MANCANZA FIAMMA /NO FLAME
(E140901X) 28 di/of 33
5.
ELECTRIC CHECKS
5.a MCA
The ignition control unit is connected directly to the valve. The control unit is autonomous in the control of the
spark ignition, maintenance and verification of the gas presence inside the burner.
When the machine is in stand-by mode the gas ignition unit is turned off completely and it is not possible to
apply any control or reset operations. With the gas controller switched off no alarm
“NO FLAME” can be
detected.
While the machine is in operation and in heating demand, the control unit is turned on by a signal at 230V~
supplied by the electronic card IM7. The control unit proceeds to activate the following sequence:
- Opening of the valve by means of excitation of the two coils. At this juncture you hear a hissing
sound coming from the nozzles, caused by the passage of gas;
- After a second is activated the discharge of the spark plug. At this juncture it is audible a very rapid
sequence of electrical discharges between the pole "hot" spark plug and ground wire;
- The burner will light up (except for the problems listed in the previous chapters);
- The ionization sensor detects the presence of the flame and the consent to the control unit to keep
lit the valves up to the disappearance of the signal of the heating temperature reached.
It’s not possible to interact with the control or change the power-up sequence.
It is not possible to verify if the coils of the valves are electrically supplied from the gas ignition unit.
Vice versa,
it’s possible to check the integrity of the valves by controlling the impedance of the coils as
shown below. The terminals are visible by removing the control unit from the valve body.
The ignition of the heating unit is made by selecting a program with a temperature higher than the one
detected by the temperature probe. The signal at 230V~ comes directly from the control board IM7. The
neutral and the earth conductor are not dissected. Following the wiring diagram.