Takagi T-D2U - Manual (Page 4)

Residential /Commercial Gas
Ultra-Low NOx
Tankless Water Heaters
Page 4 of 4 www.takagi.com TBGSS01212
Specification
Water heater(s) shall be Model_____________________ as manufactured by Takagi. Water heater(s) shall be a copper coil integral fin and tube construction with quick release brass or
bronze waterways. Heater(s) will be factory assembled and tested.
The heater shall be vented with 4” stainless steel Category III vent pipe or Special BH type gas vent at a distance not to exceed 50’ (equivalent) for 4” vent, terminating vertically or
horizontally as prescribed. Intake air pipe may be of such material as ABS, PVC, galvanized B-Vent, corrugated aluminum or stainless steel, or Category lll / IV stainless steel not to
exceed 50’ (equivalent) for 3” vent.
The heater(s) shall be controlled by an onboard solid-state printed circuit board monitoring incoming and outgoing temperatures with factory installed thermistors, sensing and controlling
flow rate to set point temperature, controlling both air and gas mixture inputs to maintain thermal combustion efficiency. The heater(s) shall also consist of inline fusing, a spark ignition
and sensor system, aluminized stainless steel burners, an air-fuel ratio sensor, a hi-limit temperature switch, modulating and proportional gas valves, a freeze protection sensor with
ceramic heating blocks, and an overheat cutoff fuse.
The water heater(s) shall be CSA listed, exceed the energy efficiency requirements of ASHRAE 90.1b-2007, and shall comply with SCAQMD Rule 1146.2 Ultra-Low NOx Standards.
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T-KJr2U Indoor/Outdoor Pressure Loss
T-K4U Indoor/Outdoor Pressure Loss
T-KJr2U Comparison of Flow Rate vs. Temperature Rise
Flow Rate (GPM)
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Flow Rate (GPM)
T-K4U Comparison of Flow Rate vs. Temperature Rise
T-D2U Indoor/Outdoor Pressure Loss T-D2U Comparison of Flow Rate vs. Temperature Rise
Flow Rate (GPM)
Set temperature 125°F (52°C) or lower Set temperature 130°F (55°C) or higher Set temperature 125°F (52°C) or lower Set temperature 130°F (55°C) or higher
Head F
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Head F
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