Takagi T-K3 User Manual

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FLOW
• The flow rate through the FLASH T-K3/T-K3-Pro is limited to a maximum of 7.0 GPM.
• The temperature setting, along with the supply temperature of the water will determine the
flow rate output of the unit.
• Please refer to the temperature vs. gallons per minute chart on p. 46 to determine the likely
flow rates based on your local ground water temperature and your desired outlet water
temperature combination.
• Based on the United States Department of
Energy method of testing water heater output,
the T-K3/T-K3-Pro is rated for 252 gallons per
hour (GPH) or 4.2 gallons per minute (GPM)
for Natural Gas, and 264 GPH or 4.4 GPM for
Liquid Propane, when raising the water
temperature by 77°F (from 58°F to 135°F).
• Refer to the chart to the right for typical
household plumbing fixture flow rates to
determine what the FLASH T-K3/T-K3-Pro can
do in a household application.
FREEZE PROTECTION SYSTEM
• This unit comes equipped with heating blocks to protect it against damages associated with
freezing.
• For this freeze protection system to operate there has to be electrical power to the unit.
Damage to the heat exchanger caused by freezing temperatures due to power loss is not
covered under the warranty. In cases where power losses can occur, consider the use of a
backup power supply.
• The freeze protection system will activate when the surrounding and/or outside temperatures
drop below 36.5°F (2.5°C).
• In any areas subject to freezing temperatures, Takagi highly recommends installing the unit
indoors. In such an installation, freezing issues can only occur if cold air enters through the
venting into the heat exchanger, whether by negative pressures within the installation
location or by strong outside winds. It is the installer’s responsibility to be aware of these
issues and take all preventative measures. Takagi will not be responsible for any damage to
the heat exchanger as a result of freezing.
• Takagi also highly recommends the use of a back flow vent damper and/or converting the T-
K3/T-K3-Pro to a direct-vent unit to minimize the amount of cold air entering through the
exhaust venting when the water heater is off.
• If you will not be using your heater for a long period of time:
1. Completely drain the unit of water. Refer to p. 31.
2. Disconnect power to your heater.
This will keep your unit from freezing and being damaged.
CAUTION: Only pipes within the water heater are protected by the freeze protection
system. Any water pipes (hot or cold) located outside the unit will not be protected.
Properly protect and insulate these pipes from freezing.
Household Flow Rates
Appliance / Use Flow Rate (GPM)
Lavatory Faucet 1.0
Bath Tub 4.0 – 10.0
Shower 2.0
Kitchen Sink 1.5
Dishwasher 1.5
Washing Machine 4.0
Taken from UPC 2006

Takagi T-K3 Specifications

General

Type	Tankless
Installation Type	Indoor
Maximum BTU Input	199, 000 BTU/h
Gas Connection Size	3/4"
Vent Size	3"
Hot Water Flow Rate (at 35°C rise)	6.6 GPM
Maximum Input	199, 000 BTU/h