Bosch Group · Founded 1932 · Leader in Spain
Repair and spare parts for Junkers boilers in Madrid
Specialised technical service for the entire Junkers range in Madrid and the metropolitan area. Diagnosis, repair, and spare parts for condensing boilers, water heaters, and air conditioning systems.
💡 Direct response
Junkers It is a German brand of boilers and water heaters from the Bosch Group (founded 1932). The most widespread in Spain, with equipment in millions of homes. Their condensing boilers reach up to the 109% efficiency. Common ranges in Madrid: Cerapur (condensation), Eurosmart / Eurostar și Ceraclass.
🏆 Bosch Group
Guaranteed supply of spare parts for 10 years after each model is discontinued.
⚡ Up to 109% efficiency
Cerapur A+ class boilers. Compatible with Bosch smart thermostats.
📦 Spare parts in stock
Original and equivalent. Express shipping 24-48h throughout Spain.
Junkers product range
Gas boilers
- Cerapur (ZWB, ZWBC, ZSB) — A+ class condensing. More widespread in new construction.
- Eurosmart / Eurostar (ZWA, ZWE, ZWBE) — forced draught. Widely installed in Madrid 2000‑2015.
- Ceraclass (ZWC, ZRC) — mid-range. Balanced efficiency and cost.
- Turbotherm — classic and robust. Still in operation in many Madrid homes.
- Novastar / Heatronic — current range with digital panel and Bosch Smart Home integration.
Domestic water heaters
- Hydrocompact (WTD 11‑18‑24) — high power, electronic ignition.
- Aquaplus / Aquapoint — compact for small homes, low standby consumption.
- Minimaxx / Top Plus — sealed forced draught, widely used in Madrid.
- Hydro Next — current generation with digital display and automatic adjustment.
Most common fault codes
The display shows a code when it detects a fault. Identifying it before calling speeds up the diagnosis:
| Code | Meaning | Common cause |
|---|---|---|
| F1 | Low pressure | Water leak, expansion vessel or filling valve |
| EA | Ignition fault | Electrode, gas valve, or control board |
| E9 | Overtemperature | NTC sensor, circulator stopped |
| F7 | Flame fault | Ionisation electrode or PCB |
| F5 | Sensor out of range | Heating or DHW NTC sensor faulty |
| 133 | Fan fault | Ventilation fan blocked |
| DF | Spontaneous flame | Gas valve or ionization sensor |
Junkers spare parts: own stock and 24h delivery
Stock of the most demanded spare parts. Unavailable parts located and shipped in 24-48 hours home delivery throughout Spain:
- Control boards
- Circulator pumps and hydraulic groups
- Flow meters, pressure switches, and NTC sensors
- Gas valves and three-way valves
- Extractors, fans, and electrodes
- Plate heat exchangers and bithermal heat exchangers
Frequently Asked Questions about Junkers Boilers
The most common questions we receive, answered clearly:
Junkers is a German brand founded in 1932, today integrated into Bosch Thermotechnology (Bosch Group). It is the domestic heating brand with the largest presence in the Spanish housing market. Bosch guarantees spare parts for at least 10 years after each model is discontinued.
With annual maintenance, a Junkers boiler can operate between 15 and 25 yearsCondensing models like the Cerapur have greater complexity but also higher efficiency. The classic atmospheric series (Eurosmart, Turbotherm) are known for their robustness as long as they are maintained periodically.
As a guideline: if the repair exceeds the 40–50% of the cost of an equivalent new boiler and if the equipment is more than 15 years old, it is usually more cost-effective to replace it. For equipment less than 10 years old, repair is almost always the economical option. Contact us and we will guide you before you decide.
Short cycling occurs when the boiler reaches temperature very quickly and shuts off, only to turn back on soon after. Common causes: worn-out circulating pump, depleted expansion vessel, closed zone valves, or miscalibrated NTC sensor. Requires measurement during operation.
The Cerapur (ZWB, ZWBC) is high-efficiency condensing, recovering heat from the gases and achieving up to 109% efficiency on LCV, class A+. The Ceraclass It is standard, simpler, and more economical to install but without condensation. In new construction, regulations promote condensation.
The manufacturer's recommendation and Spanish regulations are an annual inspectionIn communities and commercial premises, it may be mandatory with a certificate. Maintenance includes cleaning the burner, checking pressure, inspecting seals, and issuing the certificate. It prevents serious faults and maintains efficiency.
The model is in the rating plate of the boiler (lower front part, side, or front cover). Include reference, power in kW, and serial number. If you can't find the plate, send us a photo from our section of contact and we help you identify it.
Does your Junkers equipment need servicing?
Please provide the model and the fault code if it appears on the panel. We will guide you before the visit.