Closed Combustion

Sealed combustion boilers use fans and ducted air vents which improve the performance of a Low Mass Boiler.

They also provide low NOx for emission requirements. Generally, these units also ship with upgraded ignition systems that allow for staged thermal performance for different seasonal loads.

The reason this technology was developed was to meet the newer anti-smog regulations, which were largely driven by NOx emission. These systems burn the fuel more thoroughly and release less smog.

BioTherm offers three closed combustion boiler models: HiDelta, Delta Limited, and MVB.


HiDelta

BioTherm HiDelta
Model Number Full Input in BTUH Flue Diameter Stages
H3-HD101 100,000 4" 2
H3-HD151 150,000 4" 2
H3-HD201 199,000 5" 2
H3-HD251 250,000 5" 2
H3-HD301 299,000 5" 2
H3-HD401 399,000 5" 2
H3-302B 300,000 5" 2
H3-402B 399,000 6" 2
H3-502B 500,000 6" 2
H3-652B 650,000 8" 2
H3-752B 700,000 8" 2
H3-902B 900,000 8" 2
H8-992B 990,000 10" 3
H9-1262B 1,260,000 12" 4
H9-1532B 1,530,000 12" 4
H9-1802B 1,800,000 14" 4
H9-2002B 1,999,000 14" 4
H9-2072B 2,070,000 14" 4
H9-2342B 2,340,000 16" 4

Delta Limited

BioTherm Delta Limited
Model Number Full Input in BTUH Flue Diameter Stages
H4-399B 399,000 6" On/off
H3-499B 500,000 6" 2
H3-649B 650,000 8" 2
H3-749B 750,000 8" 2
H3-899B 900,000 8" 2
H3-989B 990,000 10" 2
H8-1259B 1,260,000 12" 3
H9-1529B 1,530,000 12" 4
H9-1799B 1,800,000 14" 4
H9-1999B 1,999,000 14" 4
H9-2069B 2,070,000 14" 4
H9-2339B 2,340,000 16" 4

MVB

BioTherm MVB
Model Number Full Input in BTUH Flue Diameter Stages
H7-504A 500,000 8" Modulating
H7-754A 750,000 10" Modulating
H7-1104A 1,100,000 10" Modulating
H7-1504A 1,500,000 12" Modulating
H7-2004A 1,999,000 14" Modulating