Navien NCB300 28kW Combi Boiler, Std Flue & Adey Micro 1 Filter

Description

The Navien NCB300-28K is a wall-hung, room-sealed gas condensing combi boiler rated at 28kW, supplied here complete with the Navien 1000mm Standard Horizontal Flue Kit (GXXX002208) and an Adey MagnaClean Micro 1 Filter (FL1-03-07129). Navien's entry-level combi model shares its core componentry with the larger NCB300/500/700 range, including dual stainless steel heat exchangers for long-term durability and a 6:1 turndown ratio for smooth modulation. The bundled Adey filter protects the boiler's heat exchangers from circulating magnetite and debris from day one, supporting the boiler's 5-year parts and labour warranty.

28kW

DHW Output

93%

ErP Efficiency (A)

11.5 l/min

DHW Flow (ΔT35°C)

6:1

Modulation Ratio

5 yrs

Parts & Labour Warranty

29kg

Lift Weight

Gas Safe Registration Required

Installation, commissioning and servicing of this boiler must be carried out by a Gas Safe registered engineer. The horizontal flue must be positioned in accordance with the clearances set out in the manufacturer's installation and operation manual, and a Benchmark commissioning checklist must be completed and left with the end user.

Bundle Contents & LPG Conversion

This listing supplies three separate boxed items designed to be installed together: the NCB300-28K boiler (PNCB3000028L001), the 1000mm Standard Horizontal Flue Kit (GXXX002208), and the Adey MagnaClean Micro 1 Filter (FL1-03-07129, 22mm compression). The boiler is shipped ready to fire on natural gas; an LPG conversion kit is included in the boiler packaging for field conversion by a suitably qualified Gas Safe engineer, but is not fitted as standard.

Why This Bundle

Dual Stainless Steel Heat Exchangers

The primary and secondary heat exchangers are both stainless steel rather than aluminium, giving strong resistance to corrosion from acidic condensate and supporting long-term reliability over the boiler's working life.

6:1 Turndown Ratio

A wide 6:1 modulation range lets the burner idle down to a low minimum output on milder days, avoiding the short-cycling that wastes gas and wears components faster on boilers with a narrower turndown.

Hydrogen-Ready (20% Blend)

The NCB300 is tested and approved for use with up to a 20% hydrogen blend in the gas supply, helping future-proof the installation against the anticipated transition of the UK gas network.

ErP A+ with Smart Plus

Paired with a Navien Smart Plus wireless thermostat, the system efficiency rating rises from ErP A (93%) to ErP A+ (98%), thanks to weather forecasting and location-based heating adjustments.

Adey Micro 1 Filter Included

The bundled Adey MagnaClean Micro 1 is a compact 22mm in-line magnetic filter with 360° rotational valves for flexible installation, and full vent, drain and flush capability for straightforward servicing.

Compact, Lightweight Design

At 395 x 285 x 680mm and 29kg lift weight, the NCB300 is built for easy cupboard-fit installation in smaller properties, without sacrificing DHW performance.

Technical Specification

General
Boiler article number	PNCB3000028L001 (NCB300-28K)
Flue kit article number	GXXX002208 (1000mm Standard Horizontal Flue Kit, 60/100mm)
Filter article number	FL1-03-07129 (Adey MagnaClean Micro 1, 22mm)
Boiler type	Wall-hung, room-sealed, fan-assisted condensing combi (B23-C13-C33-C53-C83)
Fuel type	Natural gas (LPG conversion kit included, field conversion required)
Dimensions (W x D x H)	395 x 285 x 680 mm
Guarantee	5 years parts and labour
Heating Performance
Heat input range	4.3 – 24.7 kW
Heat output range (80/60°C)	4.2 – 24.0 kW
Modulation (max/min)	6:1
Domestic Hot Water
DHW heat input / output range	4.3 – 28.0 kW
DHW flow rate (ΔT = 25°C)	16.0 l/min
DHW flow rate (ΔT = 35°C)	11.5 l/min
DHW flow rate, kitchen tap (ΔT = 45°C)	9.0 l/min
DHW turndown ratio	7:1
Performance & Emissions
ErP efficiency	A (93%) — A+ (98%) with Smart Plus control
NOx classification	Class 6
IP rating	IPX4
Sound level	52 dBA
Lift weight	29 kg
Flue
Flue diameter	Coaxial 60/100mm
Max. horizontal coaxial flue length	8 m
Max. vertical coaxial flue length	8 m
Bundled flue kit length	1000mm

Frequently Asked Questions

Does this listing include the boiler, flue, and filter, or do I need to buy them separately?

All three items are included in this single listing: the NCB300-28K boiler (PNCB3000028L001), the GXXX002208 1000mm horizontal flue kit, and the FL1-03-07129 Adey MagnaClean Micro 1 filter.

Can I run this boiler on LPG?

An LPG conversion kit is included in the boiler's packaging as standard, but the boiler ships configured for natural gas. Conversion to LPG must be carried out by a Gas Safe registered engineer holding the appropriate LPG qualification, following the procedure in the service manual.

Why is a magnetic filter included with the boiler?

The Adey MagnaClean Micro 1 protects the boiler's stainless steel heat exchangers from circulating magnetite and debris in the heating system, reducing the risk of blockages and helping protect the manufacturer's warranty.

Is the 1000mm flue kit long enough for my installation?

The bundled kit provides a 1000mm length, suitable for a standard through-wall termination. Runs up to the 8m maximum horizontal length require additional Navien 60/100 extension and bend accessories, sold separately.

What is ErP A+ with Smart Plus, and is it included?

The Smart Plus wireless thermostat and WiFi receiver are sold separately and are not included in this bundle. Pairing one with this boiler raises the system's ErP rating from A (93%) to A+ (98%).

Can I install this boiler myself?

No. UK law requires that all gas boiler installation, commissioning and servicing work is carried out by a Gas Safe registered engineer.

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