What we measured Tested May 2026 by Marta Kowalska, home heating tester
6.4 kWHeat output
90.1%Efficiency
0.4 kg/hPellet use (low)
2.4 kWMin turndown
La Nordica Extraflame Viviana Plus: full specifications | Nominal heat output | 6.4 kW |
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| Heats rooms up to | ~55 m² |
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| Seasonal efficiency (measured) | 90.1% |
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| Minimum turndown | 2.4 kW |
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| Hopper capacity | 13 kg |
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| Pellet consumption | 0.4 to 1.4 kg/h |
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| Flue diameter | 80 mm |
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| Noise (auger and fan) | 40 dB low / 48 dB high |
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| Weight | 95 kg |
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| Standard | EN 14785, Ecodesign 2022 |
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| Typical UK price | £1,249 |
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Who is the La Nordica Viviana Plus for?
The Viviana Plus is the right stove for a small or well-insulated room: a snug, a study, a modern new-build living room or any space up to around 55 m². In that brief it is excellent. Its 6.4 kW output is matched to the room, so it runs in its efficient band rather than idling, and it turns down to a gentle 2.4 kW for mild spring and autumn days when a bigger stove would be uncomfortably hot. Its slim 95 kg cast body suits a compact room, and it sipped just 0.4 kg of pellets an hour on its lowest setting, the least of any stove here. If your room is small, this is the stove that fits.
It is the wrong stove for a large space. Ask it to heat a big open-plan living room and it will fall short, running flat out and never quite warming the room, so for those spaces you should step up to the 8 kW Ecoteck Francesca or the 9 kW Ravelli Holly 9. Its lower output also makes it a more niche stove, so it has a narrower appeal on resale. But for a genuinely small or modern, well-insulated room, buying a right-sized stove like this is the smart, efficient choice that an oversized stove can never match.
How the La Nordica Viviana Plus performs
Why a smaller stove is the right choice here
The most important thing to understand about the Viviana Plus is that its low output is deliberate and correct for a small room. An oversized stove in a small space is forced to run on its lowest setting almost constantly, where any pellet stove burns least cleanly, glazes its glass and cycles on and off, leaving the room hot then cool. The Viviana Plus avoids all of that by being sized to the room: at 6.4 kW nominal, with a turndown to a measured 2.4 kW, it spends its time in its efficient mid-band, holding a steady, even warmth. This matches the guidance in the manufacturer's EN 14785 declaration, which lists a wide modulation range precisely so the stove can match a small heat demand.
Efficiency and pellet use
This is the stove's standout strength. We measured its seasonal efficiency at 90.1%, the second-highest in this test behind only our overall winner, and on its lowest setting it burned just 0.4 kg of pellets an hour, the least of any stove here. Combined, those figures make the Viviana Plus the cheapest stove here to run in a small room: it wastes almost none of the pellet's energy and uses very little of it on a mild day. On the UK pellet prices tracked by the Department for Energy Security and Net Zero, a right-sized, 90-percent-efficient stove like this is genuinely economical to run through a whole season.
Noise, warmth and build
At 40 dB on low and 48 dB at high output, the Viviana Plus is among the quieter stoves on test, comfortable in a snug or study where you sit close to it. The cast body holds and radiates heat well for its size, giving an even, settled warmth rather than a blast of hot air. The 13 kg hopper suits the low pellet use, lasting well in a small room before it needs a refill. The build quality is solid and the finish neat, in keeping with La Nordica's long heating heritage, and over our test run the glass stayed clean thanks to the efficient, well-modulated burn.
The honest downsides
There are two, and both follow directly from its small size. First, it simply does not have the output for a large or draughty room, so it is the wrong stove for an open-plan space and you must be honest about your room size before buying. Second, its niche, small-room positioning means it has a narrower second-hand market than a mainstream 8 kW stove, so it may be a little harder to sell on. Neither is a flaw in how it heats; both are inherent to a deliberately gentle stove, and irrelevant if you are buying it for the small room it is designed for.
The good
- Low 6.4 kW output will not overheat a small or modern room
- Second-highest efficiency on test at a measured 90.1%
- Turns down to a gentle 2.4 kW for mild days
- Used the least pellet of any stove, 0.4 kg/h on low
- Slim 95 kg cast body suits a snug or new build
The not-so-good
- Too small for a large open-plan space
- Lower output narrows its resale appeal
- 13 kg hopper, in line with the compact class
- No smart app control at this price
Best for: a small, modern or well-insulated room, a snug or a study, where a right-sized 6.4 kW stove runs efficiently instead of idling. Not the pick for a large open-plan room (try the Ravelli Holly 9 or MCZ Suite) or anyone who wants smart app control.
Sources and references
- BS EN 14785:2006, Residential space heating appliances fired by wood pellets, used to verify the declared output and turndown range.
- La Nordica Extraflame Viviana Plus technical data sheet, manufacturer's published declaration of performance.
- UK Department for Energy Security and Net Zero, quarterly domestic fuel price statistics, used for the running-cost comparison.
