Internal Fitting Seal for Gas Boiler Flue Installation

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Solution Overview

Problem

Existing combustion appliance installations, particularly gas boilers, are time-consuming and require multiple personnel due to safety requirements, necessitating external modifications and complex sealing procedures that damage the building structure.

Innovation Solution

A one-piece, deformable internal fitting seal with a main body, comprising a front section, rear section, and fixing section, allowing installation from the interior of the property, eliminating the need for external access and reducing the number of personnel required.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional sealing assemblies are used for combustion appliance installation, then safety requirements are met, but installation time increases and multiple personnel are required

Engineering Contradiction:
ImprovesafetyVSAvoidinstallation time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The sealing assembly is divided into distinct functional sections: a front section with a covering flange for external sealing, a rear section with sealing lips for internal sealing, and a fixing section with openings for mechanical attachment. This segmentation allows each section to perform its specific function efficiently while enabling single-person installation from the interior.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention inverts the traditional installation approach by enabling installation from the interior of the property rather than requiring external access. The fixing section with openings allows the seal to be mechanically attached to the flue from inside, reversing the conventional exterior-to-interior installation method and eliminating the need for multiple personnel and external modifications.

Inventive Principle:
Principle #13The other way round (Inversion)

2Reliability

If traditional sealing procedures are used, then environmental seal is achieved, but building structure is damaged

Engineering Contradiction:
Improveenvironmental sealVSAvoidbuilding structure integrity
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The seal is pre-assembled with the flue assembly before installation, with the fixing section already positioned to receive fasteners through the openings. This preliminary preparation ensures that the environmental seal is created without requiring subsequent external modifications or repairs to the building structure.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The covering flange acts as an intermediary element that provides the external sealing function without requiring modification of the building's exterior bricks or structure. The flange interfaces with the wall opening while protecting the internal sealing lips, mediating between the internal seal and external environment without damaging the building structure.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Reliability

If multiple personnel are hired for installation, then safety requirements are fulfilled, but installation cost increases

Engineering Contradiction:
ImprovesafetyVSAvoidinstallation cost
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The sealing assembly is designed to be self-installing from the interior by a single person. The fixing section with openings enables the installer to mechanically attach the seal to the flue using fasteners passed through the openings, eliminating the need for external assistance or specialized personnel. The design inherently provides the means for its own installation while maintaining safety standards.

Inventive Principle:
Principle #25Self-service

4Reliability

If external access is required for sealing installation, then proper sealing is achieved, but installation complexity increases

Engineering Contradiction:
Improvesealing qualityVSAvoidinstallation complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention merges the external covering flange and internal sealing lips into a single integrated sealing assembly that attaches to the flue from the interior. This combination eliminates the need for separate external and internal sealing components, simplifying the installation process while maintaining both external aesthetic sealing and internal environmental sealing functions.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The sealing assembly performs multiple functions simultaneously: the covering flange provides external sealing and aesthetic coverage, the sealing lips create the environmental seal, and the fixing section enables mechanical attachment. This multi-functionality allows a single component to replace multiple separate elements, reducing installation complexity while achieving comprehensive sealing.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Facilitates quick and cost-effective installation of a combustion appliance by a single person, ensuring a safe and effective environmental seal without damaging the building structure.

Implementation Method 1

the main body can be configured so that it can deform when the seal is pushed through a hole of a wall which has a slightly smaller dimension, in particular cross section, than the seal

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Data Source

PatentEP4377611B1Internal fitting seal
Publication Date: 2025.11.19 BDR THERMEA GRP
  • EP4377611B1 patent drawingFigure 1
  • EP4377611B1 patent drawingFigure 2
  • EP4377611B1 patent drawingFigure 3

AI summary

Seal (1), in particular an internal fitting seal, fixable to a flue (2) of a combustion appliance (3), in particular a gas boiler, the seal (1) having a main body (4) comprising a front section (5) comprising a covering flange (6), a rear section (7) comprising at least a sealing lip (8), and a fixing section (9) located between the front section (5) and the rear section (7), wherein the fixing section (9) comprises fixing means (10) used for fixing the seal (1) to an external surface (11) of the flue (2) of the combustion appliance (3).