Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
Boilers.ca is a brand of ROMA Heating & Cooling · Licensed gas contractor LGA0202903
Comparison
Verdict in brief
Buderus G615/740 and Buderus G615/820 are two non-condensing boilers from the Bosch Thermotechnology Buderus G615 (Logano G615) line. The Buderus G615/740 is documented at 2,202 MBH net rating, while the Buderus G615/820 is documented at 2,454 MBH net rating. Buderus G615/820 lists 252 MBH more net rating than Buderus G615/740 (2,454 MBH against 2,202 MBH). Buderus G615/820 lists 533 lb more shipping weight than Buderus G615/740 (7,125 lb against 6,592 lb).
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Buderus G615/740 | Buderus G615/820 |
|---|---|---|
| Net AHRI rating, water (gas and oil) | 2,202 MBH | 2,454 MBH |
| Weight, net | 6,592 lb | 7,125 lb |
| Maximum permissible operating pressure | 87 psi | 87 psi |
| Fuels | Heating oil, liquid propane or natural gas | Heating oil, liquid propane or natural gas |
| Number of boiler sections | 11 | 12 |
| Gross output | 2,532 MBH | 2,822 MBH |
| Input rating, gas | 3,031 MBH | 3,392 MBH |
| Input rating, oil | 11 gph | 12 gph |
| Boiler water content | 180 US gal | 195.75 US gal |
| Maximum permissible supply temperature | 248 °F | 248 °F |
Published ratings: the Buderus G615/740 is rated 2,202 MBH net rating; the Buderus G615/820 is rated 2,454 MBH net rating. Buderus G615/820 lists 252 MBH more net rating than Buderus G615/740 (2,454 MBH against 2,202 MBH).
Buderus G615/820 lists 533 lb more shipping weight than Buderus G615/740 (7,125 lb against 6,592 lb). The number of boiler sections differs: the Buderus G615/740 lists 11, while the Buderus G615/820 lists 12. The boiler water content differs: the Buderus G615/740 lists 180 US gal, while the Buderus G615/820 lists 195.75 US gal.
Both records print the same maximum operating pressure (87 psi), fuel (Heating oil, liquid propane or natural gas) and maximum permissible supply temperature (248 °F), per the cited sources.
Bosch Thermotechnology
The Buderus G615/740 is a discontinued commercial cast-iron boiler block with 11 sections, 2,532 MBH gross output and 2,202 MBH net AHRI rating for oil or gas firing.
Bosch Thermotechnology
The Buderus G615/820 is a discontinued commercial cast-iron boiler block with 12 sections, 2,822 MBH gross output and 2,454 MBH net AHRI rating for oil or gas firing.
The Buderus G615/820 lists 2,454 MBH, against 2,202 MBH on the Buderus G615/740, per the cited documentation.
The Buderus G615/820 lists 2,454 MBH, against 2,202 MBH on the Buderus G615/740.
It ships at 7,125 lb against 6,592 lb for the Buderus G615/740, per the cited sources.
A consultation includes a heat-loss review so the size is right the first time.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.
Sources and verification
Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.