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FREE SHIPPING
UNICA Pellet Hydro Stove
$0.00
$0.00
- Your heating bill will noticeWood pellets cost a fraction of oil or gas — and the Unica burns them at over 93% efficiency. That combination hits your wallet in the best possible way.
- One stove, whole houseThe water jacket pushes heat to every room — radiators, radiant floors, fan coils, even your hot water tank. One fire does it all.
- Fuel you can feel good aboutWood pellets are renewable, low-emission, and sold at farm stores and hardware chains across North America. A cleaner way to stay warm.
- Built to stay cleanLift the top cover, screw in the handle, move it up and down. Two minutes, once a week. That's all the maintenance this stove asks for.
- Real people, real answersNot a chatbot. Our hydronic HVAC team picks up the phone and helps you get the system right — before the install and after.
Product details
UNICA Pellet Hydro Stove – High-Efficiency Water-Jacketed Pellet Stove
The UNICA pellet hydro stove combines modern European design with powerful hydronic heating performance. Designed as a water-jacketed pellet stove, it can support space heating through a connected hydronic system while adding a clean, contemporary look to the home.
Key Benefits
- High-efficiency operation with energy conversion efficiency above 93%
- Water-jacketed design for connection to a hydronic heating system
- Multiple output options available from 8 kW to 30 kW
- Automatic combustion management for reliable day-to-day operation
- Room temperature control via thermostat
- Weekly chrono programming for scheduled operation
- Manual turbulator cleaning system for easier maintenance
- Spacious ashtray compartment to simplify cleaning
- Optional Wi-Fi module for remote control by smartphone
- Modern compact design available in multiple color finishes
Specifications
- Fuel Type: Wood pellets Ø6–Ø8 mm
- Maximum Output: 8 / 12 / 15 / 18 / 24 / 30 kW
- Energy Efficiency: >93% to >94% depending on model
- Working Pressure: 0.5–2.0 bar
- Max Water Temperature: 90°C
- Water Jacket Capacity: 16–48 L depending on model
- Pellet Hopper Capacity: 22–45 kg depending on model
- Exhaust Gas Pipe: Ø80 mm
- Fresh Air Pipe: Ø60–Ø76 mm depending on model
- Recommended Chimney Draft: 12 Pa
- Electrical Supply: 230V / 50Hz
- Electrical Consumption: 60 / 310 W
- Operating Environment: 5–40°C
Customer Success Stories
The Apollo heat pump system is very efficient, quiet, and easy to install. It stands out for its clear design, well-organized components, and advanced features like a touchscreen and remote monitoring through an app. It also allows precise temperature control and includes an electric backup for very cold conditions. Overall, it's a reliable and practical system.
Heats my home nicely and economically. The cold weather does not seem to affect the pump. Overall I'm very happy with the system. The techs have been very helpful whenever I have had questions regarding installation, etc.
Since installing the Apollo heat pump, our energy bills have plummeted. It pulls heat right out of the air outside, even when it's freezing, and uses a fraction of the electricity our old system did. It's incredibly efficient
I was skeptical about a heat pump in our cold climate, but the Apollo proved me wrong. It consistently delivers strong, comfortable heat to our entire home, even during the deepest winter freezes. It's a truly robust system
Upgrading to the Apollo air-to-water heat pump was the best decision for our home. It integrated perfectly with our existing radiant floor heating. It runs quietly outside and provides perfectly even, comfortable heat inside
You can tell just by looking at the Apollo unit that it's built to last. It handles the elements outside without a problem and operates surprisingly quietly. It gives us total peace of mind knowing we have such a dependable system
Maximizing Efficiency with Apollo Heat Pump
Economical performance that isn't affected by low temperatures.
Reliable Heating in Cold Weather
Economical performance that isn't affected by low temperatures.
Incredible Energy Savings
Slashing utility bills with high-efficiency air-to-water technology
Reliable Heat, No Matter the Weather
Powerful performance that stands up to freezing temperatures
The Ultimate Home Heating Upgrade
Seamlessly integrating with existing radiant or hydronic systems
Built to Weather Any Storm
Heavy-duty construction for years of reliable, quiet operation
Maximizing Efficiency with Apollo Heat Pump
Reliable Heating in Cold Weather
Incredible Energy Savings
Reliable Heat, No Matter the Weather
The Ultimate Home Heating Upgrade
Built to Weather Any Storm
Mareli Systems Unica
Main Features
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Heat your whole house for less
Wood pellets cost a fraction of oil or propane — and the Unica converts over 93% of that fuel into usable heat. Your heating bill notices the difference fast.
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One fire heats everything
Radiators, radiant floors, fan coils, and domestic hot water — all from a single stove. The built-in water jacket does the heavy lifting so your whole system stays warm.
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Clean in two minutes, once a week
Pop the top cover, screw in the included handle, move it up and down. That's it. No special tools, no mess, no guesswork — the Unica is built to make maintenance genuinely easy.
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Warm before you walk in the door
Set daily, weekly, or weekend schedules right from the display. The stove ignites on its own, gets up to temperature, and shuts itself down — you just enjoy the warmth.
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Hot showers included
Wire in a second pump and a DHW buffer tank and the Unica heats your domestic hot water too. One appliance, one fuel, two jobs done.
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A fuel you can actually get
Bagged wood pellets are sold at hardware stores, farm co-ops, and online across North America. Store them dry, pour them in the hopper, and the Unica handles the rest.
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Works with what you already have
Standard water connections and normal system pressure mean the Unica connects to most existing hydronic setups without extra parts or surprises.
Right for small homes or large ones
Six output sizes from 8 to 30 kW cover everything from a tight bungalow to a large two-storey. Pick the one that fits and it will run at its most efficient all season.
Burns clean, stays clean
Designed for certified A1/A2 pellets with less than 1.2% ash — which means less buildup, less maintenance, and cleaner air out the flue.
You're never left on your own
MBTEK's team knows hydronic systems inside out. From sizing to commissioning, we're here before, during, and after the install.
Technical specifications
All values from Mareli Systems Unica user manual rev. 2.0. Output-specific values shown as a range across the 8/12/15/18/24/30 kW models.
| Maximum output | 8 / 12 / 15 / 18 / 24 / 30 kW |
|---|---|
| Heated area (0.035 kW/m³) | 220 / 340 / 430 / 510 / 680 / 860 m³ |
| Water jacket capacity | 16 / 30 / 30 / 41 / 41 / 48 L |
| Space heating output | 0.9 / 1 / 1 / 2 / 3 / 4 kW |
| Max water temperature | 90 °C |
| Working pressure | 0.5 – 2.0 bar |
| Energy conversion efficiency | >93% (8/12/15 kW), >94% (18/24 kW), >93% (30 kW) |
| Fuel type | Wood pellets Ø6–Ø8 mm (EN Plus A1/A2 / ISO 17225-2) |
| Pellet bunker volume | 22 / 30 / 30 / 39 / 39 / 45 kg |
| Exhaust gas pipe | Ø80 mm |
| Fresh air pipe | Ø60 mm (8–24 kW) / Ø76 mm (30 kW) |
| Chimney draft | 12 Pa (recommended 12–20 Pa) |
| Electrical supply | 230 V / 50 Hz |
For comparison tables across all six output sizes, or for installation-specific data, refer to the full user manual linked in the Documents tab.
Product documents
Unica Pellet Stove — User Manual rev. 2.0
Full installation, operating, cleaning, error codes, spare parts, and wiring diagram for the Unica 8/12/15/18/24/30 kW.
