Vaillant Ecotec Plus 618 Problems

The Vaillant ecoTEC Plus 618 boiler is renowned for its reliability and efficiency. However, like any machine, it can occasionally experience issues. In this article, we’ll look at a particular problem faced by many Vaillant ecoTEC Plus 618 users and provide solutions to address these challenges.

Problem: Boiler Losing Pressure

A commonly reported issue with the Vaillant ecoTEC Plus 618 is the loss of pressure, which affects both heating and hot water. Some users reported having to regularly top up the water every few days due to this problem. While this might appear as an isolated problem, it often relates to several interlinked issues:

1. Expansion Vessel Pressure: Some users have found the pressure in the expansion vessel to be low. Correcting this can be a temporary fix, but understanding the cause of the pressure drop is essential.
2. Automatic Air Bleed Valve (AAV) Issues: There were cases where limescale and other debris accumulated around the AAV. Cleaning it is essential, but if the valve shows signs of seepage, it can result in pressure loss.
3. Pressure Relief Pipework: Water dripping from the overflow or the pressure relief pipe is another symptom of this overarching problem.

Solutions:

1. Addressing the Automatic Air Bleed Valve (AAV): If there’s evidence of water seeping from the AAV, it might result in a loss of pressure. An immediate solution is to turn the black cap on the AAV clockwise until it’s finger-tight. This stops water loss temporarily. Ultimately, the AAV might need replacement.
2. Monitoring the Expansion Vessel: Regularly check the pressure in the expansion vessel. If it’s low, it might need to be pumped to the recommended levels. If the vessel loses pressure frequently, it indicates a bigger problem, and professional intervention might be necessary.
3. Checking Pressure Relief Pipework: Investigate the outdoor pressure relief pipework. If there’s water dripping or evidence of overflow, it means the pressure relief valve (PRV) is opening, which shouldn’t happen frequently. It’s vital to understand why the PRV is opening and address the root cause.
4. Recharging the Expansion Vessel (EV): To recharge the EV correctly, the system pressure should first be depressurized. If there’s water on the air side of the expansion vessel, it suggests potential issues, like a leaky PRV.
5. Draining the Boiler: If users suspect water in the air side of the expansion vessel, one can isolate the boiler from the system and drain that specific section. This can be a slightly technical task and might be best handled by a professional if users are unsure.

Conclusion:

While the Vaillant ecoTEC Plus 618 is a reliable boiler, occasional maintenance is key to its optimal functioning. Regularly inspecting different components, particularly the expansion vessel and the AAV, and addressing issues promptly can prevent more significant problems down the road. When in doubt, it’s always recommended to consult with a professional plumber or heating engineer.