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What should I do in case of a defect?

Sometimes you are capable of fixing a defect yourself should it occur. Please always first check the points below before contacting us. This way, you can avoid unnecessary costs.

The defect resolution checklist

•  If your central heating boiler or combination boiler has a power plug, then check whether mains voltage is present on the outlet. This could also work for so-called closed geysers. For instance, connect another appliance to the outlet. Is there voltage or not? Check the fuse in the meter cupboard.


•  Are the gas valves under the boiler open? How about the mains in the meter cupboard?


• Does the water pressure in the central heating system read more than 1 bar? If not, add water until the pressure reads no more than 1.8 bar (refer to ‘filling up’).


•  Set the room thermostat to at least 30°C and see whether the boiler switches on. If this is the case, then check whether the gas appliance reacts to the proper settings for about 3 days. Is the boiler not switching on? Report it as a defect.


•  Does the pilot light work? If this is not the case, then relight it. You may have to keep an eye on the flame for a while.

•  If your thermostat is equipped with batteries then the display will indicate whether these need replacing. Only alkaline batteries are permitted.


•  Reset the appliance if this is possible. Pulling the plug and plugging it back in may also work. Important: write down the defect or failure code that is displayed and pass it on when reporting the defect.


•  If no hot water is coming out of a tap while another tab is providing hot water, then the chances are that the perlator (the little sieve) or the showerhead is clogged up. Clean it with vinegar and check whether the system then works.


•  It is possible that you have hot water but that the central heating system doesn't work. Check whether one of your hot water taps is dripping. This will cause the central heating boiler to retain its hot water position and not switch to central heating.

Have you checked the above points?

If the defect still persists please contact us as soon as possible. You can call us on +31 (0)20 614 80 90