START-UP PROGRAM
Control system
Pump motor
Fan motor
Transformer
(*) Pre-wash valve
Start-up valve
Flame
Lock
(*) oil only
(**) Adjusted by timer 6)(Fig. 2) for oil (6s for gas operations)
MOTOR LOCK: this is brought about by the overload cut-out thermic relay when a phase is missing.
OPERATING PROBLEMS AND CAUSES
The control box is fitted with a disk which rotates during the start up program and can be seen through the release inspection window.
When the burner does not start or stops because of a fault, the symbol which appears in the inspection window indicates the type of
interruption fault.
THE PROGRAMMER DOES NOT START WHEN THE
CONTROL DEVICES CLOSE
• there isn't gas;
• the min. gas pressure switch does not close the con-
tact, it is incorrectly adjusted;
• the max. gas pressure switch does not close the con-
tact with the clamp 1;
• the air pressure switch is set in operating position;
• the control box fuse has blown;
• the cam Pos. 1 selector switch does not close te circuit,
equipment terminals 11 and 8.
HALF AFTER START-UP
• the cam Pos. 2 selector switch does not close the cir-
cuit, at control box terminals 9 and 8.
LOCK HALT
P
the air pressure switch does not effect a selection be-
cause of:
• a faulty contact;
• insufficient air pressure.
➤ If the lock halt takes place between start and pre-start-up without a fault symbol appearing, the fault is usually flame simulation;
➤ The burner continues repeating the start-up cycle without the lock taking place:
A there is oscillation of the min. gas pressure switch
caused by adjustment vary close to the mains pressure,
so that the drop in pressure which occurs at burner start-
up is sufficient to trigger action and thus cause a new
start-up cycle.
B there is oscillation of the max. gas pressure switch
caused by excessive mains pressure (or faulty calibra-
tion) which causes pressure switch intervention when the
valves open, thus causing a new start-up cycle.
2915041
Normal
S7978
Lock for start-up failure
LOCK HALT
malfunctions of the flame detection circuit:
• photo-sensitive cell exhausted;
• fault internal amplifier.
PRE-VENTILATION HALT
the cam Pos. 3 selector switch does not close the circuit,
at control box terminals 10 and 8.
LOCK HALT, NO FLAME SIGNAL
1
• photo-sensitive cell connection to the equipment is in-
terrupted;
• insufficient electrical detection current (min. 70 µA);
• operation of maximal gas pressure switch
LOCK HALT IN OPERATION BECAUSE OF
I
• no flame signal;
• no air pressure;
• operation of maximal gas pressure switch
NOTE:
14
GB
Fig. 21