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Is Your Header Tank Overflowing? Find Out Why!

 When your header tank starts to overflow, you will need to find the problem and get an engineer out to fix it. Let Boilers Prices help you now!

If you have an open vented heating system in your home, then you will have a header tank. This tank is almost always found in the attic of your property, and it needs regular maintenance to keep it in good working order. However, there are times when a header tank can overflow, causing disruption to your home and heating. Find out more about the reasons for overflowing and how to avoid it here.

What Does a Header Tank Do?

You may have heard of a header tank being called a cistern or even the feed and expansion tank. No matter what the name, this tank is an integral part of your open vent heating system. The tank works to send water to the central heating and to provide a space for heated water as it expands. The reason that these tanks are stored in attics is that it is the highest point in the property and therefore supports the best water flow around the property.

Header tanks do not sit in isolation, they also have an overflow, cold feed and open vent pipes attached and a ball valve that connects to the heating system. 

Why is My Header Tank Overflowing?

When a header tank overflows it can be hard to work out what the cause is, meaning that you will need to call in a heating engineer to fix the issue. Fixing the header tank is not a DIY project as there are so many elements that can go wrong, cause damage and leave you out of pocket.

The three most common header tank problems are as follows:

  • Your pump has over run – when you switch off your heating, you will notice that your boiler continues to work for a couple of minutes. This stops the heat exchanger from overheating. However, if the valves have closed then the hot water will be pumped back to the header tank if the Automatic Bypass Valve isn’t doing its job properly. In this case, your engineer will need to check the ABV and reduce the settings so that it can stop the pump run over.
  • Faulty coils – in your hot water cylinder, there is a coil that supplies the central heating. This coil works to heat the water in the cylinder ready for use but this coil can become damaged, making holes that can raise the water levels and cause an overflow. The easiest way to work out if this is the problem for you is if your water is running a dirty brown or yellow colour. If this is the case, then an engineer will need to replace the cylinder.
  • Ball valve problems – if your ball valve is sticking then this can stop it from sending water to the system or sending water when it is not needed. In some cases, the ball valve can be repaired, but it is more likely that an engineer will advise a valve replacement for peace of mind.
  • Hot water escaping via overflow – if your overflow pipe has hot water coming from it then your float valve is not set correctly. You will need to switch off your heating system and then reset the float valve once the water is completely cooled.
  • Grime build up – as heating systems age, they experience a build-up of grime and dirt that can stop everything from working properly. This problem is not as problematic in new systems as the tank is lidded to stop the inlet of objects and dirt. However, if your system is grimy, you will need to switch off the mains and then carefully remove the dirt and clean the tank. An engineer can also complete this work for you if your tank is difficult to get to or if you do not want to do it yourself.

Is it Time to Consider a New System?

If your open vented system is causing you more hassle than you can stand, it may be time to think about other options, such as a sealed system. At Boilers Prices, we have guidance and advice on all types of systems so that you can work out which would suit you the best. We also offer a free comparison and quotation finder, helping you to get what you need with the help of expert heating engineers in your local area. Take a look today and enjoy hassle-free heating and hot water.