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Heating engineer · Brussels and Wallonia
Topping up your boiler pressure
Pressure drops a little over time, especially after bleeding the radiators. If the gauge needle is below 1 bar, you can usually top it up yourself in a few minutes.
Before you start
- Find the pressure gauge: a dial with a needle, or a reading on the boiler's display.
- Find the filling tap, usually under the boiler. Its shape varies by model: the manual shows it.
- Do it with the boiler cold: pressure rises as the water heats up.
Step by step
- Switch the boiler off or to frost protection.
- Slowly open the filling tap.
- Watch the gauge and close the tap when it reads between 1.5 and 2 bar.
- Check the tap is fully closed, then switch the boiler back on.
- If you've just bled the radiators, check the pressure once the pump has stopped and top up if needed.
Call us if…
- The pressure drops below 1 bar again within a few days: there's probably a leak.
- The pressure climbs close to 3 bar or water runs from the safety valve.
- You can't find the filling tap.
Based on the manufacturers' manuals (Oertli OEcOil Condens-2, notice d'utilisation 7658542). Every appliance has its quirks: if in doubt, your own manual applies.
A breakdown, a question? Get in touch.
Call us or message us on WhatsApp. Or leave your number, with a photo of the boiler if you like: we'll call you back.
