Storage Combi Boilers

If you’re struggling to understand the difference between combi and storage boilers or want to know more about combi storage boilers in general, we’ve written this article to help you.
Read on to investigate the ins and outs of storage combi boilers and how they can help you heat your home economically and with a minimal environmental impact.
In this article on storage combi boilers, we’ll cover:
- what a storage combi boiler is,
- the pros and cons of storage combi boilers,
- who might benefit from a storage combi boiler,
- different storage combi boiler options available in the UK today,
- the HomeSage top 5 storage combi boilers complete with mini reviews.
We’re HomeSage – we’ve scored the top five storage combi boiler ranges available in the UK marketplace today to give you a more in-depth understanding of their features, functionally, and price points.
We can save you hundreds of pounds on your storage combi installation.
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What is a storage combi boiler?
As you know, a standard combi boiler draws cold water directly from the mains supply.
It then heats up that water on demand inside the unit to provide you with an endless stream of hot water.
A storage combi boiler is similar in that it does use water from the mains but also has the capacity to store hot water within its own internal cylinder.
This makes them a little bit like a system boiler but, generally speaking, they are nowhere near as big – meaning a small flat or house will have room for a storage combi boiler.
Storage combi boilers are great because you have the option of a wall-hung or floor standing unit.
Whichever you choose, your storage boiler provides good hot water pressure even if more than one person is using the hot tap at one time.
This means no more arguments in your household when someone wants hot water from the kitchen tap while you’re having your morning shower.
Storage combi boilers pros and cons
Because we are an impartial website and like to give our readers a balanced overview of their options, here we have listed the benefits and disadvantages of storage combi boilers.
Storage combi boiler advantages
- They meet high demands for hot water and heating – if you like the sound of a combi boiler but your household has a high demand for hot water, a storage combi boiler could be the answer you’re looking for.
- They house a hot water cylinder within the unit – so you don’t need extra loft or garage space for an external water tank but you can still reap the benefits of excellent high hot water pressure that is available 24/7.
- Multiple outlets benefit from the hot water at one time – both the central heating and numerous hot taps can be used at once by members of the household.
There’s no drop in water pressure or temperature meaning that they are perfect for properties with more than one bathroom.
- They are cheaper than system boiler systems – generally speaking, storage combi boilers cost less to purchase and install.
That’s because there is less pipework required and because the system itself is generally smaller.
- They are compatible with solar thermal options – for an even smaller carbon footprint, consider installing solar panels to link with your storage combi boiler.
This is an option that isn’t available with a conventional combi boiler and means you are saving more money and the environment.
Storage combi boiler disadvantages
- They are usually more expensive than combi boilers – because they have the added feature of the internal storage cylinder, storage combi boilers are usually more expensive than standard combi boilers.
However, you are getting more for your money but you need to be sure in yourself that the increased price can be justified.
- They are bigger than combi boilers – similarly, because there is more technology involved, they are larger in size than a normal combi boiler.
Depending on the model you choose, they can either be wall-hung or floor standing but may take up a little more room so it’s worth measuring different locations around your home to see where it will fit best.
- The cylinder size determines the capacity of the boiler – each model varies so you need to consider how much water you are likely to see at one time.
It’s also important to be aware of how long it may take for the cylinder to refill with hot water (this usually isn’t a big issue and can be done in as little as 5 minutes).
Should you choose a storage combi boiler?
Deciding on the best central heating option for your property is important as it’s an investment for the future.
Storage combi boilers are a solid choice for properties with 1 to 2 bathrooms and a higher than usual demand for hot water.
Often, people choose a storage combi boiler if they initially wanted a system boiler but they don’t have enough room for the hot water storage tank.
A storage combi boiler might be the answer for those looking for a new heating system in a property which is short on space.
You will need to have a slightly larger budget as these types of boilers can be a few hundred pounds more than the straightforward combi boiler option.
Storage combi boilers you can choose from
There are 12 storage combi boiler models available to purchase in the UK at time of writing from three manufacturers and with an average price tag of £1,989 not including installation or extras.
There are three models from Viessmann with seven variants, one model from Vaillant with four variants, and one model from Glow-worm.
Here at HomeSage we want to help our readers make a savvy boiler purchase with as much information as possible, so we developed our own 100% unique boiler rating system to show you specifications at a glance.
Our online boiler scoring system takes the following into account:
- boiler output,
- energy efficiency rating,
- price point, and
- genuine customer reviews and ratings on Trustpilot.
This way, you can be sure you’re getting the storage combi boiler that will suit your property needs as well as your budget.
1st place – Glow-worm Energy 35 Store Boiler
Make | Glow-worm |
Model Name | Energy 35 Store 35 Boiler |
Type | Storage combi |
Power | Gas |
Location | Internal |
Condensing? | Condensing |
Efficiency Rating | 89.40% |
Band Rating | B |
LPG Compatible? | Yes |
Parts and Labour Warranty in months | 84 |
Heat Exchange Warranty in months | 84 |
Output kW | 35 |
Mounting | Wall Mounted |
Flow Rate | 14.4 |
Price from | £1,550 |
Price to | £1,610 |
ERP Heat | A |
ERP Water | A |
TOTAL | 81.20% |
The winner of the best storage combi boiler according to the exclusive HomeSage rating system is the Glow-worm Energy 35 Store boiler.
With an output of 35kw, this is ideally suited to larger semi-detached or detached properties.
With prices from around £1,550, it’s also more than £400 cheaper than the average-priced storage combi boiler on the market.
Containing two insulated tanks housed within the boiler itself, the water reheat time is just five minutes.
Size-wise, the boiler is 890mm x 470mm x 561mm – much larger than standard combi boilers but still remarkably small considering what’s contained behind the panel.
The boiler comes with a 2-year warranty as standard however you can increase that to 15 years if you choose to have it installed by a Glow-worm Club Energy installation firm.
2nd place – Vaillant ecoTEC plus Storage Boiler
Make | Vaillant | Vaillant | Vaillant | Vaillant |
Model Name | ecoTEC plus 825 Boiler | ecoTEC plus 832 Boiler | ecoTEC plus 835 Boiler | ecoTEC plus 838 Boiler |
Type | Storage combi | Storage combi | Storage combi | Storage combi |
Power | Gas | Gas | Gas | Gas |
Location | Internal | Internal | Internal | Internal |
Condensing? | Condensing | Condensing | Condensing | Condensing |
Efficiency Rating | 94.00% | 94.00% | 94.00% | 94.00% |
Band Rating | A | A | A | A |
LPG Compatible? | Yes | Yes | No | No |
Parts and Labour Warranty in months | 60 | 60 | 60 | 60 |
Heat Exchange Warranty in months | 60 | 60 | 60 | 60 |
Output kW | 20.4 | 25.7 | 32.2 | 30.1 |
Mounting | Wall Mounted | Wall Mounted | Wall Mounted | Wall Mounted |
Flow Rate | 10.5 | 13 | 14.3 | 15.9 |
Price from | £1,130 | £1,225 | £1,400 | £1,380 |
Price to | £1,175 | £1,275 | £1,460 | £1,435 |
ERP Heat | A | A | A | A |
ERP Water | A | A | A | A |
TOTAL | 87.07% | 86.83% | 86.40% | 86.45% |
The Vaillant ecoTEC plus storage boiler finishes in a worthy second place with a similarly impressive list of useful functions and features including:
- Being hand-built on the award-winning Derbyshire manufacturing plant so you can feel confident you are supporting the national economy
- A promise to deliver hot water within 5 seconds and the capacity to stream up to 20 litres per minute as long as your water mains supply will allow it.
- A 5-year warranty as standard with the option to extend this to 7 or even 10 years if installed by a certified Vaillant Advance installer so you can choose your cover according to your needs and budget
- High performance cased in a compact size of 720mm x 440mm x 600mm so you have options for installation location depending on your property
- Quiet Mark accreditation so you can relax knowing your boiler isn’t going to go bump in the night.
3rd place – Viessmann B1LD Vitodens 111-W Boiler
Make | Viessmann | Viessmann |
Model Name | B1LD Vitodens 111-W 26 Boiler | B1LD Vitodens 111-W 35 Boiler |
Type | Storage combi | Storage combi |
Power | Gas | Gas |
Location | Internal | Internal |
Condensing? | Condensing | Condensing |
Efficiency Rating | 89.50% | 89.50% |
Band Rating | B | B |
LPG Compatible? | Yes | Yes |
Parts and Labour Warranty in months | 60 | 60 |
Heat Exchange Warranty in months | 60 | 60 |
Output kW | 26 | 35 |
Mounting | Wall Mounted | Wall Mounted |
Flow Rate | 18 | 18 |
Price from | £1,520 | £1,560 |
Price to | £1,580 | £1,620 |
ERP Heat | A | A |
ERP Water | N/A | N/A |
TOTAL | 77.91% | 77.82% |
In third place and the highest finishing Viessmann range is the B1LD Vitodens 111-W available with a 26kw output for smaller homes and a 35kw output for larger homes.
Both models boast an impressive flow rate of 18 litres per minute meaning that you and members of your family should be able to use two taps and a shower at the same time without suffering any loss of pressure.
The company states that this boiler range can fill a standard bath in around 8 minutes while also providing water to a washbasin or sink at the same time.
The boiler comes with a five year warranty as standard although this may be increased to a period of 10 years if fitted by an installer trained by and licensed to Viessmann.
With this range, Viessmann has made a conscious effort to cut back on the number of internal components – this is great as there is less that can go wrong and the boiler operates really quietly.
4th place – Viessmann B2TB Vitodens 222-F Storage Boiler
Make | Viessmann | Viessmann | Viessmann |
Model Name | B2TB Vitodens 222-F 19 Storage Boiler | B2TB Vitodens 222-F 26 Storage Boiler | B2TB Vitodens 222-F 35 Storage Boiler |
Type | Storage combi | Storage combi | Storage combi |
Power | Gas | Gas | Gas |
Location | Internal | Internal | Internal |
Condensing? | Condensing | Condensing | Condensing |
Efficiency Rating | 89.30% | 89.40% | 89.50% |
Band Rating | B | B | B |
LPG Compatible? | Yes | Yes | Yes |
Parts and Labour Warranty in months | 60 | 60 | 60 |
Heat Exchange Warranty in months | 60 | 60 | 60 |
Output kW | 19 | 26 | 35 |
Mounting | Wall Mounted | Wall Mounted | Wall Mounted |
Flow Rate | 18 | 20 | 20 |
Price from | £2,510 | £2,645 | £2,915 |
Price to | £2,610 | £2,755 | £3,035 |
ERP Heat | A | A | A |
ERP Water | A | A | N/A |
TOTAL | 75.48% | 75.15% | 74.49% |
In fourth place in our list is the floor standing Viessmann B2TB Vitodens 222-F storage boiler range with a total HomeSage score of 74.49%-75.48%.
This boiler came in first place due to its wealth of features including:
- A highly convenient 7” full colour touchscreen control panel that is compatible with the ViCare heating control app, making setting your home heating easy whilst you’re on the go
- Excellent energy efficiency and lower carbon emissions thanks to the newly developed MatriX-Plus internal burner so your environmental footprint is smaller
- WiFi integration to link your boiler to your smart device and so the boiler is connected to the internet for extra control and diagnostics
- Operational reliability thanks to the integral Lambda Pro Plus combustion controller which has been designed for longevity so your boiler will stand the test of time
- A fluorescent light guide on the energy cockpit which displays boiler information clearly and lets you know the boiler is working correctly and efficiently at a glance, even in a dimly lit cupboard
- A 100-litre loading cylinder for extra hot water needs fitted into a compact measuring casing of 1400mm x 600mm x 595mm and a weight of 111.5kg for easy installation.
This boiler won the Which? Best Buy award in September 2019 and comes complete with a standard warranty of 5-years.
The warranty can be extended upon installation and the internal Inox-Radial heat exchanger has a 10-year guarantee for extra security.
5th place – Viessmann B2UB Vitodens 242-F Storage Boiler
Make | Viessmann | Viessmann |
Model Name | B2UB Vitodens 242-F 19 Storage Boiler | B2UB Vitodens 242-F 26 Storage Boiler |
Type | Storage combi | Storage combi |
Power | Gas | Gas |
Location | Internal | Internal |
Condensing? | Condensing | Condensing |
Efficiency Rating | 89.30% | 89.30% |
Band Rating | B | A |
LPG Compatible? | Yes | Yes |
Parts and Labour Warranty in months | 24 | 24 |
Heat Exchange Warranty in months | 24 | 24 |
Output kW | 19 | 26 |
Mounting | Wall Mounted | Wall Mounted |
Flow Rate | 16.4 | 19 |
Price from | £2,645 | £2,915 |
Price to | £2,755 | £3,035 |
ERP Heat | A | A |
ERP Water | N/A | A |
TOTAL | 72.65% | 74.49% |
The Viessmann B2UB Vitodens 242-F storage boiler just makes it into the top 5 with an overall HomeSage score of 72.65% for the 19kW model and 74.49% for the 26kW model.
This combi storage boiler benefits from the following appealing features:
- Easy to operate full colour 5” touchscreen control panel for maximum usability, that can also be controlled via the app on your smart device so you can set your hot water needs even when you’re out and about
- An internal Matrix cylinder burner with a lambda pro control combustion and controller to ensure consistently high energy efficiency with a clean combustion, meaning you pay less, and your boiler lasts longer
- A modest floor-standing area of just 0.4m2 meaning it can be installed in a small space, the overall dimensions are 1875mm x 600mm x 595mm which are fairly compact for a floor-standing unit
- An energy efficiency rating of ‘B’ alongside a standard warranty of 2-years providing you follow the rules and regulations regarding installation and annual servicing
Save up to 54% on your boiler installation with HomeSage
We offer a completely free, no obligation service to see if you could save up to 54% on the cost of the supply and installation of a new storage combi boiler.
Simply fill in our online form and we will get in touch with three or four local, reliable and Gas Safe regulated engineers who will then contact you directly with a free quote to supply and install an energy efficient storage combi boiler system.
Even if you decide not to go ahead with any of the options from the local firms, the service is 100% free for you and there is no obligation on you to accept a quote.