Takagi T-H3J-DV Service Handbook page 62

Flame Rod Wire Connector:
To remove, pinch at sides at end
with your nger nails, then slide
connector o the spade.
Figure 55.
Manifold Screws:
• DO NOT remove the screws
indicated by the white,
crossed-out circles.
• Remove the screws
indicated by the white
arrows.
Figure 56.
Gas Valve
Port
Air Tube
Figure 57.
62 • On-Demand Water Heater Service Handbook for 240, 340 & 540 Condensing Models
The wires are locked onto the
connectors. Pinch the flat sides on
each connector to release it.
9. Remove the Gas Valve and
Manifold Plate Assembly:
9.1 Unplug wire connectors from
the air/fuel ratio rod (AFR),
flame rod, and igniter.
See Figure 55.
9.2 Remove the screws that
secure the green ground
wires to the manifold plate.
(You may have completed
this step already.)
9.3 Remove the screws that
secure the manifold plate.
(See page 49 or 50).
NOTICE: Remove only the
screws along the outside
edges of the manifold plate.
See Figure 56.
•
DO NOT remove the screws
securing the manifold plate
to the gas valve.
•
DO NOT remove the
screws along the interior
of the manifold plate.
•
You will not be able to
pull the manifold plate
away from the assembly
yet. That will happen
during gas valve removal.
9.4 INDOOR MODELS: Remove
the clip that secures the
power cord. See "Power
Cord Mounting Tab" in
Figure 41, p. 49.
9.5 Disconnect the air tube off
the left side of the gas valve
(Figure 57.) See also "Clear
Plastic Tube" in Figure 41, p.
49.
9.6 Disconnect the connector
on the left side (blue wires)
which goes to the overheat
cutoff fuse. See "Connector
for Overheat Cutoff Fuse
(Blue Wires)" in Figure 41, p.
49.).
9.7 Remove the brass screw
securing the gas valve to the
gas connection. The screw is
located at the bottom, right-
hand side of the gas valve.
See "Brass Screw Securing
Gas Valve..." on page 49
or 50.
9.8 Lift the manifold plate/
gas valve assembly upward
to remove it from the gas
inlet connection. (The gas
valve and manifold are still
connected together.)
You may need to twist the
gas valve/manifold assembly
slightly.
9.9 Unplug the wire connectors
from the solenoid valves,
main gas valve, and
proportional gas valve.
(These valves are connected
to the back corner of the
manifold plate.) There are
five connectors that can
be unplugged from the
manifold plate assembly.
9.10 Inspect the gaskets on
the manifold plate for any
tears. If compromised,
replace with part number
100074229 (item 113) and/
or 100074230 (item 114).
See p. 73.