SpecDirectory

Bosch ZBR 21-3vsWeil-McLain ULTRA-230

Side-by-side boiler comparison

Bosch ZBR 21-3

AFUE

95%

Fuel

Natural Gas, Propane Gas

Type

Boiler

Weil-McLain ULTRA-230

AFUE

94%

Fuel

Natural Gas, Propane Gas

Type

Boiler

Hot Water

Can integrate

Key differences

Both models are closely matched on afue: 95.0 vs 94.0 %. The Bosch ZBR 21-3 is larger at 95 % versus 94 %.

Efficiency

SpecBoschWeil-McLain
AFUE(%)9594
Fuel TypeNatural Gas, Propane GasNatural Gas, Propane Gas
Can Integrate Hot Water HeatingNoYes

Configuration

SpecBoschWeil-McLain
Product TypeBoilerBoiler
Model NameGreenstarULTRA
View ZBR 21-3 specs →View ULTRA-230 specs →

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