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ecoTEC plus 400 series (2016 - Present)



The Vaillant ecoTEC plus 400 series are a range of high efficiency boilers that are not currently in production. Please check the frequently answered questions below for any help you may need. You can also click here to visit the appliance homepage.  




What kind of Appliance is it?

The ecoTEC plus 400 series are regular boilers. Regular boilers are also known as open vent boilers beause they are linked to an outside vent. The system provides central heating and hot water by using both a storage cylinder and water tank, which gives ultra-efficient operation. Due to the open vent they are not pressurised.

When was the boiler manufactured?

This boiler is a current boiler, was first manufactured in 2016 and is still in production.

Is there a clock or roomstat available?

A broad range of Vaillant thermostats and clocks are available. You can find technical help on these by typing in your model into the question bar above or by browsing through our homepage here.

What is the recommended water pressure?

This boiler is normally connected to system that has an open vent. This means these boilers are not pressurised. If your heating system has undergone a conversion and the water tank has been removed then this boiler may be pressurised. Please contact your Installer for more information on your system.

How do I top up the water pressure?

As this type of boiler is normally on a open vent system it is not pressurised so there is no need to top up the pressure. If your system has undergone a converson (see above), you will have an external filling loop and pressure gauge on your heating system. You can also find more information by downloading and checking the user manual as well as on our Youtube Channel.

My boiler has a fault and I need some help?

Your boiler should work reliably for a number of years if it is serviced annually, however occassionaly faults can occur. In a lot of cases faults can be temporary and if the boiler is reset it will start working again. You can find out how to do this by selecting the user manual below (under available literature). We have created a special troubleshooting guide which you can access by clicking here which may help you resolve the issue. If you continue to experience problems please click here for contact information.

I am an Engineer. I would like technical information. Where can I get help?

If you are a suitably qualified Gas Safe registered Engineer you can access our comprehensive technical help section by clicking here.


Available Literature


ecoTEC plus 400 series Installation Manual ecoTEC plus 400 series User Manual ecoTEC plus 400 Brochure

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