2736
12
N.B.: If problems still occur after all of the above checks have been made, check the electrical connections
on the plug and sockets, the damper and burner motor, gas control wiring ignition transformer and
external interlocks, if the burner still fails to function, replace the control box.
7 blinks The burner goes
into lockout imme-
diately following the
appearance of the
flame
The operation solenoid lets little gas
through
Increase
Ionisation probe incorrectly adjusted Adjust
Insufficient ionisation (less than 5 A) Check probe position
Earth probe Withdraw or replace cable
Burner poorly grounded Check grounding
Phase and neutral connections inverted Invert them
Defective flame detection circuit Replace the control box
Burner goes into
lockout during ope-
ration
Probe or ionisation cable grounded Replace worn parts
10 blinks The burner does not
switch on, and the
lockout appears
Incorrect electrical wiring Check
The burner goes
into lockout
Defective control box Replace
Presence of electromagnetic
disturbances in the thermostat lines
Filter or eliminate
No blink The burner does not
start
No electrical power supply Close all switches - Check con-
nections
A limiter or safety control device is open Adjust or replace
Line fuse blocked Replace
Defective control box Replace
No gas supply Open the manual valves betwe-
en contactor and train
Mains gas pressure insufficient Contact your GAS COMPANY
Minimum gas pressure switch fails to
close
Adjust or replace
The burner conti-
nues to repeat the
start-up cycle,
without lockout
The gas pressure in the gas mains lies
very close to the value to which the mini-
mum gas pressure switch has been set.
The sudden drop in pressure after valve
opening causes temporary opening of the
pressure switch itself, the valve immedia-
tely closes and the burner comes to a halt.
Pressure increases again, the pressure
switch closes again and the ignition cycle
is repeated. And so on
Reduce the minimum gas pres-
sure switch intervention pres-
sure. Replace the gas filter
cartridge.
Ignition with pulsa-
tions
Poorly adjusted head Adjust
Ignition electrode incorrectly adjusted Adjust
Incorrectly adjusted fan air damper: too
much air
Adjust
Output during ignition phase is too high Reduce
Signal Problem Possible cause Recommended remedy