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
The discontinued G334X/73 and G334X/132 are large atmospheric cast-iron gas boilers with draft hoods, 3/4" gas connections and 82.7-83.2% combustion efficiency. The /73 fires a 301 MBTU/hr ignition heat load for 249 MBTU/hr nominal output and 217 MBH net IBR with an 8" vent; the /132 fires 541 MBTU/hr for 450 MBTU/hr and 392 MBH net with a 10" vent and 1,265 lb dry weight.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Buderus G334X/73 | Buderus G334X/132 |
|---|---|---|
| Ignition heat load | 301 MBTU/hr | 541 MBTU/hr |
| Nominal output | 249 MBTU/hr | 450 MBTU/hr |
| Combustion efficiency | 82.7 % | 83.2 % |
| Net IBR rating | 217 MBH | 392 MBH |
| Number of burner rods | 5 | 8 |
| Dry weight | 758 lb | 1,265 lb |
| Water volume | 9.2 US gal | 15.6 US gal |
| Vent size | 8" | 10" |
The G334X installation manual describes a large atmospheric gas floor-standing boiler with draft hood and optional vent damper. The four sizes use 5 to 8 burner rods and share the 3/4" gas connection.
Ratings scale: ignition heat load 301 / 378 / 476 / 541 MBTU/hr; nominal output 249 / 314 / 396 / 450 MBTU/hr; net IBR 217 / 273 / 344 / 392 MBH. The brochure prints combustion efficiency 82.7 / 83.1 / 83.2 / 83.2% and no AFUE row.
Physical rows: dry weights 758 / 930 / 1,093 / 1,265 lb; water volumes 9.2 / 11.4 / 13.5 / 15.6 US gal; vent sizes 8" / 9" / 10" / 10". The manual also prints natural-gas and LP orifice tables with 8,501-12,000 ft conversion data. The line is discontinued and documented in the discontinued Buderus products library.
Bosch Thermotechnology
The Buderus G334X/73 is a discontinued atmospheric cast-iron gas boiler with a 301 MBTU/hr ignition heat load, 249 MBTU/hr nominal output and 82.7% combustion efficiency.
Bosch Thermotechnology
The Buderus G334X/132 is a discontinued atmospheric cast-iron gas boiler with a 541 MBTU/hr ignition heat load, 450 MBTU/hr nominal output and 83.2% combustion efficiency.
None - the G334X columns in the Buderus brochure print combustion efficiency (82.7-83.2%) rather than AFUE; AFUE is printed only for the G124X and G234X in that brochure.
The 73 uses 5, the 92 uses 6, the 116 uses 7 and the 132 uses 8, per the dimensions table.
The manual prints natural-gas and LP orifice identification for 0-8,500 ft and 8,501-12,000 ft, with conversion components to be used only as directed by the technical documentation.
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.