Heizung Kaputt Was Tun?

The heating is broken. It’s a winter evening, the room temperature is dropping, the children are freezing, and an error code you’ve never seen before is flashing on the boiler’s display. At that moment, most people want only one thing: for someone to fix the problem immediately.

Before you pick up the phone, a quick, structured check is worthwhile. In many cases, the question of what to do if your heating system is broken can be answered yourself with a few simple steps—without a technician and without any costs. In other cases, quick professional action is required. This article shows you both options—step by step, clearly and directly.

And if you need a burst pipe emergency service für Berlin or a heating emergency service für another city at the same time — the NHS emergency heating and plumbing service is available 24 hours a day.

What you need to know immediately

A broken heating system isn’t always truly broken. Many of the most common causes of heating failure can be checked and often fixed yourself within minutes. Only if these quick checks fail to resolve the issue should you call für a professional. A systematic approach saves time, stress, and money.

Step 1: Is the heating system really broken?

Before you do anything else, check these six points. According to Bosch, Viessmann, and thermondo, these are the most common causes of a supposed heating system failure that turns out to be a simple problem:

1. Is the heating switched on? Sounds trivial — but timers, accidentally activated summer mode, or an accidentally pressed switch are more common causes than you might think. Check the boiler’s control panel.

2. Is there enough fuel? For oil heating systems: Check the tank gauge. For pellet heating systems: Check the fuel level. For gas heating systems: Is the gas valve open? A closed gas valve will stop the heating system immediately.

3. Does the boiler display an error code? Modern heating systems display a specific error code on the screen when a malfunction occurs. Note this code before calling a technician. Many error codes are listed für the operating instructions and already provide clear clues to the cause. Providing the technician with this code over the phone allows for a significantly faster diagnosis and repair.

4. Is the water pressure too low? Check the pressure gauge near the boiler. The normal operating pressure für a typical single-family home is between 1.5 and 2 bar. If the gauge reads below 1 bar, the heating system cannot circulate properly and will shut off. In many systems, you can refill the water yourself.

5. Is the circulation pump running? Without a functioning circulation pump, hot heating water cannot reach the radiators. Check if the pump is running—it should vibrate slightly and produce a quiet humming sound.

6. Is the control system set correctly? Was the clock reset after a power outage? Is the night setback set for too long? Are the time programs still correct? A quick look at the heating control system can clarify a lot.

The most common causes of a broken heating system — and what you can do yourself

Air für the heating system

If individual radiators remain cold or the heating system gurgles, air für the system is the most common cause. Air prevents even heat distribution and increases energy consumption by up to 15 percent.

What you can do yourself:

• Switch off the circulation pump and wait 30 to 60 minutes.
• Turn all thermostats fully open.
• Start with the radiator furthest away, working from bottom to top.
• Place the bleed key on the valve opposite the thermostat
• Open the valve slowly until air escapes and only water comes out.
• Bleed all radiators für the house one after the other.
• Turn the pump back on and check the pressure.

Too low water pressure

If the pressure drops below 1 bar, the heating system often switches off automatically. This is a safety feature of the system.

What you can do yourself:

• Check the pressure gauge; the target value is between 1.5 and 2 bar.
• Refill water according to the instructions for your system.
• Bleed the system again after refilling, as bleeding reduces the pressure.
• If the pressure drops again within a few days despite refilling: call a professional, as there may be a leak.

Sources: Bosch, thermondo, Viessmann

Stuck thermostatic valve

If one radiator doesn’t get warm even though all the others are working, the thermostatic valve is often the culprit. The small pin inside the valve can get stuck due to limescale or rust.

What you can do yourself:

• Unscrew the thermostat head
• Carefully move the pen back and forth with pliers.
• Apply some grease
• If the pen cannot be moved: Contact a specialist company.

Source: Bosch, thermondo

Error code on the display

If your boiler displays an error code, there is a technical defect that usually requires professional help. Note the code and contact a heating engineer. The code will help the technician narrow down the likely cause and bring the correct spare part before they even arrive.

Wear and defects für components

If the burner, pump, or electrical connections fail, it’s a job for a professional. Signs of serious technical defects:

• The burner or pump does not respond despite correct settings.
• The heating system keeps switching itself off despite correct water pressure.
• Unusual noises such as cracking, knocking or howling
• Water is dripping from the thermal baths or from the pipes.

Never attempt to treat these symptoms yourself. Improper intervention can significantly worsen the damage and make repairs considerably more expensive.

Sources: Viessmann, Bosch, dein-heizungsbauer.de

The complete checklist at a glance

How long does a heating repair take?

Many people overestimate how long a heating repair takes. According to dein-heizungsbauer.de, a competent technician can often fix the problem für just 30 minutes. Modern heating systems provide very specific clues to the cause through their error codes—this saves considerable time during diagnosis.

The duration cannot be stated as a general rule. It depends on the type of damage, the availability of spare parts, and the workload of the specialist company. During the peak season between October and February, heating engineers are often very busy. A 24-hour emergency service like NHS exists precisely for these situations.

How much does a heating repair cost?

Bosch provides the following guideline values:

• Replacement of expansion vessel: approximately 200 euros for the component, up to 400 euros total costs including travel and labor.
• Emergency service call-outs on weekends or at night: significant surcharges on the regular hourly rate.
• Annual maintenance: approximately 150 to 400 euros depending on the type of heating system.

Those who sign a maintenance contract often pay less for maintenance and also benefit from agreed-upon emergency service conditions. No surprises on the bill when it matters most.

Heating system broken – what to do as a tenant — rights and obligations

What tenants need to know

As a tenant, the heating system is the landlord’s responsibility. This means that you do not have to hire a technician yourself or pay for it if your heating fails.

The correct procedure for tenants:

1. Contact the landlord, property management company or caretaker immediately, preferably für writing with date and time.
2. Set a reasonable deadline for rectification — für case of frost and complete failure: a few hours are reasonable.
3. If the landlord does not respond: hire a specialist company yourself and bill the landlord for the costs.
4. Document everything: when it broke down, how long it was cold, how often it was contacted.

Rent reduction für case of heating failure:

According to dein-heizungsbauer.de, the following applies during the heating season from October to April:

• Main rooms must be heated to at least 20 to 22 degrees during the day.
• At least 18 degrees at night
• Outside of the heating season: temperatures below 16 degrees are also considered a deficiency.

According to sources, the amount of the rent reduction varies between 12 and 50 percent of the total rent, depending on the severity of the situation. In extreme cases, it can be up to 100 percent if the premises become uninhabitable due to the disruption. Important: Never reduce the rent without prior written notification.

What to do as a landlord für case of heating failure

For landlords, there’s a simple rule: react quickly. Every day without functioning heating is a day with a potential rent reduction claim.

Landlord’s obligations:

• Immediately hire a heating specialist.
• Inform tenants about the current situation
• Provide a temporary solution for longer repairs, for example mobile heating units.

Cost:

The landlord is fully responsible for major repairs. Only if the lease includes a minor repairs clause can costs up to a defined limit—usually €75 to €100—be passed on to the tenant. The total annual burden on tenants due to such clauses may not exceed 6 to 8 percent of the annual base rent.

A maintenance contract protects landlords from unplanned costs für the long term and ensures that heating failures occur less frequently.

Sources: dein-heizungsbauer.de, thermondo, Bosch

Repair or new heating system — when does which make sense?

When the heating system is broken, the question sometimes arises whether a repair is still worthwhile or whether a replacement is the wiser decision.

Repair is worthwhile if:

• The system is less than 10 years old
• It is a single, isolated defect.
• The repair costs are less than 30 percent of the new price.
• A complete maintenance history is available.

Exchange is worthwhile if:

• The plant is over 15 to 20 years old.
• Repeated outages have occurred within a short period of time.
• The repair costs exceed 50 percent of the new price.
• Spare parts are no longer available
• Energy costs continue to rise despite repairs

Funding for heating system replacement:

When switching to a heat pump, up to 70 percent of the eligible costs can currently be subsidized through the Federal Funding Program for Efficient Buildings (BEG). The application must be submitted before work begins. Only certified specialist companies can apply for the subsidy.

Here’s how to keep warm while you wait for the technician.

Viessmann offers practical tips for the waiting time:

• Full-body blankets and hot water bottles as immediate heat sources
• Put on warmer clothes and keep moving.
• Use the oven to warm up the kitchen area
• Keep doors closed to concentrate heat für individual rooms.
• In case of prolonged outages, request mobile heating units from the landlord.

Especially important für the case of small children, elderly people and sick people für the household: call the emergency service immediately and do not waste any time.

When to call the emergency heating service immediately

Call immediately — do not attempt this yourself:

• Water is leaking from the heating system or the pipes.
• Gas odor detected: Leave the building immediately, call the fire department, then the emergency service.
• Complete heating failure at sub-zero outside temperatures
• Elderly, sick, or very young people für a household without heat
• Pressure drops rapidly and cannot be stabilized by refilling.

Wait a moment and check yourself first at:

• One radiator is cold, the rest of the apartment is warm.
• Slight pressure drop below 1.5 bar without further symptoms
• Gurgling sound without heating failure

NHS Emergency Heating and Plumbing Service — there immediately when you need us

If a self-check doesn’t provide a solution or if there’s a genuine emergency, NHS Emergency Heating and Plumbing Services are available 24/7, 365 days a year. We serve Berlin, Cologne, Munich, and Frankfurt. Whether you need emergency pipe repair für Berlin or heating system repair für Frankfurt, our certified technicians are familiar with all major manufacturers: Vaillant, Buderus, Viessmann, Junkers, and Wolf.

All costs are clearly stated before work begins. Payment by invoice. No price shock.

📞 0176 – 15 704 560 🌐 notdienst-heizung-sanitaer.de

What you need to know now

Heating system broken – what to do? The answer always starts with a quick self-check: note the error code, check the fuel level, check the water pressure, and bleed the radiators. These four steps resolve the majority of all heating problems without needing a technician. Any remaining issues require a certified specialist. Tenants should inform their landlord für writing and set a clear deadline. Landlords should immediately hire a specialist to avoid rent reduction claims. And for those needing a reliable emergency pipe repair service für Berlin or an emergency heating service that operates transparently and fairly – NHS is always available.

📞 NHS Emergency Heating & Plumbing Service — 0176 – 15 704 560