Takagi T-H3J-DV, Руководство по обслуживанию

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MAINTENANCE
MAINTENANCE
52 • On-Demand Water Heater Service Handbook for 240, 340 & 540 Condensing Models
Burner Removal
and Installation
Tools:
●
#2 Phillips Screw Driver
NOTICE: As you complete the following
steps, reinstall the screws after removing
each component. Doing so will keep the
fasteners organized and will expedite
reassembly.
WARNING
□
Disconnect power to the water
heater by unplugging it from
the wall outlet or turning it
off at the circuit breaker, as
appropriate.
□
Use a non-contact circuit tester
to confirm that power is off
before working on or near any
electrical parts.
□
Ensure that the gas supply is
shut off at the manual gas
shutoff valve.
□
Replace the front cover after
servicing.
□
Failure to follow these warnings
can lead to personal injury or
death.
Burner Removal
1. Prepare the water heater for
service as follows:
1.1 Disconnect power to the
water heater by unplugging
it from the wall outlet or
turning it off at the circuit
breaker, as appropriate.
1.2 Shut off the gas supply at
the gas supply line’s manual
shutoff valve.
1.3 Once the power and gas
have been turned off,
remove the front panel from
the water heater.
INDOOR MODELS: Remove
the Temperature Controller
(item 722, page 71) by
disconnecting its white
connector from the
computer board.
2. Remove the computer board from
the water heater according to the
following steps. (See also Figure
41, p. 49 or Figure 42, p. 50.)
2.1 INDOOR MODELS ONLY:
Unplug the wire connectors
for the exhaust high limit
switch (item 472, p. 74)
and the exhaust thermistor
(item 718, p. 74). See also
Figure 41, page 49.
2.2 Disconnect these wires from
the front of the burner:
•
Flame rod wire (orange).
See Figure 41, p. 49
or Figure 42, p. 50
(center of picture).
•
Air-fuel ratio rod/AFR
wire (yellow).
NOTICE: The connector
is locked onto the spade.
To remove, pinch the flat
surfaces of the connector
while pulling. Do not
pinch the edges or use
a tool.
See Figure 41, p. 49
or Figure 42, p. 50
(center of picture).
•
Igniter rod wire (black).
See Figure 41, p. 49
or Figure 42, p. 50
(center of picture).
2.3 Remove the screw that
secures the computer board
assembly. See Figure 41
(p. 49) OR Figure 42 (p.
50).
Do not remove connectors
from the circuit board.
2.4 Remove the computer board
assembly.
3. Remove both screws which secure
the fuse box to the manifold plate.
Move the fuse box away from the
work area. See Figure 41 (p. 49)
OR Figure 42 (p. 50).
4. Unplug the white connector above
the main gas valve (yellow wires).
This connector is shown just above
the “Main Gas Valve” in Figure 41
(p. 49) and Figure 42 (p. 50).
5. Remove the Gas Valve and
Manifold Plate Assembly:
5.1 Remove the screw that
secures the remaining
ground wire (green) to the
manifold plate.
5.2 Remove the screws that
secure the manifold plate;
doing so will remove the
igniter assembly as well.
NOTICE: Remove only the
screws along the outside
edges of the manifold plate.
See Figure 43.
•
DO NOT remove the
screws securing the
manifold plate to the gas
valve.