Triangle Tube Smart 40 Indirect Water Heater 40-Gallon

Model Smart-40
4.6/5 from 180 ratings
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Price as of May 2026
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Fuel Type
Hydronic
Tank Type
Indirect
Tank Material
Stainless Steel
Warranty Years
Lifetime
Capacity Gallons
40

Triangle Tube Smart 40 Indirect Water Heater 40-Gallon Review

The Triangle Tube Smart 40 is a 40-gallon indirect water heater from Triangle Tube — a premium hydronic specialist brand. Designed to pair with hydronic boilers for DHW production. Stainless steel construction with lifetime warranty.

Specs: 40 gallons stored, fully stainless steel tank construction, internal stainless steel coil heat exchanger, polyurethane foam insulation. Lifetime tank warranty (with compatible Triangle Tube or other approved boiler).

The Smart 40 is sized for 3-4 person households with hydronic boiler installation. Triangle Tube's positioning emphasizes hydronic-specialist engineering — stronger than mass-market indirect tanks in terms of coil heat-transfer efficiency and tank construction quality.

About $2,200 unit, $3,000-$3,800 installed depending on boiler integration. Premium positioning competes with HTP SuperStor SSU-40 and Lochinvar SQUIRE SIT040 at similar capacity and quality tier.

Right buyer: home with Triangle Tube boiler or other premium hydronic system, long-stay primary residence wanting top-tier indirect DHW with lifetime warranty.

Full Specifications

Brand
Triangle Tube
Model Number
Smart-40
Fuel Type
Hydronic
Tank Type
Indirect
Tank Material
Stainless Steel
Warranty Years
Lifetime
Capacity Gallons
40

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