Vaillant Boiler Fault Codes, Manuals & Expert Support
Vaillant Boiler Technical Support: Fault Codes & Troubleshooting
Vaillant boilers, including the flagship ecoTEC plus and ecoTEC exclusive ranges, are the gold standard for German-engineered heating. However, even the most reliable systems require expert maintenance to stay efficient.
At Thermotec Plumbing and Heating, we provide specialist support for Vaillant systems across Wokingham, Earley, and Shinfield. Whether you are dealing with a sudden breakdown or looking to optimise your system's flow temperature, our Gas Safe engineer is here to help.
Expert Vaillant Boiler Servicing & Repairs in Wokingham
Need a reliable Vaillant engineer in Wokingham, Earley, or Shinfield? At Thermotec Plumbing and Heating, we specialise in the entire Vaillant ecoTEC range. Whether your boiler has locked out with an F22 pressure fault or requires its annual Gas Safe service to protect your warranty, we provide fast, local, and expert support.
We don’t just "check" your boiler; we perform a full technical diagnostic to ensure your system is running at peak efficiency, saving you money on your monthly energy bills and preventing costly winter breakdowns.
Common Vaillant ecoTEC Fault Codes
If your Vaillant boiler is showing a flashing light or an 'F' code, it is protecting itself from damage. Here are the most common codes we resolve:
F.22: Low water pressure. Often caused by a leak or a failing expansion vessel.
F.27 / F.28 / F.29: Ignition faults. This could be a gas supply issue or a blocked condensate pipe.
F.75: Faulty pump or pressure sensor. A common issue if the system has magnetite sludge buildup.
F.32: Fan fault. Usually requires a technical inspection of the air/flue duct.
Why Choose Thermotec?
The Wokingham Vaillant Specialists
Advanced Diagnostics: Expert troubleshooting for all 'F' codes (F22, F28, F75, etc.).
Warranty Protection: Full servicing in line with Vaillant’s strict manufacturer requirements.
Genuine Parts: We prioritize high-quality, manufacturer-approved components for all repairs.
Transparent Pricing: Local, family-run service with no hidden "national company" fees.
Fully Gas Safe: Registered and insured for your total peace of mind.
Vaillant Boiler Manuals
Need a manual for your Vaillant boiler? Browse our selection of downloadable PDF manuals for current and older models. Manuals include user settings, error code explanations, and maintenance guidance.
Popular Vaillant Models
Other Vaillant Models
Frequently Asked Questions: Vaillant Boiler
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The F.22 fault code is one of the most common issues and indicates low water pressure. This usually happens if there is a leak in the system, or if you have recently bled your radiators. You can often resolve this by topping up the pressure via the filling loop, but if it drops frequently, you may have a failing expansion vessel or a hidden leak that requires a professional inspection.
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An F.75 fault suggests a faulty pump or pressure sensor. The boiler tries to start the pump but doesn't detect a rise in pressure. This is very common in systems with magnetite sludge buildup, which clogs the sensor. While resetting might work temporarily, it usually requires a sensor replacement or a system power flush to prevent a total pump failure
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Both F.28 and F.29 are ignition faults, meaning the boiler isn't receiving gas or cannot maintain a flame. In winter, this is often caused by a frozen condensate pipe. Other causes include a faulty gas valve or a blocked spark electrode. If your condensate pipe isn't frozen, you must call a Gas Safe engineer to check the internal gas components.
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To reset a Vaillant boiler, look for the button with a flame symbol with a cross through it (or a button labeled 'Reset'). Press and hold it for 3-5 seconds. If the fault code returns immediately, do not keep resetting the boiler; this indicates a persistent safety issue that needs a professional diagnostic.
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"Kettling" is usually caused by limescale or sludge buildup on the heat exchanger. While not immediately dangerous, it makes your boiler highly inefficient and will eventually lead to a cracked heat exchanger (an expensive repair). We recommend a system cleanse or power flush to restore quiet, efficient operation.