Spheros Thermo E 320 - Error Symptom Extraneous Light Detected Prior to Ignition or During Purge Cycle

5 Troubleshooting and error correction Thermo E 200 / 320
508
5.4.4 Error symptom "Extraneous light
detected prior to ignition or during purge
cycle"
NO
YES
Did overheating occur due to impaired
coolant flow?
Open valves, refill coolant, bleed coolant circuit.
Verify the circulating pump is correct controlled.
Is the burner properly screwed onto the
heat exchanger?
Properly screw burner onto the heat
exchanger.
Did the heater burn longer before?
Was the heater stopped or the voltage
disconnected before or during purge
cycle?
Is the combustion air intake clean/free?
Is the motor OK and can rotate freely?
Is the exhaust outlet clean/free?
Is the burner pipe coked, contaminated
or damaged?
Is the heat exchanger sooted?
Is the correct combustion chamber in-
stalled?
Clean/clear combustion air intake.
Correct motor problem.
Clean/clear exhaust outlet.
Clean / replace burner pipe.
Clean heat exchanger.
Insert correct combustion cham-
ber.
Did the error return?
Let heater cool down for approx. 2
minutes and restart it again.
Did the error return?
Replace the complete solenoid valve.
Did the error return?
Control unit defective, replace it.