baltur COMIST 20 Installation, Use And Maintenance Instruction Manual page 59

UV PHOTOCELL
Even the slightest greasiness will compromise the passage of the
ultraviolet rays through the UV photocell bulb, thus preventing the
sensitive internal element from receiving the quantity of radiation
necessary for it to work properly. If the bulb is fouled with diesel, fuel
oil, etc... it must be properly cleaned.
CAUTION / WARNING
Even by simply touching the bulb with fingers, it is possible
to leave a slight greasiness which could compromise UV
photocell operation.
The UV photocell does not detect daylight or the light from a common
lamp.
Its sensitivity can be tested using a lighter or candle flame.
To ensure proper operation, the UV photocell current value should
be sufficiently stable and should not drop below the minimum value
required by the specific equipment; this value is indicated in the wiring
diagram.
It may be necessary to search for the best position by sliding (axial
or rotational movement) the casing that contains the photocell with
respect to the fastening clamp.
This can be checked by connecting a micro-ammeter, with a suitable
scale, in series to one of the two UV photocell connection cables.
Obviously the + and - polarity must be respected.
The photocell current value required for a correct operation of the
control box is indicated in the wiring diagram.
Verify the flame detector operation as follows:
• Disconnect the wire coming from the ionisation electrode;
• Start up the burner;
• The control box will complete the control cycle and after two
seconds will lock the burner due to the lack of ignition flame;
• switch off the burner;
• Re-connect the wire to the ionisation electrode.
• This test should also be conducted with the burner already on;
when extracting the photocell from its seat, the apparatus should
shut down immediately.
DIAGRAM FOR REGULATION OF COMBUSTION HEAD AND
ELECTRODE DISK DISTANCE
21 / 36
0006080872_201711
2
9,5
4
8,5
ENGLISH