 °C between 6:00 and 24:00, and about 18 °C at night. These figures come from court decisions, and individual contracts and cases differ; if your flat stays cold, a local Mieterverein can advise you.
Inside the season, you decide yourself when to heat. The Verbraucherzentrale suggests heating living rooms and bedrooms to at least 16 to 18 °C during the day, even rooms you rarely use, because cold rooms are where mould starts. Its general comfort range is about 18 to 22 °C.
Airing your flat: Stoßlüften, not Kipplüften
Germans are serious about airing (lüften), and landlords often mention it in the contract or house rules because damp air causes mould (Schimmel).
| Method | What it means | Verdict in winter |
|---|---|---|
| Stoßlüften | open windows fully for a few minutes | recommended |
| Querlüften | open windows on opposite sides for a draught | even faster |
| Kipplüften | leave a window tilted for hours | cools the walls, wastes heat |
The Verbraucherzentrale recommends a full air exchange at least three to four times a day; in winter three to five minutes with fully open windows are enough. Turn the thermostat down while the window is open. Ideal indoor humidity is about 40 to 60%; if it stays above 50% for a long time in winter, or the windows fog up on the inside, air more often. A cheap thermo-hygrometer shows you both values.
Types of heating in German flats
| German | English | How it works for you |
|---|---|---|
| die Zentralheizung | central heating | one system for the whole building; costs on your annual statement |
| die Etagenheizung / die Gastherme | flat-level gas boiler | a boiler in your flat (often kitchen or bathroom); you may pay gas directly to a supplier |
| die Fernwärme | district heating | heat delivered from a city network; billed through the landlord |
| die Wärmepumpe | heat pump | electric; more common in newer buildings |
| die Fußbodenheizung | underfloor heating | reacts slowly; change settings in small steps |
| die Nachtspeicherheizung | night storage heater | electric heaters in some older flats |
With central heating you usually pay monthly advances and get the real bill once a year. How that bill is split between consumption and floor area is in Nebenkostenabrechnung explained. With an Etagenheizung on your own gas contract, the gas supplier bills you directly; the setup steps are similar to those in setting up electricity in Germany.
Safety: if you smell gas, do not switch on lights or use anything that could spark, open the windows, leave the flat and call the emergency number of your gas supplier or network operator from outside. In any emergency with danger to life, or fire, call 112.
How much does heating cost in Germany?
The Heizspiegel 2026, published by co2online in September 2026, gives these average annual heating costs for a 70 m² flat in a multi-family building:
| Heating type | Billing year 2025 | Forecast 2026 |
|---|---|---|
| Natural gas | 1,170 € | 1,120 € |
| Heating oil | 1,030 € | 1,275 € |
| District heating | 1,295 € | 1,310 € |
| Heat pump | 715 € | 735 € |
| Wood pellets | 735 € | 860 € |
Your own costs depend on insulation, floor, building age and how you heat. According to co2online, each degree lower saves about 6% of heating energy, so going from 22 to 20 °C makes a visible difference on the next bill.
What can I do if my apartment has no hot water?
- Check your flat. With an Etagenheizung, look at the boiler display: an error code or low pressure (Druck) is common. Write down the code.
- Ask a neighbour whether they also have no hot water. If the whole building is affected, it is a central problem.
- Report it to the landlord or Hausverwaltung in writing, with date and time. Outside office hours, many buildings list an emergency service (Notdienst) in the stairwell.
- Keep a record of how long it lasted. The step-by-step German for reporting defects is in reporting a problem to your landlord.
Saying it out loud is harder than writing it. SipLingo lets you practise conversations like calling the Hausverwaltung by voice, and corrects your grammar and word order in your own language, with the right sentence and an example. Practise the call.
Message template: heating or hot water broken
Betreff: Heizung / Warmwasser defekt – [Straße, Nr., Etage], [Name]
Sehr geehrte Damen und Herren,
seit [Datum, Uhrzeit] funktioniert in meiner Wohnung die Heizung nicht. Es gibt auch kein warmes Wasser. Die Therme zeigt den Fehlercode [Code]. Meine Nachbarn im [Stockwerk] haben das gleiche Problem.
Bitte schicken Sie so schnell wie möglich einen Techniker. Ich bin unter [Telefonnummer] erreichbar und morgen ab 8 Uhr zu Hause.
Mit freundlichen Grüßen
[Name]
Translation: Subject: Heating / hot water broken – [address], [name]. Dear Sir or Madam, since [date, time] the heating in my flat has not been working. There is also no hot water. The boiler shows error code [code]. My neighbours on the [floor] have the same problem. Please send a technician as soon as possible. You can reach me at [phone number], and I am at home tomorrow from 8 a.m. Kind regards.
Dialogue: asking a neighbour
Sie: Hallo, entschuldigen Sie. Funktioniert bei Ihnen die Heizung?
Nachbarin: Nein, bei uns ist es auch kalt. Seit heute Morgen.
Sie: Haben Sie schon die Hausverwaltung angerufen?
Nachbarin: Ja, aber da ist niemand ans Telefon gegangen.
Sie: Ich schreibe eine E-Mail und rufe den Notdienst an. Die Nummer hängt unten im Flur.
Nachbarin: Gute Idee. Sagen Sie Bescheid, wenn Sie etwas hören?
Sie: Ja, klar. Ich klingle bei Ihnen.
Translation: “Hello, excuse me. Is your heating working?” “No, it’s cold at our place too. Since this morning.” “Have you called the property management yet?” “Yes, but nobody answered the phone.” “I’ll write an email and call the emergency service. The number is on the notice downstairs in the hallway.” “Good idea. Will you let me know if you hear anything?” “Yes, of course. I’ll ring your bell.”
Vocabulary table
| German | English |
|---|---|
| die Heizung | heating |
| der Heizkörper | radiator |
| das Thermostat / der Thermostatkopf | thermostat / thermostat knob |
| die Heizperiode | heating season |
| die Therme | (gas) boiler |
| der Heizkostenverteiler | heat cost allocator (device on the radiator) |
| das warme Wasser / das Warmwasser | hot water |
| lüften / das Stoßlüften | to air / short full airing |
| der Schimmel | mould |
| die Luftfeuchtigkeit | humidity |
| entlüften | to bleed (a radiator) |
| der Notdienst | emergency service |
| die Heizkostenabrechnung | heating cost statement |
Useful phrases
- Die Heizung wird nicht warm. – The heating doesn’t get warm.
- Der Heizkörper gluckert. – The radiator is gurgling.
- Wir haben kein warmes Wasser. – We have no hot water.
- Ab wann wird die Heizung angestellt? – From when will the heating be switched on?
- In der Ecke ist Schimmel. – There is mould in the corner.
- Wie stelle ich die Therme ein? – How do I set the boiler?
Why is air conditioning rare?
Most German flats have no air conditioning (die Klimaanlage). Common explanations are the climate in most regions, building traditions and energy costs, and in rented flats you usually need the landlord’s permission before installing a fixed unit. In summer, people keep shutters (Rollläden) down during the day and air the flat at night or early in the morning. If you are choosing a flat, ask about heating type and costs at the viewing; questions are in apartment viewing in German.
Checked in October 2026 against co2online (thermostat guide values, Heizspiegel 2026), the Verbraucherzentrale (heating and airing advice) and the Deutscher Mieterbund (heating period, October 2026).
Official sources
For the official details and the latest updates, see:
- Umweltbundesamt (UBA): Heating right: room temperatures and airing (German) – 20 °C living, 17 °C bedroom, thermostat level 3, Stoßlüften
Frequently asked questions
How do heaters in Germany work?
Most flats have radiators connected to central heating or a gas boiler, each with a thermostat knob. The knob sets a target room temperature; the valve closes automatically when the room reaches it.
What do the numbers on a German heater mean (Was bedeuten die Zahlen am Thermostat)?
They are temperature levels, not flow levels: roughly 1 = 12 °C, 2 = 16 °C, 3 = 20 °C, 4 = 24 °C and 5 = 28 °C, with the snowflake for frost protection at about 6 °C. Real values depend on the room.
When do you turn on the heating in Germany?
The Deutscher Mieterbund says the heating period starts on 1 October at the latest, and landlords must make about 20 to 22 °C possible during the day. Within the season, you heat whenever you need to.
What can I do if my apartment has no hot water?
Check the boiler display if you have one, ask neighbours whether they are affected, then report it in writing to your landlord or Hausverwaltung with date and time. Outside office hours, use the emergency number posted in the building.
How much does heating cost in Germany?
According to the Heizspiegel 2026, a 70 m² flat cost on average about 1,170 € a year with gas and 1,295 € with district heating in 2025, and about 715 € with a heat pump. Your bill depends on the building and your habits.
Call your landlord without panic: practise the German first with real voice conversations and instant corrections.
