A.O. Smith GWV - 120, Installation And Service Manual

Page: 81 / 102

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Instruction manual GWV 81
Code + description Cause Measures to take Comment
F06 (blocking error)
Short circuit between
flame probe and earth
Damaged cable in
contact with metal
surface.
Check the wiring of the flame probe. Replace the wiring if
necessary..
If the error persists, contact your installation engineer.
To replace the necessary parts, you must contact your installation
engineer.
Ceramic part of the
flame probe is
broken/cracked.
1. Check that the ceramic part of the flame probe is still intact in
the vicinity of the burner's air distribution plate.
2. If not, the flame probe must be replaced.
F07 (lock out error)
A flame has been
detected after the gas
valve was closed.
Defective gas valves 1. Check whether there is still burner pressure present after the
gas valves have closed.
2. Check whether a flame is still present after the gas valves have
closed.
3. If this is the case, the gas control must be replaced.
If the error cannot be resolved or is persistent, contact your
installation engineer
To replace the necessary parts, you must contact your installation
engineer
F08 (lock out error)
Error message from
safety relay
Flame detection before
the gas valve opened.
1. Reset electronic controller.
2. If the error appears again, replace the electronic controller.
3. If this is the case, the gas control must be replaced. If the error cannot be resolved or is persistent, contact your
installation engineer
To replace the necessary parts, you must contact your installation
engineer
F09 (lock out error)
Water temperature
safety.
Temperature T
1
, T
2
or
T
3
is greater than 99
o
C.
1. Check that the system pump is functioning.
2. Check the position of the temperature sensor T
1
., T
2
and T
3
.
3. Reset appliance controller
Error F09 remains active in the event that the water temperature
during a reset was higher than 90
o
C. If this is the case, first draw
water off by opening the nearest hot water tap, so that cold water
can flow in.
If the error cannot be resolved or is persistent, contact your
installation engineer