TM 10-4520-259-13&P
TEST
a.
Turn on water heater fuel and power.
b.
Wait approximately 20 seconds. If audible alarm sounds, go to step i. If blower motor does not come
on and ignition does not occur, proceed to next step.
c.
Open control box lid (1) and check motor contactors (2). If contactors are tripped, reset contactors and
check for normal operation. If contactors continue to trip, test motor contactor operation as described in step d.
If contactors are not tripped, proceed to step e.
CAUTION
Ensure that power is off before making continuity check. Damage to test
equipment could result.
NOTE
Isolate any electrical components before starting continuity check.
d.
Using the multimeter, check continuity from input terminals to output terminals
on motor contactor solenoid (3). Meter should indicate an open circuit at each set
of terminals. Push up on motor contactor solenoid. Meter should indicate
continuity at each set of terminals. Check continuity of relay coil. Multimeter
should indicate low resistance. If it registers infinity or 0 ohms, replace contactor.
e.
Loosen screw (4) on cover (5) and remove cover (5) from flame safeguard control (6) exposing control.
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