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Takagi T-KD20 Technical and Installation Information

Specification data recorded on this site for Takagi T-KD20 Technical and Installation Information.

Install Info Takagi T-KD20 Direct Vent Water Heater

For more detailed information - please download a TKD20 installation manual - (Link at the bottom of this page)

  • Technical Specs of the T-KD20
Power InputNatural. Gas — 20,000-185,000 BTU
LP Gas — 19,000-175,000 BTU
Thermal EfficiencyPropane (max) — 86%
Natural Gas (max) — 85%
Energy FactorPropane — 84%
Natural Gas — 84%
Water PressureMinimum — 15 PSI
Maximum — 150 PSI
Gas Connection3/4"Male NPT
Water Connection3/4"Male NPT
Natural Gas PressureMinimum — 5" WC
Maximum — 10.5" WC
LP Gas PressureMinimum —11" WC
Maximum — 14" WC
Electrical Supply120 Volts / 0.8 Amps
Minimum Flow to Activate3/4 gallons per minute
Flow Rates
(50 degree Input Water Assumed)
90°F rise / 3.4 gallons per minute
80°F rise / 3.9 gallons per minute
70°F rise / 4.4 gallons per minute
60°F rise / 5.2 gallons per minute
55°F rise / 5.8 gallons per minute
50°F rise / 6.2 gallons per minute
Dimensions
(H x W x D)
24 inches by 18 inches by 9 inches
Out Water TemperatureFactory preset at 120 degrees - can be set to 105, 112, 120 or 180 degrees with an internal dipswitch.
Optional Temperature Remote control will allow range from 95 degrees to 180 degrees.
Vent Size Indoor Installation4"
Optional AccessoriesDirect Vent Terminator: TK-TV05
Wall Hanging Kit: TK-WB01
Backflow Preventer: TK-TV03
Temperature Remote Controller
  • Required clearances for OUTDOOR INSTALLATION

Not Allowed for the T-KD20 - Use the AquaStar 240FX or Takagi T-K2 for outside installs in mild climates.

  • Required clearances for INDOOR INSTALLATION
Takagi TKD20INDOOR INSTALLATION
TOP12"
FRONT4" (24" suggested for maintenance space only)
BACK1"
PIPING SIDE6"
NON PIPING SIDE2"
FLOORNon-combustible base
  • Gas & Venting for the Takagi TK2D0 Gas Water Heater

It is very important to have the proper size gas line - see the T-KD20 manual for more detail of pipe size or contact your local gas company or contractor.

Gas5/8"3/4"7/8"1"
Liquid PropaneNot Recommended35 feet70 feet
Natural Gas25 feet80 feet
VentingMin. DiameterMax. Vertical or Horizontal runMax. number of elbowsRule
Direct Vent4 inches (exhaust)
3 Inches (intake)
25 feet3Deduct 5ft. for each elbow from max. vent length
  • Dimensions of the Takagi TKD20
HeightWidthDepthWeight
24.5"16.5"8.3"65 lbs.(shipping weight)
  • Combustion Air and Ventilation Takagi TKD20

Please Note The T-KD20 must be connected to a Category III gas vent for discharge pipe in order to direct the dangerous exhaust byproducts to the outdoors. Connect the 4” Category III vent pipe to the minimum 2” round collar on through the outside wall. This water heater must be vented in accordance with the section on venting of equipment in the latest edition of the National Fuel Gas Code. This is a Category III appliance, and must be vented accordingly. The following are UL listed or CSA certified manufacturer: ProTech Systems FasNSeal Stainless Steel Venting. This unit requires 4” vent pipe. Connect the vent pipe to the unit so that it is sealed airtight. Follow the vent pipe manufacturer’s instructions when installing the vent pipe. Do not common vent this appliance with any other vented appliance. The venting system must not exceed a length of 25 ft. minus 5 ft. for every elbow. Do not use more than 3 elbows. If the horizontal vent run exceeds 5 ft., the following criteria must be observed

  • There must be a 1 ft. vertical run off the top of the heater before the horizontal run begins
  • The horizontal run must be supported at 3 foot intervals
  • The vent run should be pitched up towards the termination at ¼” per foot
  • The unit should be vented out to directly through a wall
  • Combustible Air Supply

The T-KD20 is direct vent (Sealed Combustion) system that all combustible air supplies from outside building. The T-KD20 must be installed in a location where the proper amount of combustible air will be available to it at all times without obstructions. As combustible air supply pipe can be used suitable 3” pipe such as Galvanized single wall vent pipe, ABS 3”, colligate stainless steel pipe and category III stainless steel pipe supply air pipe.

  • Output Temperature Ratings of the. Takagi TKD20

The T-KD20 is factory preset at 120 degrees. You can change the output temperature with the internal dipswitches to 105 degrees, 112 degrees, 120 degrees or 180 degrees. If you want to use any other temperatures that this - you can purchase the optional Remote Control Temperature that will allow the T-KD20 to have output temperatures from 95 degrees to 180 degrees. Please Note Hot Water Heater Temperature over 125 Degrees F can cause severe burns instantly or death from scalding. Children, disabled and elderly are at the highest risk of being scaled. Feel water temperature before bathing of showering.