Single install and cascade flue systems

These flue components include concentric horizontal and vertical flues. The 80/125mm size is suitable for the ecoTEC plus 46 and 65kW vertical and horizontal terminals along with 87° and 45° elbows. For terminations requiring an outdoor run of flue pipe, Vaillant can supply a vertical facade flue system with the external components manufactured in stainless steel.

Whenever ecoTEC plus 46 and 65kW boilers are being fitted in any cascade formation, it is vital that a flue gas non-return flap/valve is fitted to each boiler to ensure that gas cannot re-enter the boiler. The only circumstances where a non-return flap is not necessary is if the chimney is designed to EN 13384-2 and the natural draught is greater than the pressure losses. Vaillant offers a mechanical 80mm flap valve for the ecoTEC plus 46 and 65kW models.

This range of Vaillant boilers utilises a 110/160mm concentric flue system for which we offer a number of flue system options that can be specified according to the requirements of the installation. Our standard concentric flue pipes can be purchased with a range of fittings to easily construct the appropriate flue system with horizontal or vertical terminations for your building. These comprise a 160mm outer air duct with a 110mm PP inner flue.

A variety of stainless steel facade flues can also be obtained to complement all flue system arrangements. Additional accessories including brackets, rain collars, sleeves and terminals are also available.

ecoTEC plus 80, 100 and 120kW models installed in a cascade array will need to be fitted with a flue non-return flap valve. Vaillant can supply a 110mm mechanical flue non-return flap valve or a 100mm shorter motorised one, which is easily installed on top of each boiler before connecting the flue header. When dealing with plant rooms with restricted heights, the Vaillant electrical flue non-return flap valve kit has a lower profile and can be specified in place of the mechanical flap valve, but these should not be mixed within an array.

For systems over 70kW, the current edition of the IGEM/UP10 guide should be followed and for larger systems over 333kW net, the Clean Air Act requirements and any local council approvals that may be required should be followed.