No hot water from your Bulex boiler: useful checks before calling

HEATING ADVICE · BRUSSELS

Bathroom tap with running water — Identify which outlets are affected before describing the fault. Illustrative image.

Practical advice · 5 October 2026

Is the shower cold while the radiators still work? Or has your Bulex boiler stopped providing both heating and hot water? These situations call for different observations. A clear description helps a heating professional prepare the visit without risky attempts at DIY repair.

Illustration of gloved hands during boiler maintenance

One outlet or the whole home?

Identify where the problem occurs: shower, kitchen sink, basin or every hot-water outlet. Describe whether the water stays cold, becomes lukewarm or alternates in temperature. Avoid testing at excessive temperatures because of the risk of scalding.

A problem at just one outlet does not automatically mean the boiler is faulty. The tap or a local part of the installation may need assessment. If every outlet is affected, describe how the overall hot-water system behaves and whether anything has recently changed.

Check the display without opening the boiler

Note whether the appliance is switched on and whether a message appears during a hot-water demand. Consult the manual for user-accessible settings such as operating mode, hot-water setpoint and any separate-cylinder schedule. Do not enter installer-only menus.

Record the exact boiler model and complete fault code, including letters and numbers. Interpretation depends on the appliance. A fault message can guide a diagnosis but cannot, on its own, confirm a failed part. See our Bulex repair service to prepare your enquiry.

Illustration of a boiler display with a warning symbol

Information that helps the contractor

Does central heating still work?
Is the hot-water problem constant or intermittent?
Did it start after a power cut or work on the system?
Do you have a combination boiler or a separate cylinder?
Does the temperature change when several taps are used?

Your answers describe the symptoms; they do not replace professional measurements. Do not dismantle the boiler or its connections. If a fault returns, avoid repeatedly restarting the appliance.

Prepare the repair and check the result

For a visit in Jette, Anderlecht or elsewhere in Brussels, provide your address, Bulex model reference and a photograph of the display. The contractor can explain the initial on-site checks and the terms of the visit.

After the repair, ask for hot water to be checked under the conditions that previously caused trouble. If comfort has become inadequate because household needs have changed, an assessment of the installation may be more useful than replacing a part without a diagnosis.

Frequently asked questions

Can there be a boiler fault if the radiators still heat up?

Yes, but this observation does not identify a specific part. Tell the contractor that the problem appears limited to hot water.

Should I turn the temperature much higher?

No. An excessive setpoint does not solve a fault and increases the risk of scalding. Follow the manual and professional advice.

What if I smell gas?

Stop testing the appliance, do not operate electrical switches and do not use a flame. Leave the premises and contact the gas emergency service from outside.

Questions about your Bulex boiler?

Tell us what is happening, your municipality and your appliance model. We will help you prepare the next step.

Call the heating specialist · 0499 00 13 10 Request a visit