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Takagi

Takagi T-D2-IN-LP Indoor Condensing Tankless Water Heater (Propane)

Model T-D2-IN-LP
4.2/5 from 80 ratings
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Btu
199000
Venting
PVC Direct Vent
Fuel Type
Propane
Tank Type
Tankless
Capacity Gpm
10
Energy Factor
0.95

Takagi T-D2-IN-LP Indoor Condensing Tankless Water Heater (Propane) Review

The Takagi T-D2-IN-LP is the propane variant of Takagi's T-D2 flagship condensing tankless. Indoor liquid propane configuration with full stainless heat exchanger.

Specs: 199,000 BTU LP input, UEF 0.95 condensing, 10.0 GPM at a 35°F rise, dual stainless heat exchanger, PVC condensing venting. 15-year warranty on heat exchanger.

The propane variant adds typical $200-$400 premium over the natural gas equivalent. The T-D2 platform shares engineering with Rheem RTGH series (Rheem owns Takagi).

About $2,000 unit, $4,000 installed for propane retrofit. Right buyer: rural propane home with 3+ bath demand wanting Takagi/Rheem premium engineering at full 199K BTU capacity.

Pros
  • On-demand operation at 10 GPM — no standby heat loss; unlimited hot water if demand is within flow-rate capacity
  • UEF 0.95 — top-tier efficiency; qualifies for Inflation Reduction Act §25C residential credit
  • 15-year warranty — top-tier coverage for residential water heaters
  • High 10 GPM output — serves 3+ simultaneous hot-water fixtures in most US climates
Cons
  • Requires dedicated 199K BTU gas supply line — undersized gas piping is the leading cause of flow-rate shortfalls

Full Specifications

Brand
Takagi
Model Number
T-D2-IN-LP
Btu
199000
Venting
PVC Direct Vent
Fuel Type
Propane
Tank Type
Tankless
Capacity Gpm
10
Energy Factor
0.95
Warranty Years
15

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