Bosch Greenstar 131 Combi Boiler
Bosch Greenstar 131 Combi Boiler Review
The Bosch Greenstar 131 is a 131K BTU residential combination boiler. Smaller variant of the Bosch Greenstar 151. Sized for smaller homes (1,200-1,800 sq ft) with modest hydronic space-heat demand.
Specs: 131,000 BTU input, AFUE 95% (condensing), 3.9 GPM DHW at a 70°F rise, modulating burner with 5:1 turndown. Stainless steel heat exchanger. PVC condensing venting. 15-year warranty on heat exchanger.
The Greenstar 131 is right-sized for smaller homes with combined space-heat + DHW needs. Right answer for smaller homes converting from oil-fired boiler + separate water heater to a single high-efficiency combi.
About $7,000-$9,500 installed depending on hydronic system modifications. Right buyer: smaller home (1,200-1,800 sq ft) in regions with established Bosch dealer presence.
- Natural gas combustion — faster recovery than electric resistance at comparable tank size
- UEF 0.95 — top-tier efficiency; qualifies for Inflation Reduction Act §25C residential credit
- 10-year warranty — solid above-average coverage for this class
- High 131K BTU input — rapid recovery for large-volume commercial-residential applications
- Tank standby heat loss — tankless or heat-pump alternatives eliminate this continuous efficiency gap