Operation Lights - Biasi M110.24SM/E Service Manual

with the signal given by the control panel through the
adjustment made by the user (knob
Fig. 9.4
Normally, the result of the comparison between these
two signals directly operates the fan speed adjusting
the useful output generated in order to stabilize the
temperature of the exiting water.
If during the d.h.w. mode operation, the temperature of
the primary circuit goes over 90°C, the useful output is
automatically reduced so that the primary circuit can-
not reach excessive temperatures.
The control sequences in
tion are illustrated in detail in sections 9.10 and 9.11.
9.4

Operation lights

The Electronic control/ignition p.c.b. is provided with
three lamps (L.E.D. indicators) 18 in Fig. 9.2 that give
optical information during the operation of the boiler.
The green lamp on the left gives information whether
the boiler is in stand---by mode or during the normal
operation of the boiler.
The following table gives the relationship between the
lamps indication and their meaning.
).
90 ˚C
function and in
A short pulse every 4 seconds
1 second ON 1 second OFF
With the boiler switched ON (
(18 in Fig. 9.2) are activated.
The following table gives the relationship between each
of the possible lamp combinations and their meaning.
func-
Lamp Lamp
OFF ON
* These conditions are normal only for a short time when the
power supply is applied to the boiler.
If permanent they indicate a faulty p.c.b.
Electronic control/ignition p.c.b.
Boiler in stand --- by condition.
(function control in
position).
Anti--- freeze system active.
Boiler ON condition
(function control in
position)
or
Normally operating boiler
(see the previous table for details)
C.h. operation
D.h.w. operation
Frost protect operation
D.h.w. operation
Excessive temperature on primary circuit
Faulty c.h. temperature probe NTC
Faulty d.h.w temperature probe NTC
Faulty flue temperature probe NTC
Faulty external temperature probe NTC
Faulty primary circuit
(no water or absence of flow)
Lack of burner ignition
Safety thermostat lock out
Faulty fan control system
Flue temperature probe NTC lock out
Flame detection error
Lack of power supply or faulty electronic
control p.c.b.
Faulty Electronic control/ignition p.c.b.. *
Flashing lamp, alone
or simultaneously
with an other lamp.
or
) all the lamps
Flashing lamp,
alternate with
another lamp.
17