Operating instructions

6.3 Operational Failure Symptoms via Fault/Flash Code
The following table lists the possible faults which can be read by
flashing code or read directly off of an appropriate timer or with the
PC diagnostics kit.
Failure Symptom Probable Cause Check and Correct
1X Flash (F 01)
No combustion after completion of
start up sequence.
- Fuel system
- Combustion air
- Electronic ignition
- Fuel level
- Type of fuel being used
- Fuel filter
- Fuel line connections (air bubbles in
fuel lines)
- fuel nozzle plugged
- Air intake or exhaust, restricted or
plugged
- incorrect electrode gap
2X Flashes (F 02)
Flame out during burner operation
no restart possible
- Fuel supply (shortage of fuel) - Restriction in the fuel system
- Fuel filter
- Fuel line connections (air bubbles in
fuel lines)
- Type of fuel being used
3X Flashes (F 03)
Low voltage for more than
20 seconds
- Electrical system - Load test batteries
- Corrosion at connections
- Loose connections
4X Flashes (F 04)
Flame detector recognizes false
flame signal during pre-start or
shut-down cycle
- Defective flame detector - Replace flame detector
5X Flashes (F 05)
Flame detector
- Wiring
- Defective flame detector
- Damaged wiring, open or short circuit
- Replace flame detector
6X Flashes (F 06)
Temperature sensor
- Wiring
- Defective temperature sensor
- Damaged wiring, open or short circuit
- Replace temperature detector
7X Flashes (F 07)
Fuel solenoid valve
- Wiring
- Defective solenoid valve
- Damaged or corroded wiring, open
or short circuit
- Replace solenoid valve
8X Flashes (F 08)
Combustion air fan motor
- Wiring
- Wrong RPM
- Defective combustion air fan motor
- Damaged wiring, open or short circuit
- Replace combustion air fan
- Replace combustion air fan
9X Flashes (F 09)
Circulation pump motor
- Wiring
- Defective circulation pump motor
- Damaged wiring, open or short circuit
- Replace circulation pump motor
10X Flashes (F 10)
Temperature limiter
- Overheat condition
- Coolant flow
- Wiring
- Defective temperature limiter
- Reset temperature limiter
- Coolant level or flow restriction
- Air trapped in coolant circuit
- Damaged or corroded wiring, open
or short circuit
- Replace temperature limiter
11X Flashes (F 11)
Electronic ignition coil
- Wiring
- Defective electronic ignition coil
-Damaged wiring, open or short circuit
-Replace electronic ignition coil
12X Flashes (F 12)
Heater lock out
3 repeated faults/flame-outs or
5 repeated start attempts
Reinitialize control unit by switching
heater on and disconnecting power.
Table 601: Operational Failure Symptoms (Control Unit SG 1572 D)
Thermo 230/300 6 Basic Troubleshooting
603