Checking for system leaks
- 1. If your boiler develops a leak, this should be fixed as soon as possible before the problem becomes worse and likely more expensive. It is not unusual for central heating boilers to develop leaks, when they do, they should be diagnosed early before more extensive damage is caused.
Common causes of leaks are:
- Failed seals or joints
- Cracked or split water carrying parts within the boiler
- 2. Things to keep an eye out for which could indicate your boiler has developed a leak
- Drips or dampness around and under the boiler
- Corrosion on the outside of the boiler and on the pipes
- If your boiler has a pressure guage, it may show a low water pressure
- 3. If you notice there is a leak, this is what you should do
- Catch the leaking water in a container to prevent any damage to the area around the boiler.
- Turn off the water supply at the boiler if you can.
- If isolating the water supply at the boiler fails to stop the leak, you may have to turn the off the mains water supply at the cold water stop tap and shut off the electricity supply to the boiler.
- Contact a registered Gas Safe engineer to inspect and repair the boiler.
- 4. If you have misplaced or lost your user manual, you can locate a replacement manual from this list of Vaillant boilers (please have your model number to hand).
- We update the maintenance tips and troubleshooting guidance from time to time and aim to make it as helpful as possible. The purpose of the maintenance and troubleshooting section of this website is to provide you with general guidance. Please ensure you read and follow our instructions carefully and do not undertake the maintenance or troubleshooting unless you are aged 18 or over, are competent to do so and are confident that you can complete the maintenance. If in doubt do not attempt any actions and where an appliance is gas fuelled refer to a Gas Safe engineer for assistance.
This website is not intended to be a substitute for professional advice and does not:
- cover every reason that your product could fail;
- cover all of the maintenance that can be undertaken for your product;
- supersede any advice in your instruction manual or from your product manufacturer.
Do not carry out any maintenance or use the troubleshooting guide if it puts you or anyone else in danger or if you believe it may cause damage to your, or another person’s property.