A.O. Smith Innovo IR 12-160, Installation, User And Service Manual

Page: 77 / 96

Code and description Cause Measure
F04
(lock out error)
Ignition error
Three unsuccessful
ignition attempts.
No gas. - Make sure that the main gas supply
valve is open. If necessary, open the
valve.
- Make sure that the manual gas supply
valve, before the gas control valve, is
open. If necessary, open the valve.
- Make sure that the gas supply
pressure to the gas control valve is
correct, refer to Gas supply pressure
(see 8.9.3).
Air in the gas pipes. - Bleed the air out of the gas pipe.
- Make sure that the gas supply
pressure to the gas control valve is
correct, refer to Gas supply pressure
(see 8.9.3).
Defect in the hot surface igniter circuit. - Make sure that the hot surface igniter
is installed correctly.
- Make sure that the wiring of the hot
surface igniter is not damaged.
- Measure the resistance across the hot
surface igniter. This must be between
the 36 and 72 Ohm (at room
temperature).
- Make sure that the hot surface igniter
lights up during ignition.
If necessary, replace the hot surface igniter.
Defect in the ionisation circuit. - Make sure that the flame probe is
installed correctly.
- Make sure that the wiring of the flame
probe is not damaged.
- Measure the ionisation current. This
current must be a minimum of 3 μA
(parameter
109
).
If necessary, replace the wiring and/or
flame probe.
Supply voltage too low. - Make sure that the supply voltage on
the controller is correct.
- If the supply voltage is below the
stated tolerance and the error
persists, contact your maintenance
and service engineer.
- Install an isolating transformer.
Bent flame probe is in contact with
metal surface. - Make sure that the flame probe is not
bend.
- If necessary, replace flame probe.
Ceramic part, of the flame probe, is
broken or cracked. - Make sure that the ceramic part of the
flame probe is not broken or cracked
in the vicinity of the burner.
- If necessary, replace flame probe.
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