Vaillant Eco Tec Combination Boiler Common Hot Water Problems

The Vaillant Eco Tec combination boiler is a state of the art appliance designed to give the user constant hot water and heating as and when it is needed.

There are many different models to choose from depending on what your needs maybe.

A common problem that happens over time with most combination boilers, and not just with Vaillant boilers is lack of hot water. It starts off with the temperature modulating going hot and cold, eventually stopping altogether.

As we are discussing the Vaillant Eco Tec Boiler I will take you through a couple of simple procedures to check before you call in your local gas safe boiler engineer.

First we need to check that boiler has sufficient pressure to work to heat the water. On the front of the boiler, normally on the bottom right side you should see a pressure gauge, this should read around 1.2bar or just above the red area into the grey section.

The pressure can also be checked from the digital display window, press any button on the panel, the internal blue light will come on, now press the button directly below the radiator symbol, you will now see a bar symbol, press the same button again and you will see the digital pressure. This is another way to check the pressure if you think the gauge is not working properly.

If the pressure is correct we now need to move onto the next check, open a hot water tap that is closest to the boiler, now check the boiler display, a tap symbol should be displaying. If there is no tap symbol displaying then the aqua sensor maybe at fault and will need to be checked by a boiler engineer.

If the symbol is displaying then we know the boiler is in hot water mode and the boiler should fire up to heat the water.

As the boiler is heating the water you should see the temperature on the display start to rise gently, if it rises very quickly and the boiler then shuts down, the temperature should fall and the boiler will then start up again.

If this is happening to your Vaillant Eco Tec then the boiler is overheating and shutting down to stop any internal damage. This problem is normally due to the hot water heat exchanger becoming blocked or partially blocked with sludge.

If the above seems familiar with your boiler, whatever make it maybe, you will need to contact a boiler engineer to replace the hot water heat exchanger, and to flush the system out and then add inhibitor to stop this happening again.

Another problem that happens with many boilers and not just the Vaillant Eco Tec is the hot water only works when the central heating is on. This problem is normally due to the diverter valve either being stuck in the heating mode or is faulty and will need to be replaced.

All boilers whatever make or model these days need to have regular maintenance, and one of the important checks that needs to be carried out is to check that system has enough inhibitor in the water. It’s always best to top the inhibitor up every time the annual service is carried out. Inhibitor will prevent sludge forming within the system.

Sludge is the common killer of hot water heat exchangers in all makes of boilers and not just the Vaillant Eco Tec.

All boilers if maintained properly should be trouble free, but occasionally things do happen. Around 90% of boiler breakdowns are normally due to other faults and not the boiler. They shut down to protect themselves from damage.

If you are starting to experience problems with your hot water that is heated through a combination boiler, I would advise you to call someone in to check the boiler over, don’t leave it too long as it could become very expensive to repair.