Boilers with feeder for coal
Defro Duo Uni
DESCRIPTION
DEFRO DUO UNI boilers are the other two-furnace boilers. Bottom chamber is equipped with innovative trough burner allowing combustion of eco pea coal, qualified fines and crops grains. Upper chamber is created by fixed water-cooled grate, allowing periodical combustion of the other fuels and start-up of boiler in emergency situations. Heat exchanger of boilers is completely made of boiler steel of thickness 6-10 mm, while the individual components endangered with action of flames and substances in the flue gases - are made of thickness even 10-12 mm. Boilers are equipped with components increasing operational safety e.g. flap opening sensor, double protection against ignition of fuel in hopper - first implemented by the controller, the second - by automatic, water extinguishing system STRAŻAK (FIRE FIGHTER). Version with innovative controller with touch panel is available as a standard.
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Heat exchanger made of certified high-grade steel; |
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controller K1 with colour touch panel servicing 4 pumps /central heating, hot utility water, circulation, floor pump/. Possibility to operate mixing valves, control using GSM or INTERNET*; adjustable angle of control panel |
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5 years of warranty for heat exchanger tightness, 2 years for the remaining components and efficient operation of boiler |
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high thermal efficiency reaching 90% thanks to increased heat recovery from flue gases
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boiler adapted for installation in closed circuit in version DEFRO DUO UNI NZ |
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bottom furnace chamber with highly effective trough burner |
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bottom furnace chamber with highly effective trough burner
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two furnace chambers: bottom with automatic burner, upper for wood combustion /for manual charging/ |
(*) - extra payable equipment, installed on Customer’s request
Name of the boiler | Defro Duo Uni | |||||
Specification/boiler type | Unit | 15 | 20 | 25 | 35 | 50 |
Power range | kW | 4,5-15 | 6,0-20 | 7,5-25 | 10,5-35 | 15,0-50 |
Heating area |
m2 |
1,9 | 2,4 | 2,8 | 3,2 | 4,4 |
Area of heated rooms 1 |
m2 |
to 200 | to 260 | to 300 | to 370 | to 580 |
Fuel tank capacity 2 |
kg | ~178 | ~178 | ~178 | ~228 | ~228 |
Optimum thermal efficiency | % | ~90,3-90,9 | ||||
Energy efficiency class | - | D | C | C | C | C |
Max. permissible operation pressure |
bar | opened system: 1,5 / closed system: 2,5 | ||||
Required flue gas draught | Pa | 24 | 26 | 28 | 31 | 34 |
Max. temp. of water on supply | °C | 65/80 | ||||
Boiler weight 3 |
kg | 459 | 502 | 538 | 614 | 777 |
Boiler water tank capacity | l | 80 | 106 | 114 | 120 | 172 |
Chimney section | cmxcm | 14x14 | 14x14 | 15x15 | 18x18 | 20x20 |
Chimney section |
Ø mm |
160 | 160 | 170 | 200 | 230 |
Minimum chimney height |
m |
7 |
7,5 |
8 |
9 |
10 |
Width | mm | 1195 | 1195 | 1257 | 1298 | 1287 |
Depth |
mm |
950 |
1060 |
1060 |
1090 |
1310 |
Height 4 |
mm | 1664 | 1664 | 1664 | 1715 | 1715 |
Diameter of supply and return Dn |
mm |
G1 ½” |
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Diameter of flue | mm | 159 | 159 | 178 | 194 | 194 |
Supply |
V/Hz |
~230/50 |
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Maximum power consumption (operation / firing) |
W | 873/123 | 873/123 | 873/123 | 890/140 | 890/140 |
Height to bottom edge of flue |
mm |
1258 |
1258 |
1252 |
1270 |
1270 |
Dimensions of charging chamber and charging hole |
width depth height width x height |
308 420 203 308 x 398 |
308 529 191 308 x 398 |
358 529 228 358 x 398 |
408 529 253 408 x 398 |
404 750 223 404 x 398 |
1 Maximum area of heated rooms estimated for unit heat demand q=85 W/m².
2 Fuel tank capacity for charging density 0,8 kg/dm³.
3 Boiler weight depends on the equipment.
4 Height of boiler can be additionally adjusted by means of provided levelling legs.
Legs regulation varies from 38 to 50 mm.
5 Details of burning pellets can be found in the manual of the boiler.
6 Extra paid option, installed on the customer’s request.
DOWNLOAD
DEFRO
Opening hours: Monday - Friday, from 08:00 to 16:00
00 48 41 303 91 31