Alpha E-Tec NX Combi Boiler Cost with Installation

So, you’re looking for a new combi boiler? Well – if it’s affordability and reassurance you’re after, then this is the right page for you. The Alpha E-Tec NX was voted our best combi boiler for price and warranty length, being the cheapest combi in our top 10! You’re getting an incredible 9-year maximum warranty for a boiler that has a lot to offer – from a stainless steel heat exchanger for durability to smart control compatibility for personal control. 

Let’s take a closer look at the Alpha E-Tec NX specifications below:

Alpha E-Tec NX Combi Product Table
	Available outputs	28kW	33kW
	Type	Combi	Combi
	Fuel	Gas	Gas
	Condensing	Yes	Yes
	Efficiency rating (%)	94	94
	ErP	A	A
	LPG compatible	Yes	Yes
	Standard guarantee	7 years*
	Max output (kW)	28	33
	Flow rate (l/min)	12.1	14.1
	Mounting	Wall-mounted
	Dimensions (mm)	712 x 440 x 255
	Typical price (incl. VAT)	£800	£900
	Typical installation cost (incl. VAT)	£700 – £1,200
	Total cost	£1,500 – £2,100

*Terms and conditions apply.

Alpha E-Tec NX combi overview

The Alpha E-Tec NX comes in two output sizes – 28kW and 33kW – offering choice for homeowners with differing hot water demands.

The E-Tec NX combi is built with high-quality internal components, designed to deliver dependable hot water performance. However, choosing the right output size can really make or break the performance of your boiler. 

Alpha E-Tec NX Combi Range
Model output size	House size	Bathrooms	Radiators
28kW	Flats, small homes 1 to 3 bedrooms	1	Up to 10
33kW	Small-medium homes 3 to 4 bedrooms	1 & ensuite	Up to 15

It’s essential that you choose the right output size for your home. The 28kW model is recommended for smaller homes with one bathroom and less hot water demand, whilst the 33kW model can accommodate slightly greater hot water usage. 

It’s important to note that bigger isn’t always better – having a greater output size in a home that doesn’t need it won’t improve hot water flow. In fact, it can run less efficiently and cost you more in the long run.

If your home has greater hot water demand – particularly simultaneous hot water usage – and you’re interested in an Alpha combi then it might be worth checking out the Alpha E-Tec Plus NX, which offers models with an output up to 38kW and has a few more premium features and a longer standard warranty.

Key benefits at a glance

• ErP A-rated efficiency (94%)
• Smart Control via Alpha Connect app
• Stainless steel heat exchanger
• Wide modulation range (1:6)
• Compact, cupboard-friendly design
• Quiet operation (48dB) 
• Built-in frost protection
• Weather compensation control compatible
• LPG compatible
• 7-year standard warranty, extendable to 9 years*

*The PremierPack Pro adds an additional 2 years to the E-Tec NX.

Alpha E-Tec NX combi technical specifications

Built with high-quality internal components, the Alpha E-Tec NX combi is well-protected to offer you peace of mind. And with smart controls, a wide modulation range, and weather compensation compatibility, your boiler can be adjusted to avoid using excessive energy when it isn’t needed.

Output and efficiency ratings

Offering two outputs – 28kW and 33kW – the Alpha E-Tec NX combi is ideal for smaller homes with moderate hot water usage. 

The Alpha E-Tec NX offers A-rated efficiency, running at 94% efficiency. Essentially, your boiler will minimise fuel wastage, particularly compared to older, non-condensing boilers running at just 60-70% efficiency. This is invaluable in reducing long-term running costs and your carbon footprint.

With a modulation range of 1:6, this clever little combi can also reduce output to as low as 5kW during periods of low demand to avoid unnecessary energy waste.

Dimensions 

As a combination boiler, the Alpha E-Tec NX avoids the need for a separate hot water cylinder and storage tank by providing central heating and hot water directly from the mains. This keeps the boiler compact and with dimensions of 712 x 440 x 255, the E-Tec NX is the ideal compact boiler for installation in a standard kitchen cupboard or sitting discreetly in your chosen spot without being a bulky eyesore.

Components included

The real star of the show in the Alpha E-Tec NX combi is its stainless steel heat exchanger. This is a far more durable design choice than the aluminium heat exchangers in other combi boilers, preventing corrosion and enhancing durability.

If you value control over your heating system, you’ll be reassured to find that the E-Tec NX combi is compatible with the Alpha Connect app and other smart thermostats such as Nest and Hive. Alpha Connect allows users to make heating adjustments and set geolocation fencing – saving energy when no one is home.

With built-in frost protection, your boiler is also safeguarded against changeable and damaging weather conditions. This is particularly useful if your boiler is installed in a cold garage space or your house is left unoccupied. Compatible with weather compensation controls, the Alpha E-Tec NX can also adjust water flow depending on outside conditions – lowering it when the weather is warmer, and saving you money on your energy bills.

Prices and installation costs

Priced at £800 for the 28kW model and £900 for the 33kW model, the Alpha E-Tec NX combi is an affordable combi especially when considering its standout warranty.

Our prices include the boiler unit as well as a standard horizontal flue. A flue is a critical component that funnels waste gases outside. Whilst a standard horizontal flue costs around £100, a vertical flue that exits via the roof can cost up to £500 due to the complexity of installation and roofing work needed.

We’ve used a typical installation cost of £1,200 in our pricing. However, it’s important to bear in mind that installation costs can vary widely depending on your existing heating system and the complexity of work needed fitting the flue.

Alpha E-Tec NX Combi Costs
Output size	Unit cost (incl. flue)	Total (incl. installation)
28kW	£800	£2,000
33kW	£900	£2,100

These prices are only indicative, based on our research and actual boiler prices submitted to WhatPrice by homeowners.

To get an accurate price based on your needs, you should request quotes from at least three Gas Safe registered installers. They can advise you on the best boiler type for your home and give you tailored estimates to compare. 

Alternatively, you can use the WhatPrice Boiler Cost Calculator to get a guide price for your installation.

Warranty and support

With a 7-year standard warranty on parts and labour, the Alpha E-Tec NX is well-protected against any potential failings. This warranty can be extended by 2 years, to an incredible 9 years, if installed with the Alpha PremierPack Pro.

What is the PremierPack Pro, you ask? It is Alpha’s wall-mounting jig that includes a Cyclone magnetic filter. This filter removes metallic debris from the system to prevent damage to internal parts. 

To unlock and maintain the standard and maximum coverage, the boiler must be registered within 30 days of installation and receive an annual service by a Gas Safe registered engineer, and to be able to provide proof of past servicing if anything does go wrong. Unless it is not possible, you will likely need to have a system ‘flush’ when installing your new Alpha combi – not cleaning the system can invalidate the warranty. 

This warranty provides comprehensive protection against manufacturing defects or faulty materials; it does not cover damage caused by external factors such as hard water scale, internal system corrosion from poor water quality, or faults in the external gas and electricity supplies.

Installation information

An installation for the Alpha E-Tec NX is typically around £1,200. However, this can be variable depending on the complexity of work needed.

This model is designed with a removable push fit flue connection which allows for quick installation of vertical or horizontal flue configurations – making installation day just that bit easier.

What to expect on installation day

If additional work is required – such as upgrading pipework or relocating the boiler – your installer should explain this clearly beforehand, including any impact on cost or installation time.

Do you need a system flush or filter?

Under UK Building Regulations, it is now mandatory to fit a filter when installing a new boiler. A flush isn’t necessary, and can be an excessive cost, but your engineer may recommend it depending on the condition of your existing heating system. Under Alpha’s warranty terms, it could invalidate the long warranty if your heating system needs to be flushed and isn’t.

A magnetic system filter is fitted to the heating system to capture debris before it can circulate through the boiler. This is imperative to protecting internal components – particularly the heat exchanger – and supports long-term reliability.

A system flush is usually carried out before the new boiler is installed. It uses a specialist cleaning solution to remove sludge, rust, and debris from radiators and pipework. This helps improve heat circulation, ensures radiators warm evenly, and reduces the risk of blockages that could affect boiler performance.

Typically, a system flush will cost between £350 and £800, whilst a magnetic system filter can cost anywhere from £65 to £300.

Finding a Gas Safe registered engineer

It is a legal requirement that a Gas Safe registered engineer installs your gas boiler. This ensures work meets safety regulations and is completed to the best standard,

This is particularly essential if you want to activate that long warranty that Alpha has to offer – having a Gas Safe installer is one of the requirements of unlocking the 7-9-year warranty.

It’s always best to gather quotes from several Gas Safe registered engineers before choosing an installer. This allows you to compare pricing, experience, and recommendations.

Reviews and ratings

Alpha has an Excellent Trustpilot score, with 4.7 out of 5 stars. Considering Alpha is a slightly smaller company compared to major competitors like Worcester Bosch and Viessmann, such high praise from homeowners is a confident indicator of the quality and reliability of Alpha boilers.

Positive reviews

Many users who chose the NX over the Plus noted that for a lower price, they still got the stainless steel heat exchanger, which is usually only found in premium brands. 

Residents in flats or small houses frequently praise the 28kW model for its ability to heat up radiators almost instantly despite its compact size. There are also frequent remarks that the 28kW model is incredibly quiet in the kitchen.

For the 33kW model, reviewers praise the powerful shower pressure, often comparing it favourably to more expensive Worcester or Baxi models they had previously.

Negative reviews

Some negative feedback mentions the flow sensor sticking within the first year. Whilst fixed under warranty, users noted that intermittent lukewarm water was a frustrating early issue.

A common complaint among NX owners is that the Alpha helpline can have long wait times, sometimes over 30 minutes, particularly during the winter months.

Several users reported having to top up the pressure more frequently than they expected. This is often a system issue, but users tend to blame the boiler unit itself.

How the Alpha E-Tec NX combi compares

There are a range of competitors to consider before deciding on which boiler is best for you. Weighing up warranty, cost, internal components, additional smart controls, and output size can be tough. To make it a bit simpler, we’ve compared the key feature of Alpha E-Tec NX and its closest competitors – combi boiler models that are designed for similarly sized homes.

Alpha E-Tec NX Combi Comparison Table
Model	Alpha E-Tec NX Combi	Worcester Bosch Greenstar 4000 Combi	Viessmann Vitodens 050-W Combi
Typical unit price	£850	£1,200	£1,150
Heat exchanger	Stainless steel	Aluminium	Stainless steel
Standard warranty	7 Years	5 Years	7 Years
Max warranty	9 Years	10 Years	10 Years
Built-in WiFi	Optional extra	Yes	Yes
App control	Alpha Connect	Bosch EasyControl	ViCare
Cupboard fit	Yes (712mm high)	No (Slightly taller)	Yes (700mm high)
Max output/bathrooms	33kW 1 & ensuite bathrooms	30kW 1 & ensuite bathrooms	35kW 1-2 bathrooms

Keep in mind that this comparison focuses on key features, but there may be other details that matter more for your home. For personalised guidance on choosing the right boiler, we recommend speaking with a Gas Safe registered engineer.

Final thoughts – is the Alpha E-Tec NX combi right for you?

Looking at the Alpha E-Tec NX in the context of homeowner reviews, it becomes clear that this boiler is a great all-rounder: providing reliable, efficient heating and hot water for small to medium homes at a lower upfront cost than most mainstream rivals, without stripping back the core engineering.

Both the 28kW and 33kW models achieve A-rated efficiency at 94%, which is effectively on par with most modern condensing combi boilers from larger brands. This means gas consumption will be broadly similar to competitors such as the Worcester Greenstar 4000 or Viessmann Vitodens 050-W. The real differentiator is the stainless steel heat exchanger. At this price point, many competitors still use aluminium, which can be more sensitive to poor system water quality over time. Installers often view stainless steel as a durability advantage, particularly in older properties, and this is where the Viessmann Vitodens 050-W and Alpha E-Tec NX pull ahead of the competition.

Warranty is another factor that often makes the difference to homeowners. The E-Tec NX comes with a seven-year warranty as standard, which is already stronger than many entry-level combis. With the addition of Alpha’s PremierPack Pro and correct registration and servicing, this can be extended to nine years. Whilst this still falls slightly short of the ten or twelve years offered by Worcester or Viessmann, it is important to consider the price difference. The Alpha E-Tec NX combi often delivers a similar length of cover to rivals that cost significantly more to buy, which is why we score it highly for its value for money.

Considering smart controls, Viessmann places more emphasis on integrated controls and a personalised user experience, including app control as standard. The Alpha E-Tec NX can also allow for personal control, but via optional controls rather than built in as default. In return, the NX remains cheaper to buy and still matches up well on fundamentals such as efficiency, compact size, and heat exchanger material.

When comparing the Alpha E-Tec NX with a Worcester Bosch combi, the key difference is the strength of Worcester Bosch’s nationwide installer and servicing network. With a wide network of Gas Safe engineers across the UK – who have direct access to readily available spare parts and experience installing Worcester Bosch models – Worcester Bosch benefits from quicker diagnostics and easier access to servicing over the life of the boiler, which some homeowners find reassuring. The Alpha E-Tec NX, whilst generally straightforward to install and maintain, does not have the same scale of installer coverage, and this is often why Worcester Bosch models are recommended as the safe option despite their higher upfront cost.

When it comes down to it – your decision should consider your priorities. The Alpha E-Tec NX combi is an efficient, well-built combi for modest hot water demand, priced below most competitors but still offering durable components and a reassuring warranty. It is less well suited to homes with high simultaneous hot water usage or buyers who prioritise installer networks and built-in smart features above cost. For homeowners who want a balance between specification, performance, and price, the E-Tec NX remains a great choice.

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