Buderus Error Code 0U Low Water Pressure +352 20 60 22 22 We
Buderus error code 0U: heating circuit pressure too low. How to refill yourself. When to call a heating engineer in Luxembourg.
Error code 0U on a Buderus boiler indicates that the water pressure in the heating circuit is too low (below 0.8 bar).
This is one of the few codes you can resolve yourself: locate the filling valve (blue pipe under the boiler), open it slowly until reaching 1.5 bar on the gauge, then close and reboot.
Warning: if pressure drops regularly (more than once a month), there is a leak in the circuit. Call Weber & Fils for diagnosis.
- Pressure loss diagnosis
- Circuit leak detection and repair
- Expansion vessel check
- Circuit refilling and balancing
- Preventive maintenance advice
FAQ
How to refill the Buderus circuit yourself (code 0U)?
Locate the filling valve (blue pipe under the boiler). Open it slowly to 1.5 bar on the gauge, then close. Reset the boiler. If the code returns quickly, call a professional.
What is normal pressure for a Buderus circuit?
A cold circuit should be maintained between 1.2 and 1.8 bar. Below 0.8 bar, the boiler triggers code 0U. When heating, pressure normally rises to 2-2.5 bar.
Why does my boiler pressure keep dropping?
Regular pressure drops indicate a leak: in a radiator, joint, fitting, or expansion vessel. Weber & Fils can detect and repair this leak.
Can code 0U damage the boiler?
The boiler stops as protection to avoid damaging the pump and heat exchanger. It won't operate until pressure is restored — this is normal protection.
Do I need a professional for Buderus code 0U?
Not always — if it's the first time, refill the circuit yourself. If the problem recurs, call Weber & Fils to find the leak: +352 20 60 22 22.