Vaillant EcoTEC Pro Combi Boiler Cost with Installation

Vaillant’s entry point into the ecoTEC family, the Pro is a compact, reliable combi for small to medium homes that want German engineering without the premium price. It has a stainless steel heat exchanger, Quiet Mark certification, and was our pick for best combi boiler for after sales services and support.

The warranty starts at just 2 years though, if the installer is not an Vaillant Advance Installer, and that’s worth reading before you decide.

Here’s a breakdown of the specifications for the Vaillant EcoTEC Pro combi:

Vaillant EcoTEC Pro Combi Product Table
	Available outputs	24kW	28kW	30kW
	Type	Combi	Combi	Combi
	Fuel	Gas	Gas	Gas
	Condensing	Yes	Yes	Yes
	Efficiency rating (%)	93	93	93
	ErP	A	A	A
	LPG compatible	Yes	Yes	Yes
	Standard guarantee	2-to-7 years*
	Max output (kW)	24	28	30
	Flow rate (l/min)	9.6	11.1	12.3
	Mounting	Wall-mounted
	Dimensions (mm)	720 x 440 x 335
	Typical price (incl. VAT)	£900	£1,050	£1,150
	Typical installation cost (incl. VAT)	£800 – £1,400
	Total cost	£1,700 – £2,550

*Terms and conditions apply.

Vaillant EcoTEC Pro Combi overview

The ecoTEC Pro stands out on three things: a patented stainless steel heat exchanger, aquaCOMFORT fast hot water delivery, and a low NOx burner with full modulation – features built to keep the boiler performing well a decade from now. 

It’s also hand-built at Vaillant’s Derbyshire plant, and compatible with the aroTHERM plus heat pump, which puts it in a different conversation from most boilers at this price when it comes to future-proofing.

Vaillant EcoTEC Pro Combi Range
Model output size	House size	Bathrooms	Radiators
24kW	Flats 1 to 2 bedrooms	1	Up to 8
28kW	Small homes 2 to 3 bedrooms	1	Up to 10
30kW	Small-medium homes 3 bedrooms	1-2	Up to 15

The Vaillant EcoTEC Pro combi is a capable performer across the range, but make sure to match the kW output to your home’s specific hot water demands! With hot water flow rates ranging from 10.2 to 15 litres per minute, the Vaillant EcoTEC Pro combi is well-suited to homes with one to two bathrooms. 

The 24kW handles single-bathroom homes comfortably, whilst the 30kW and 36kW models can manage two bathrooms – though in the morning rush, with multiple showers running simultaneously, you might notice a slight drop in pressure.

Key benefits at a glance

• ErP A-rated efficiency (93%)
• Stainless steel heat exchanger
• Low NOx burner with full modulation
• aquaCOMFORT warm start (hot water faster from cold)
• Quiet Mark certified (28kW and 30kW)
• Compact at 720mm high, fits standard cupboards
• Compatible with Vaillant smart controls and vSMART app
• Compatible with aroTHERM plus heat pump for future hybrid upgrade
• LPG compatible
• 2-year standard guarantee, free 7-year warranty extendable to 10 years*

Vaillant EcoTEC Pro Combi technical specifications

The Pro sits in a specific part of the Vaillant range: above the entry-level ecoFIT pure on build quality, with the stainless steel heat exchanger and aquaCOMFORT, but without the Exclusive’s Green iQ optimisation and Extra-Condense technology. The result is a boiler that costs considerably less while sharing the core components that determine longevity.

Output and efficiency ratings

All three models have a 93% efficiency and an ErP A-rating. Hot water flow rates run from 9.6 l/min at 24kW to 12.3 l/min at 30kW, this is adequate for single bathroom use and light two-bathroom use.

The modulation ratios vary slightly across the range: the 28kW is the widest at 1:5, while the 30kW sits at 1:3.8 and the 24kW at 1:4.3. All three are narrower than most premium rivals (the Viessmann 200-W modulates to 1:17, the Vaillant ecoTEC Exclusive to 1:10) which means the Pro cycles on and off more frequently in low-demand periods. It’s not a problem in everyday use, but it’s part of what separates this boiler from the models above it in Vaillant’s own range.

Dimensions 

Like many of the combis on the market, the Vaillant EcoTEC Pro is compact and cupboard-friendly. All three output sizes share the same footprint: 720mm high, 440mm wide, 335mm deep. That 335mm depth beats most rivals which have deeper dimensions, and in a kitchen cupboard that extra space can be the difference between fitting cleanly and not fitting at all.

Components included

Stainless steel comes as standard even at the entry level of this range, which is not something you can say about the Worcester Bosch Greenstar 4000 or the Ideal Logic+. In hard water areas, aluminium heat exchangers scale up faster and corrode sooner. If you’re installing a boiler and planning to stay in the house for a decade or more, the material your heat exchanger is made of matters more than almost any other spec on the sheet.

Also included is the aquaCOMFORT – Vaillant’s warm start feature keeps a small amount of warm water ready in the heat exchanger, so hot water arrives at the tap faster than a boiler starting entirely from cold. It uses a small amount of additional energy to maintain that warm state, but the practical effect is noticeable.

There is no built-in WiFi, but the ecoTEC Pro is designed to work with Vaillant’s range of optional smart controls. Smart controls compatible with the Pro include the sensoROOM, sensoCOMFORT, or vSMART, but none of them are included in the box. If smart heating control matters to you, factor in an additional £100-£200 for a compatible thermostat. The boiler’s own display is a simple, clear LCD, bright and functional, no touchscreen.

One feature that’s easy to overlook: the ecoTEC Pro is compatible with Vaillant’s aroTHERM plus air-to-water heat pump as a hybrid system. This matters for homeowners thinking about future-proofing. If you’re installing a new boiler now but want the option to add a heat pump later without replacing the boiler entirely, the Pro is set up for exactly that transition.

Prices and installation costs

This price usually includes the boiler unit and standard horizontal flue.

The flue is a critical component that safely directs combustion gases outside your home; whilst a standard side-wall flue costs roughly £100, a vertical roof flue can exceed £500 due to the increased complexity of the installation and roofing work required.

Ultimately the standard installation cost is around £1,200, which is the price we’ve used in our cost breakdown.

At this price point the ecoTEC Pro competes against the Ideal Logic+ and the Worcester Bosch Greenstar 4000 rather than premium models. 

Vaillant EcoTEC Pro Combi Costs
Output size	Unit cost (incl. flue)	Total (incl. installation)
24kW	£900	£2,100
28kW	£1,050	£2,250
30kW	£1,150	£2,350

Warranty and support

The standard warranty is 2 years, the shortest of any boiler we’ve seen so far. Two years is a legal minimum, and by comparison the Worcester Bosch Greenstar 8000+ starts at 8 years standard, the Viessmann 200-W at 10.

A Vaillant Advance installer can register the boiler for a free 7-year warranty, there’s no charge for this, it simply requires using a registered engineer and completing the registration. The full 10-year warranty is available for an additional £150 + VAT, payable at the time of installation. Both require annual servicing with the Benchmark checklist completed.

The 7-year warranty is fairly easy to activate, which means the realistic question is: is it worth paying £150 for an extra 3 years on top of the free 7? In most cases, the answer is yes.

Installation information

A standard installation typically costs around £1,200. 

The ecoTEC Pro is well liked by installers: all components are accessible from the front; the side panels are removable for wider access; and Vaillant have designed it with straightforward commissioning in mind. 

A like-for-like swap will sit at the lower end of the cost range.

What to expect on installation day

Do you need a system flush or filter?

Yes, under UK Building Regulations, it is now a mandatory requirement to fit a magnetic filter when installing a new boiler. A system flush isn’t legally required, but it’s strongly recommended if you’re replacing an older boiler, and many manufacturers (including Vaillant) make it a condition of their extended warranty.

A flush removes sludge (iron oxide and other debris) that has built up over the years in your radiators and pipework.

Whilst both options offer excellent protection for your heating system, they do involve extra costs. As a guide, a system flush typically costs between £350 and £800, and a filter between £65 and £300, depending on your setup.

Finding a Gas Safe registered engineer

All installations must be carried out by a Gas Safe registered engineer. 

For the ecoTEC Pro specifically, the warranty tier your installer belongs to directly determines how long you’re covered for, which makes the choice of engineer more consequential here than with most boilers. 

Use the WhatPrice quote service to be matched with vetted, Gas Safe registered installers in your area.

Reviews and ratings

Vaillant holds a rating of 4.5 out of 5 stars on Trustpilot in the UK. With over 22,900 reviews, their score reflects a very high level of consistent quality across their product range.

Positive reviews

The clearest theme across positive reviews is repeat purchasing driven by long-term reliability. Several customers are on their second or third ecoTEC Pro after previous units ran for over 10 years without significant problems. One reviewer replacing a Pro 28 after 11 fault-free years described the upgrade decision as straightforward, and another buying again after a house move said the choice of boiler needed no deliberation whatsoever.

Quiet operation comes up consistently, with reviewers noting it as an immediate and welcome contrast to the boilers being replaced. Efficiency gains are also mentioned, including one customer reporting savings of around £10 in the first week after switching from an old back boiler, and another describing an instant improvement in how quickly and evenly the house heated up.

The seven or ten-year warranty features as a purchasing factor, with several reviewers citing it alongside the brand’s reliability track record as the reason for sticking with Vaillant over competitors.

Negative reviews

Hot water performance is the most significant complaint. One owner of the Pro 28 describes having to run around 20 litres of water before it reaches a usable temperature, and when they paid £98 for a Vaillant engineer to investigate, they were told the boiler was functioning as designed. Despite follow-up contact, Vaillant maintained that position, which the customer found unacceptable, though Vaillant did subsequently waive the £98 charge.

Warranty support has clear practical limits that catch some customers off guard. When a pump failed on a Saturday in freezing conditions, one customer with two ecoTEC Pro boilers found Vaillant unable to attend for several days and unwilling to pre-authorise a third-party repair. After the customer arranged and funded their own fix, Vaillant declined to reimburse the cost on the grounds that a non-Vaillant engineer had carried out the work – a condition that had not been clearly communicated.

A condensate pooling issue inside the boiler casing is flagged by one Pro 30 reviewer, who notes that Vaillant are aware of the problem across the current batch but have yet to identify the cause. One further reviewer reports a low-frequency droning noise during hot water demand on a Pro 28 that is audible throughout the house, which Vaillant confirmed is within normal operating parameters, which is an answer the customer found unsatisfactory

How the Vaillant EcoTEC Pro Combi compares

Vaillant EcoTEC Pro Combi Comparison Table
Model	Vaillant EcoTEC Pro Combi	Worcester Bosch Greenstar 4000 Combi	Ideal Logic+ Combi
Typical unit price	£1,050	£1,200	£1,000
Heat exchanger	Stainless steel	Aluminium	Aluminium
Standard warranty	2 years	7 Years	7 Years
Max warranty	10 years	10 Years	10 Years
Built-in WiFi	No	Yes	No
App control	vSMART	Bosch EasyControl	Ideal Halo
Cupboard fit	Yes	Yes	Yes
Max output/bathrooms	30kW 1-2 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 Vaillant EcoTEC Pro Combi right for you?

The ecoTEC Pro is harder to sum up than most boilers because the right answer depends heavily on which warranty you actually end up with.

At 2 years standard, it’s a weaker safety net than the Worcester Bosch Greenstar 4000 – which starts at 7 years for roughly the same money. If your installer can unlock the 7-year Vaillant Advance route without extra charges, the comparison closes significantly; if they can’t, the Worcester is the simpler choice. That said, the Pro has a stainless steel heat exchanger where the 4000 uses aluminium, and for anyone in a hard water area who plans to keep the boiler for ten years or more, that’s not a minor footnote.

Against the Ideal Logic+, the Pro costs only slightly more but the stainless steel and Vaillant’s reliability record justify the gap. 

Where the ecoTEC Pro makes the most sense is for homeowners who want a compact, reliable boiler at a mid-range price, who understand that getting the most from the warranty means choosing the right installer, and whose home doesn’t need more than the 30kW ceiling. Add the hybrid compatibility with the aroTHERM plus and there’s also a future-proofing argument here that the Worcester 4000 and Ideal Logic+ can’t match – if you’re thinking about a heat pump in five years’ time, the Pro is already set up for it.

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