Velocity Boiler Works PHX1250C-OvsViessmann CI2-1500
Side-by-side commercial boiler comparison
Velocity Boiler Works PHX1250C-O
Thermal Efficiency
97%
Input Rate
1250MBTU/hr
Turndown Ratio
10.00
Application
Outdoor
Viessmann CI2-1500
Thermal Efficiency
97.3%
Input Rate
1500MBTU/hr
Turndown Ratio
30.00
Application
Indoor
Key differences
Both models are closely matched on thermal eff: 97.0 vs 97.3 %. The Viessmann CI2-1500 is larger at 1500 MBTU/hr versus 1250 MBTU/hr.
Performance
| Spec | Velocity Boiler Works | Viessmann |
|---|---|---|
| Thermal Efficiency(%) | 97 | 97.3 |
| Full-Load Input Rate(MBTU/hr) | 1250 | 1500 |
| Turndown Ratio | 10.00 | 30.00 |
Configuration
| Spec | Velocity Boiler Works | Viessmann |
|---|---|---|
| Application | Outdoor | Indoor |
| Control Type | Multi-stage | Multi-stage |
| Model Name | Phantom-XL | CI2-1500 |