Product Overview

Tankless Water Heaters
Residential / Commercial Gas
SUGGESTED SPECIFICATION FOR THE T-D2U-IN OR T-D2U-OS
The fully modulating, on-demand, gas red tankless water heater shall be Takag Tankless Water Heater model T-D2U-IN or T-D2U-
OS having a maximum input rating of 199,000 Btu/h and available in NG. The heater shall have ¾ in. male NPT water and gas
connections. The inlet gas supply pressures shall be 5.0 in. WC (min.) up to 10.5 in. WC (max) for NG. The heater shall be supplied
with a temperature remote, 9009069005, that can be installed up to 400 ft. from the heater using 20 gauge (minimum) control wire. The
temperature remote shall provide diagnostic information, fault history, and heater set temperature. The heater shall operate using 120 V
/ 60 Hz power source. The indoor heater will incorporate a factory installed power cord.
The indoor heater shall be vented with 4” diameter Category III vent pipe with a length not to exceed 50 ft. (equivalent), terminating
horizontally or vertically. The indoor heater can be direct vented with optional direct vent conversion kit, 9007667005, using 3”
diameter intake air pipe. The intake pipe may use material such as PVC, ABS, aluminum, or Category III pipe and cannot exceed 50 ft.
(equivalent) length. The outdoor heater shall be constructed with an integral exhaust vent on the front of the heater.
The water heater shall use a commercial grade copper alloy, n tube heat exchanger with quick release brass or bronze waterways.
The heater shall be controlled by an onboard solid-state printed circuit board which uses the following factory installed components:
thermistors to monitor inlet and outlet water temperature; a ow sensor to measure ow rate; a ame sensor to monitor combustion;
an Air-Fuel Ratio Rod to measure and adjust operation in order to maintain optimal combustion efciency. The heater also consists of
inline fusing and surge absorbers for electrical surge protection, an electronic spark igniter, a hi-limit temperature switch, modulating
gas valve, an overheat cutoff fuse, ceramic heating blocks to protect the heat exchanger and water piping. The indoor heater shall
incorporate auto-re system for additional freeze protection.
The heater can manifold to Easy-Link up to 4 heaters to provide additional capacity. The Easy-Link controls shall be built onto the
onboard solid-state printed circuit board and does not require external controls. The linking control wire shall be supplied with the
heater. The heaters can use a Multi-Unit controller, 9008300005, to manifold 5-20 heaters. The Easy-Link and Multi-Unit Controller
shall modulate the system for the most efcient performance. The Easy-Link and Multi-Unit Controller shall rotate the priority heater
every 12 hours of operation time or 100 starts for balanced duty/cycle operation.
The heater shall be design certied by CSA according to ANSI Z21.10.3, approved for sale in the United States with a minimum energy
factor of 0.82, meets the energy efciency requirements of the U. S. Department of Energy and ASHRAE 90.1, complies with SCAQMD
Rule 1146.2 and other air quality districts with similar requirements for low NOx emissions of 14 ng/J or 20 ppm, and shall be certied
by NSF to NSF/ANSI 5 Standard.
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TBGSS01212
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