Takagi T-H3J-DV Service Handbook page 58

6.4 Secure the gas valve to the
inlet by installing the brass
screw through both tabs at
the connection (hand-tight
only).
See Figure 41 (p. 49) or
Figure 42 (p. 50).
6.5 Attach the air tube from the
bottom of the combustion
chamber to the port on the
left side of the gas valve.
(See Figure 49, page 57.)
7. Reconnect the plug and receptacle
that you disconnected earlier (i.e.,
the ones with the yellow wires).
This connector is shown just above
the "Main Gas Valve" in Figure 41
(p. 49) and Figure 42 (p. 50).
8. Install the fuse box assembly to
the left side of the manifold plate.
(See Figure 41 (p. 49) or Figure
42 (p. 50).)
Hand tighten two screws to secure
it to the manifold plate.
9. Install the computer board (PCB):
9.1 Position the PCB in place:
Small feet at the
bottom must fit into the
corresponding holes in the
case.
9.2 Insert and hand tighten the
screw at the top of the PCB
to secure it to the fuse box.
10. Verify that all manifold screws
have been reinstalled and hand
tightened.
58 • On-Demand Water Heater Service Handbook for 240, 340 & 540 Condensing Models
11. Complete the wiring:
Refer to Figure 41 (p. 49) or
Figure 42 (p. 50) as you complete
these steps.
•
Install the green ground wire
onto the manifold plate.
(See "Ground Connection" in the
figure noted above.)
•
Insert the connector from the
power supply cable to its port on
the fuse box. (See "Fuse Box" in
the figure noted above.)
•
Reinstall the flame rod/AFR
wires.
(See "Flame Rod & AFR Wire
Connections" in the figure noted
above.)
12. INDOOR MODELS: Connect the
wires from the temperature
controller (item 722, page 71) to
the computer board.
The correct receptacle for your
model is shown in one of these
schematics:
•
240 (T-H3J) and 340 (T-H3s)
Models. Page 30.
Solenoid Connector
(locations vary)
Stamped Numbered
Number
In each case, these numbers
must match.
Connectors have no polarity.
Figure 50.
See "Temperature Controller"
•
540 (T-H3) Models. Page 31.
See "Temperature Controller."
13. Verify that all gas and water
connections are tight and that
there are no parts left over.
Be sure that you reconnected the
condensate tube at the bottom,
right-hand corner of the cabinet.
14. Slowly open the gas valve and
check for leaks. If any gas leaks
appear, shut off the gas and turn
off power to the heater.
WARNING! Failure to prevent gas
leaks can result in an explosion,
severe injury, or death.
15. Turn on water to the heater and
test for proper operation.
16. Verify that there are no water or
gas leaks.
17. Outdoor models:
Reinstall the front cover.
INDOOR MODELS:
Insert the temperature controller
into the opening of the front cover,
then reinstall the front cover.
If there are any questions, please
contact technical support.
Wire