Takagi T-H3J-DV Service Handbook

MAINTENANCE
MAINTENANCE
On-Demand Water Heater Service Handbook for 240, 340 & 540 Condensing Models • 61
4.1 Open the clip that secures
the yellow wires to the
boom, le-hand side of the
cabinet. Remove the wires.
See Figure 52.
4.2 Remove both screws that
secure the fuse box and li
the fuse box away. (It will
sll be connected to wires.)
4.3 Unlatch the connectors on
the freeze protecon heater
wires. There are 5 sets of
these white connectors with
yellow wires (one above
the fuse box assembly,
three below the fuse box
assembly, and one near the
boom, right-hand side of
the cabinet).
INDOOR MODELS ONLY:
The plug on the back of
the fuse box connects it
to the freeze protecon
thermostat. This thermostat
hangs o of the intake vent
(top, le of cabinet). Leave
that thermostat in place.
(See Figure 53.)
When you are finished, the
plug, wire, and fuse box will
hang from the intake vent.)
5. 
valve (item 402, page 74) as
described in the following steps.

5.1 Remove fasteners 16A and
14-22 (items 460 and 461,
page 74).
NOTICE: If you have a 540
model with a bypass valve,
you must remove an
addional fastener. See item
458 at connecon point
A
(two places), page 74.
5.2 Pull the cold connecon
tube (item 466, page 74)
from the outlet of the ow
sensor/control valve.
Example:
Freeze Protection Heaters
with Clips
Figure 54.
NOTICE: If you have a 540
model, you must pull a
poron of the tube out of
the bypass valve as well.
5.3 Turn the ow sensor/control
valve gently and li it o of
the inlet.
6. 
(item 466, page 74) as follows:
6.1 Disconnect fastener 16-
25 (item 462, page 74)
from the top of the cold
connecon tube.
6.2 Remove two heaters and
clips (located at the top
and boom of the cold
connecon tube):
◦ Items 414 & 451, p. 74.
◦ Items 415 & 451, p. 74.
See also Figure 54.
6.3 Remove the cold connecon
tube from the heat exchanger.
6.4 Remove the cold connecon
tube from the cabinet.
7. Remove the igniter assembly:
See
following sub-steps.
7.1 Remove the screw that
secures the igniter assembly.
7.2 Disconnect the igniter
wire at the igniter rod wire
connecon.
8. Disconnect the blue wires from
the high limit switch. See “High
Limit Switch (Heat Exchanger),”

Indoor Models:
Freeze Protection Thermostat
Hangs from Air Intake Vent.
Figure 53.

Takagi T-H3J-DV Specifications

General

Brand	Takagi
Model	T-H3J-DV
Category	Water Heater
Language	English