What Does Your Boiler Error Code Mean?
Enter your boiler model and fault code below for an instant plain-English diagnosis and step-by-step fix guide.
Low Water Pressure / Pressure Sensor Fault
Your boiler has detected that there isn't enough water pressure to fire up safely. This is a very common issue that usually just requires you to top up the system using the filling loop. However, if you have to do this frequently, there may be a leak or a faulty pressure sensor.
Step-by-Step Fix Guide
Check the pressure gauge on the front of your boiler. It should be between 1.0 and 1.5 bar.
Locate your filling loop (usually two valves underneath the boiler connected by a silver braided hose).
Slowly open the valves to let water in until the gauge reaches 1.5 bar, then close them tightly.
Press the reset button (often marked with a flame and a cross). The boiler should ignite normally.
If the error persists or pressure drops again within days, the sensor or expansion vessel may be faulty and need replacing.
How It Works
Diagnose your boiler problem in seconds. Free, no registration required.
1. Select Your Boiler
Choose your brand and model from our database of 40+ manufacturers and hundreds of boiler models.
2. Enter the Error Code
Type the exact code shown on your boiler display - our database covers all known fault codes across every model.
3. Get Your Fix Guide
Receive a plain-English diagnosis, a step-by-step repair guide, and direct links to the exact replacement parts you need.
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