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

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6. Turn the manual gas control valve located on
the outside of the unit clockwise to the ON
position.
7. Turn on the electrical power to the appliance.
8. Turn on any tap, and the T-KD20 will initiate
itself.
9. If the appliance will not operate, follow the
instructions in the “Turning Off the Gas Supply
to the Appliance” section following, and call a
service technician or gas supplier.
TURNING OFF THE GAS SUPPLY TO THE
APPLIANCE
Close the manual valve on the gas inlet line. Turn
off the power supply.
Manifold pressure tap
Maintenance
WARNING: Turn off the electrical power
supply, the manual gas control valve, and the
manual water control valve before servicing.
The unit should be checked once a year or as
necessary by a certified and trained technician. If
repairs are needed, a certified and trained
technician should do the repairs.
The following systems and parts should be
checked at least once a year:
1. Venting systems
2. Burners
3. Manual operation of the pressure relief valve to
ensure correct operation.
4. Periodic cleaning of the water filter, refer to
figure below.
5. Heat exchanger. Remove the thermistor and
check for a mineral coating. A mineral coating
on the thermistor requires flushing the heat
exchanger with a descaling solution. Scale
build up will void your warranty and shorten the
life of your water heater.
Troubleshooting
Water Isn’t Hot Enough
The T-KD20 can burn gas at a maximum input rate
of 185,000 BTUH. This puts a limit on the possible
output temperature and flow capabilities (See flow
chart on the last page of this manual). If the water
doesn’t seem hot enough, compare the flow and
temperature that is being attained to the T-KD20
flow vs. temperature chart. If the unit is not
performing according to the chart, first check that
the gas supply line is sized properly, and that the
gas pressure is within the required range. If the
gas line is fine, check the plumbing for mixing
valves, thermostatic valves, scald protection,
single handled valves or crossed connections. If
the unit is performing in accordance with the flow
chart, then it may be undersized for the
application. If the unit is performing according to
the chart, the output temperature can be adjusted
using the TK-RE01 or with the dipswitches on the
unit (See pgs. 22-23)
It Takes Too Long to Get Hot Water
The T-KD20 takes three seconds to ignite, and
three more to get up to temperature. The rest of
the time needed for hot water to get to a fixture is
due to the length of piping between the water
heater and the fixture. If the unit seems to be
taking longer than six seconds to initiate, check the
filter and flow sensor for any debris or damage.