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Worcester Bosch Boilers: Fault & Error Codes

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Worcester Bosch Boilers: Fault & Error Codes

There is no ‘right’ time for your boiler to break down. Nor is the event ever stress-free. The first step to fixing a problem is by identifying what could be wrong with the boiler. Sometimes you can make this assessment yourself, but a professional eye will give you an official diagnosis.

In this article, we’ll be covering the top 10 boiler problems, and highlighting the telltale signs of each malfunction alongside our infographics for Worcester Bosch Boilers: Fault & Error Codes.

Worcester Bosch Blocking Error Codes infographic


Everyone recognises the familiar whistle of a kettle, but what if that noise is coming from your boiler? The root cause of this can be sludgy deposits building up in your boiler – the consequential lack of water can then overheat the existing water and, in effect, boil it. If your boiler is continually making this sound, it is wise to arrange a system flush with a professional.

Strange Noises

Kettling isn’t the only strange sound a boiler can make. Gurgling and banging have also been reported by homeowners. Causes of this can vary, and include sludge or air build-up, or possible pump failure. Only an expert can determine the precise cause of the noises.

Boiler Switches Off

You may feel as though your boiler has a mind of its own,  especially if it keeps switching itself off. The causes can vary hugely, and range from deposit and air build-up to an issue with pressure or individual components. Your best chance of diagnosis is for a professional to cast their eye over the situation.

Radiators Staying Cold

Worcester Bosch Blocking Error Codes infographic 2

If you’re desperate for a bit of heat, but your radiator is just not playing along, it can be incredibly frustrating. A radiator that is slow to heat up, or just doesn’t heat up at all, could be indicative of sludge or air build-up. One thing you can do is bleed or balance your radiators – this can be done at home without the need for a professional. If these techniques don’t resolve the issue, however, you may need to call a specialist to flush your system out.

Pilot Light Is Out

The pilot light is what keeps a boiler ticking over, and can be identified as a blue flame. Occasionally, this may go out and you can relight it yourself, but if it’s becoming a repeat problem, this will need examining more closely. The gas supply may be restricted or perhaps a deposit has built up in the pilot light. A Gas Safe engineer, such as those at A&D Plumbing, will need to take a closer look.

No Heating/Hot Water

Having no hot water or heating will disrupt the smooth running of your home. Your first port of call should be to check that your thermostat is working correctly, and that your boiler pressure is correct. If everything seems to be fine, call out an expert to identify the precise cause.

A Leaking Boiler

If you notice liquid leaking from your boiler, you will first need to establish exactly where the water is coming from. The most likely cause is a faulty component, such as the pump seal, which can be resolved through repair or replacement. Corrosion or a poor boiler fitting are other possible reasons.

Low Pressure

All boilers come kitted out with a pressure gauge, allowing you to check whether your boiler pressure has dropped to an alarming degree. If the needle is below 1, this could be problematic. Causes of this low pressure include a leak or wearing down of the pressure valve. However, this issue can also occur just after you have bled a radiator, so bear this in mind.

The Condensate Pipe Has Frozen

When a condensate pipe has frozen, a boiler error code should present itself. But what do condensate pipes look like? They are usually identified as a plastic white pipe that leads to a drain on the outside of your property. Chances are you may be able to thaw it out yourself with some hot water, before resetting your boiler.

Unruly Thermostat

Have you noticed your thermostat turning itself off or not adhering to the preset schedule? Firstly, check for human error such as whether it’s been knocked or if the settings have been changed by another household member. If a person isn’t to blame, it could just need replacing with a newer model.

Worcester Bosch Blocking Error Codes infographic 3

Get an expert opinion on your boiler issues with help from A&D Plumbing Services. As reliable and accredited professionals, we understand the ins and outs of all major boiler brands like Baxi & Worcester boilers – this helps us swiftly diagnose and repair any boiler issues. Contact our team today for some friendly advice – we serve a wide area, including Essex, Sussex and Cambridgeshire. Call us on: 0800 0214 751


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