24
SAFETY CHECKS
After adjusting, always check the following:
1)
Burner stop: open air and gas thermostats and pressure switches.
2)
“Blocking”: shadow the photocell (UV).
To unblock, push the appropriate button.
MAINTENANCE
At the end of the heating season, it is good practice to clean the gas and light oil filters, the combustion head (disk,
insulators, nozzles), the combustion air passages and the photoelectric cell (UV).
It is advisable to use wooden or plastic instruments to clean the nozzle passages.
Nozzle should be replaced after 12 months’ use.
UV CELL
If flame detection is carried out with the UV cell, the following should be taken into consideration.
Even the slightest greasiness will compromise the passage of the ultraviolet rays through the UV photoelectric cell bulb,
thus preventing the sensitive internal element from receiving the quantity of radiation necessary for it to function properly.
Should the bulb be fouled by light oil, fuel oil, etc., it is indispensable to clean it thoroughly.
It should be pointed out that even by simply touching the bulb with the fingers, it is possible to leave a slight greasiness
which could compromise the working of the UV photoelectric cell.
The UV cell does not “see” daylight or light from an ordinary lamp.
It is possible to verify its sensibility with a flame (or cigarette lighter or a candle) or with the electric spark that occurs
between electrodes in an ordinary ignition transformer.
To ensure that the UV cell works properly, its current value should be sufficiently stable so as not to fall below the
minimum value required for the specific control box.
It may be necessary to search experimentally for the best position by sliding (axial or rotation movement) the body that
contains the photoelectric cell in respect to the fastening clamp.
An inspection can be carried out by inserting a microammeter, with an adequate scale, in series to one of the two UV
photoelectric cell connection wires. It is obviously necessary to respect the polarity (+ e -).
For LGB control box the photocell coltage must be included between 200 microA and 500 microA.
Содержание COMIST 18
Страница 8: ...8 Metano Natural gas Gasolio Light oil CAMPO DI LAVORO WORKING FIELD N 0002920161 G P L L P G ...
Страница 25: ...25 GAS BURNERS CONTROLS LGB for small to medium capacity burners with or without a fan intermittent operation ...
Страница 26: ...26 GAS BURNERS CONTROLS LGB for small to medium capacity burners with or without a fan intermittent operation ...
Страница 28: ...28 GENERAL DIAGRAM FOR TWO STAGE L P G PRESSURE REDUCTION FOR BURNER OR BOILER N BT 8721 2GB Rev 21 03 90 ...
Страница 29: ...29 SCHEMA DISPOSIZIONE DISCO ELETTRODI DISK ELECTRODES RELATIVE POSITION DIAGRAM COMIST 18 N BT 9260 ...
Страница 34: ......