SPECIAL OFFERS
Vaillant 303800 Vertical Flue Kit
Vaillant 303800 vertical flue kit for routing flue gases vertically from a compatible Vaillant boiler installation.
£144.00
£120.00 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Vaillant 303800 is a vertical flue kit for Vaillant boilers. It forms the vertical flue route that carries combustion products away from the appliance to the outside, as required by the boiler installation instructions. It is supplied as a kit rather than a single flue component.
Signs this part needs replacing
- Visible corrosion, pitting or perforation on the flue terminal or flue pipework
- Deformation, impact damage or cracking to the flue sections
- Staining, damp patches or condensate tracking around flue joints
- Perished or degraded seals and gaskets at the flue connections
- Flue-related fault codes or repeated boiler lockouts traced to the flue system
Before you order
- Confirm against the appliance installation instructions that a vertical flue route is the correct arrangement for the boiler
- Check the existing flue configuration and terminal position so the replacement matches what is already installed
- Verify the part number 303800 against the part number quoted for your appliance before ordering
- Check that all existing flue joints and seals will be accessible for the replacement work
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| SPECIAL OFFERS VAILLANT SALES ITEMS | — | — | — | |
| SPECIAL OFFERS Vaillant Sales Items | — | — | — |
Documents & drawings
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No documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
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