OWB – Oil Fired Water Boiler Series 2
0.70 to 1.75 GPH Input
Factory tested
Easy service
Swing-away burner door
Low draft loss
Top access cleanout cover
Plug-in wiring harness
High efficiency oil burner
Flame retention head design
Solenoid valve
PSC motor
Solid state ignitor
Rear flue outlet
Cast iron sections with built-in air separator
Insulated heavy-gauge steel jacket
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Boiler Model | Burner Input | AHRI Certified Ratings | Minimum Chimney Size (x 15′ High) | ||||
GPH | MBH | Heating Capacity MBH | Net Rating (water) MBH | Seasonal Efficiency AFUE% | Rectangle | Round | |
OWB-3 | 0.70 | 98 | 86 | 75 | 86.4 | 8″ x 8″ | 6″ |
OWB-3* | 0.95 | 133 | 114 | 99 | 85.0 | 8″ x 8″ | 6″ |
OWB-4 | 1.00 | 140 | 122 | 106 | 86.2 | 8″ x 8″ | 6″ |
OWB-4* | 1.20 | 168 | 145 | 126 | 85.0 | 8″ x 8″ | 6″ |
OWB-5 | 1.20 | 168 | 147 | 128 | 86.1 | 8″ x 8″ | 7″ |
OWB-5* | 1.45 | 203 | 175 | 152 | 85.0 | 8″ x 8″ | 7″ |
OWB-6 | 1.40 | 196 | 171 | 149 | 86.1 | 8″ x 8″ | 7″ |
OWB-6* | 1.75 | 245 | 212 | 184 | 85.0 | 8″ x 8″ | 7″ |
Thermoflo has determined the boilers listed below are compliant with ENERGY STAR® Program 3.0 when installed with (optional) OVD kit. | |||||||
OWB-3-T-S2-D | 0.70 | 98 | 87 | 85 | 87 | 8″ x 8″ | 6″ |
OWB-4-T-S2-D | 1.00 | 140 | 123 | 107 | 87 | 8″ x 8″ | 6″ |
OWB-5-T-S2-D | 1.20 | 168 | 148 | 129 | 87 | 8″ x 8″ | 7″ |
OWB-6-T-S2-D | 1.40 | 196 | 173 | 150 | 87 | 8″ x 8″ | 7″ |
Boiler Model | Burner Input | AHRI Certified Ratings | Minimum Chimney Size (x 15′ High) | ||||
GPH | MBH | Heating Capacity MBH | Net Rating (water) MBH | Seasonal Efficiency AFUE% | Rectangle | Round | |
OWB-3 | 0.70 | 98 | 86 | 75 | 86.4 | 8″ x 8″ | 6″ |
OWB-3* | 0.95 | 133 | 114 | 99 | 85.0 | 8″ x 8″ | 6″ |
OWB-4 | 1.00 | 140 | 122 | 106 | 86.2 | 8″ x 8″ | 6″ |
OWB-4* | 1.20 | 168 | 145 | 126 | 85.0 | 8″ x 8″ | 6″ |
OWB-5 | 1.20 | 168 | 147 | 128 | 86.1 | 8″ x 8″ | 7″ |
OWB-5* | 1.45 | 203 | 175 | 152 | 85.0 | 8″ x 8″ | 7″ |
OWB-6 | 1.40 | 196 | 171 | 149 | 86.1 | 8″ x 8″ | 7″ |
OWB-6* | 1.75 | 245 | 212 | 184 | 85.0 | 8″ x 8″ | 7″ |
Thermoflo has determined the boilers listed below are compliant with ENERGY STAR® Program 3.0 when installed with (optional) OVD kit. | |||||||
OWB-3-T-S2-D | 0.70 | 98 | 87 | 85 | 87 | 8″ x 8″ | 6″ |
OWB-4-T-S2-D | 1.00 | 140 | 123 | 107 | 87 | 8″ x 8″ | 6″ |
OWB-5-T-S2-D | 1.20 | 168 | 148 | 129 | 87 | 8″ x 8″ | 7″ |
OWB-6-T-S2-D | 1.40 | 196 | 173 | 150 | 87 | 8″ x 8″ | 7″ |
Brochures & Sales Collateral
OWB Series 2 – Sales Flyer
Warranty Information
OWB Series 2 – Commercial Warranty
OWB Series 2 – Residential Warranty