Vaillant elbow 87°, Ø 110/160 mm

Product detailed description

87° Elbow Vaillant, Ø 110/160 mm

The 87° directional elbow (commonly also referred to as a "90° elbow") is the most widely used directional component of the Vaillant concentric flue system Ø 110/160 mm. It enables the transition from a horizontal to a vertical duct run (or vice versa) – typically at the boiler outlet, which is connected horizontally, into a vertical shaft, or during the transition into a vertical roof outlet. The slightly deviated angle of 87° (instead of exactly 90°) is a deliberate design solution used by many flue system manufacturers, ensuring a slight natural slope for condensate drainage even at the point of directional change, preventing condensate accumulation in the elbow.

The component is connected using a bayonet lock with a seal at both ends and is fully compatible with all other parts of the Ø 110/160 mm range – extensions, inspection pieces, T-pieces and roof terminals.

Summary of technical parameters

• Part type: 87° elbow
• System diameter: Ø 110/160 mm (concentric)
• Directional angle: 87°
• Inner pipe material (flue gas): Polypropylene (PP), condensate resistance class W
• Outer casing material (air): UV-stabilized plastic
• Temperature class: T120
• Pressure class: P1
• Joint type: Bayonet lock with rubber seal, rotatable
• Intended for: ecoTEC plus VU 806/5-5 – 1206/5-5, ecoCRAFT exclusiv, ecoVIT exclusiv, cascade systems
• Country of origin: Germany / EU
• Brand: Vaillant
• Warranty: 24 months

Vaillant Ø 110/160 mm flue system

The pipe system with a diameter of Ø 110/160 mm belongs to the family of concentric (coaxial) flue systems by Vaillant designed for high-capacity gas condensing boilers with higher rated output – typically the ecoTEC plus VU 806/5-5, 1006/5-5 and 1206/5-5 range (output range approx. 80–120 kW), modular ecoCRAFT exclusiv and ecoVIT exclusiv systems, as well as cascade connections of multiple boilers to a common flue gas collector. The inner pipe, through which flue gases flow, is made of durable polypropylene (PP) with high temperature and chemical resistance to condensate (condensate resistance class W according to EN 14471), while the outer casing supplying combustion air is made of UV-stabilized plastic or aluminium depending on the specific component. The system is certified for temperature class T120, pressure class P1 (positive pressure system, suitable for condensing boilers) and corrosion class 1, which corresponds to the standard operating range of flue gases from condensing boilers (low-temperature flue gases, acidic condensates).

The Ø 110/160 mm system is installed exclusively using original Vaillant components – individual parts (extensions, elbows, inspection pieces, roof terminals and mounting elements) are combined into an assembly precisely according to the layout of the specific boiler room or plant room. All joints are sealed with a silicone seal using a bayonet lock system, which ensures gas-tightness even over longer pipe runs and allows for easy installation and disassembly without the need for gluing or welding.

Comparison with other diameters of Vaillant flue systems

Vaillant offers concentric flue systems in several diameters depending on boiler output – the smallest common diameter Ø 60/100 mm is used for most wall-mounted condensing boilers for houses and apartments (ecoTEC pro/plus range up to approx. 35–65 kW), the Ø 80/125 mm diameter is used for higher-output boilers or longer duct runs where lower pressure loss is required. The Ø 110/160 mm diameter, to which this part belongs, is intended for the highest common output segment (ecoTEC plus 806/5-5 – 1206/5-5, ecoCRAFT exclusiv, ecoVIT exclusiv) and cascade systems, where a significantly larger volume of flue gases needs to be discharged. Parts of different diameters are not interchangeable – when ordering, it is therefore always necessary to verify the exact system diameter on your boiler or in the project documentation.

Compatibility with boiler models

The 87° elbow is one of the most frequently sold parts of the Ø 110/160 mm system, as almost every installation includes at least one transition from a horizontal run from the boiler to a vertical run towards the shaft or roof outlet. It is used with higher-output ecoTEC plus units, ecoCRAFT exclusiv, ecoVIT exclusiv, and cascade systems of multiple boilers.

Typical usage scenarios

The most common scenario is a direct connection to the boiler outlet, which for design reasons is horizontal, while the subsequent run must continue vertically upwards towards the shaft or roof outlet – the 87° elbow performs this directional change in a single part. Another common point of use is at the top of a vertical run just before entering the roof terminal, where it may be necessary to slightly adjust the direction according to the position of the roof penetration.

How to choose between a standard and an inspection 87° elbow

Choose a standard 87° elbow if you do not need inspection access at that point of the run and it is provided elsewhere (for example, by a separate inspection piece or T-elbow further along the run). If, on the other hand, you need inspection access directly at the point of directional change, for example at the entry to the shaft, choose an inspection 87° elbow with a built-in inspection cap instead of this component.

Installation and use

The 87° elbow is most often installed directly at the boiler outlet (change from horizontal to vertical direction) or at the point where the run transitions from a ceiling/wall into a shaft. During installation:

• the elbow is pushed with the bayonet lock all the way into the adjacent component (boiler, extension, inspection piece),
• before final locking, the part can be slightly rotated within the plane of the lock so that the resulting orientation matches the actual direction of the continuing run,
• if the run continues vertically after the elbow, a support element (support elbow or bracket) must be installed immediately after the elbow to transfer the weight of the vertical branch into the building structure,
• if the elbow is part of a run without direct access (e.g. in a suspended ceiling), we recommend leaving inspection access nearby via an adjacent inspection piece or T-piece.

Safety notices

Installation and connection of the condensing boiler's flue system must be carried out exclusively by an authorized and trained installation company with professional qualification for gas appliances. An incorrectly assembled or leaking flue duct can lead to the escape of flue gases (including carbon monoxide) into living spaces, posing a serious health risk. Use only original Vaillant parts of the corresponding diameter and certification – combining with parts from other manufacturers or of different diameters is not permitted and violates the CE certification conditions of the entire assembly as well as the boiler warranty. After any intervention on the run (part replacement, servicing, inspection), a leak-tightness check must be performed before the boiler is put back into operation.

Maintenance and care

We recommend inspecting the flue system at least once a year during regular boiler servicing – particularly the tightness of joints, the patency of condensate drainage (if part of the assembly), and the mechanical fastening throughout the run. The outer plastic parts (roof terminals, penetrations) should be visually inspected after the winter season for possible mechanical damage caused by ice or wind. The inside of the pipes does not accumulate deposits during normal operation in the same way as traditional solid-fuel chimneys, but the inspection elements in the assembly (inspection elbows, inspection pieces, T-pieces) serve precisely to allow a service technician to easily look inside the pipe during inspection and clean it if necessary, without having to disassemble the entire run.

For boilers with a longer flue run, we recommend keeping a simple service record of the date of the last leak-tightness check and the condition of the inspection openings – this will make it easier to plan future chimney sweep inspections and provide an overview in case of a warranty claim or property sale.

Why buy this part from Atria.sk

We offer exclusively original Vaillant parts with 100% compatibility with this brand's flue systems – no universal replacements of questionable quality that could compromise the gas-tightness of the entire assembly or void the boiler warranty. Goods are usually in stock or quickly available from the supplier, so the completion of a boiler room installation or a service intervention is not delayed by a single missing part. If you are unsure which exact part you need for your assembly, we will be happy to advise you by phone or email – simply provide the boiler model and the length of the flue run you need to bridge.

We usually process orders within one business day and ship items in stock immediately. If you are not sure which exact part your project requires (for example, when combining several lengths and elbows into one run), we will be happy to help you choose the correct assembly before ordering – simply send us a floor plan or a photo of the installation site along with the boiler model.

Frequently Asked Questions