Triangle Tube Smart 120 Indirect Water Heater 120-Gallon

Model Smart-120
4.6/5 from 90 ratings
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Price as of May 2026
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Fuel Type
Indirect
Tank Type
Indirect
Energy Factor
0.86
Warranty Years
99
Capacity Gallons
120
First Hour Delivery
380

Triangle Tube Smart 120 Indirect Water Heater 120-Gallon Review

The Triangle Tube Smart 120 is the largest residential indirect water heater in Triangle Tube's Smart line. 120-gallon capacity for very large households or commercial-residential crossover applications.

Specs: 120 gallons stored, fully stainless steel tank construction, internal stainless steel coil heat exchanger, polyurethane foam insulation. Lifetime tank warranty (with compatible boiler).

The 120-gallon capacity exceeds typical residential demand. Use cases: very large households (6+ people), multi-generational homes, small commercial applications, hydronic-boiler installations with heavy DHW demand.

About $3,800 unit, $5,000-$6,500 installed depending on boiler integration. Right buyer: very large residence or commercial-residential crossover with Triangle Tube or other premium hydronic boiler in long-stay scenario.

Full Specifications

Brand
Triangle Tube
Model Number
Smart-120
Fuel Type
Indirect
Tank Type
Indirect
Energy Factor
0.86
Warranty Years
99
Capacity Gallons
120
First Hour Delivery
380

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