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PELLET DUO — Automatic, Multi-Fuel Hydronic Heat
Heating Capacity: Up to 3,000 ft²
Entry-size PELLET DUO with automatic multi-fuel feed and a manual firebox for backup or supplemental heat.
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Installed in real homes and workshops
This boiler gives us a powerful, flexible heating system that can be adjusted to suit our home.
A flexible boiler built for real-world heating
A homeowner shares his MBTEK boiler installation, explains how the system operates, and walks through the adjustments used to optimize its performance.
High-performance automatic pellet boiler designed for maximum efficiency, long autonomy, and multi-fuel flexibility. Ideal for heating large homes with minimal maintenance.
| Heat | Up to 3,000 ft² |
|---|---|
| BTU | 65K |
| Weight | 970 lb |
| Width | 43 in |
| Depth | 24 in |
| Height | 50 in |
| Manual firebox | 18 gal, max log 15 in |
| Automatic hopper | 93 gal / 442 lb pellets |
| Efficiency | 92% |
| Autonomy | 4–10 days, up to 2 weeks depending on usage |
| Certification | EN 303-5:2012 |
Answers
Pellet Duo is a fully automatic, multi-fuel pellet boiler for hydronic heating, built around an auger-fed automatic hopper plus — on the 20/50/95 models — a manual firebox for backup or supplemental solid-fuel heat.
Pellet Duo 20 covers up to 3,000 ft², Pellet Duo 50 up to 6,200 ft², and Pellet Duo 95 up to 12,000 ft². For larger commercial or industrial loads, see the Pellet Duo Large/Industrial sizes (150–1000).
Yes — pellets, grains, corn, or biomass feed automatically through the auger-fed hopper. The 20/50/95 models also include a separate manual firebox as an optional backup fuel path, but automatic operation doesn't require it.
Fuel use depends on hopper size and usage. Regular-tier models (20/50/95) typically run 4–10 days of autonomy — up to two weeks — between refills.
Wood pellets, grains, corn, or biomass through the automatic hopper, plus cut logs through the manual firebox on the 20/50/95 models.
Yes — Pellet Duo pairs with a domestic hot water tank such as the APOLLO DHW80 to cover both space heating and domestic hot water from the same boiler.
The Pellet Duo 20, 50, and 95 include a manual firebox in the specs table. This gives backup or supplemental solid-fuel flexibility.
Pellet Duo is rated at 92% efficiency and certified to EN 303-5:2012.
A buffer tank or boiler protection valve can help manage heat output and protect the system depending on your hydronic design. Confirm the right accessories for your installation with MBTEK.
Plan for hopper refill access, venting, and hydronic connections sized to the model's manual-firebox and automatic-hopper dimensions. Confirm exact clearances and venting requirements with MBTEK before installation.
Routine maintenance includes ash removal, keeping the hopper supplied, and periodic cleaning and inspection per the controller manual's schedule.
Running cost depends on fuel price and usage, but Pellet Duo's 92% efficiency and multi-fuel flexibility (pellets, grains, corn, or biomass) are designed to reduce cost per BTU versus wood, diesel, or oil heating.
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Need an installer?We made it easy for you.
Listed installers are independent contractors, not MBTEK employees. They're skilled professionals familiar with our products and capable of efficient installation.
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