Takagi Flash Water Heater T-KD20, Installation Manual And Owner'S Manual

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Operation
General
The Flash Water Heater is an instantaneous,
tankless water heater designed to efficiently supply
domestic or commercial hot water and space
heating applications. The principle behind the
Flash water heater is simple: Once a hot water tap
is opened, the Flash’s flow sensor detects that hot
water is needed, and automatically commands the
computer to electronically ignite the burners, and
heat water. During operation, the computer
monitors the water temperature and flow rate, and
controls the gas flow and fan speed to maintain a
constant output temperature. After the burners are
ignited the “fire on” lamp will be lit.
0.75 gallons per minute is required to turn the
burner on, but after the burner is ignited, the flow
rate can drop to 0.6 gallons per minute without the
burner turning off.
As long as water, gas and electricity are
connected, there will be an endless flow of hot
water. To turn on your water heater, just open a
tap. To turn the heater off, just close the tap.
Turning It On
To turn on the Flash water heater
1. Open a hot water tap, or turn on water
demanding appliance.
2. Unit will detect flow, burners will ignite, and
“Fire On” lamp will light up.
3. If necessary, mix in cold water to get a
comfortable temperature.
Turning It Off
To turn off the Flash water heater
1. Close the hot water tap, or turn appliance off.
2. Flow will diminish, unit will shut off.
3. “Fire On” lamp will go out.
Temperature
The output temperature of the T-KD20 has been
factory set for a maximum 120
°
F (50
°
C). This is
electronically controlled by the computer and can
be adjusted with a TK-RE01 temperature
controller, or with the dipswitches on the computer
board (See pgs. 21-22 for dipswitch settings).
Further adjustment may be made by mixing in cold
water with the hot to obtain the ideal water
temperature.
The flow rate possible out of the unit is dependent
on the temperature setting chosen. Consult the
flow charts on the last page of this unit to
determine the possible outlet temperature and flow
rate combinations.
WARNING: Temperatures above 125º F (52º C)
can cause severe burns or death from scalding.
Children, the disabled and the elderly are at a high
risk of being injured. Feel the water temperature
before bathing or showering. Do not leave
children, disabled persons, or the elderly
unsupervised.
Flow
The flow rate through the T-KD20 is limited to a
maximum of 6.9 GPM. The temperature setting,
along with the supply temperature of the water will
determine the flow rate the unit puts out. Consult
the flow charts on the last page of this manual to
determine the possible outlet temperature and flow
rate combinations. Based on the United States