Gas Pressure Switch - Safety Checks - Maintenance - Uv Cell - baltur COMIST 180 Manual De Instrucciones

GAS PRESSURE SWITCHES
Gas pressure control pressure switches (minimum and maximum pressure) have ther task of preventing the burner
operating when gas pressure is not within planned range.
It is clear that the minimum pressure control switch must make use of the contact that is closed when the switch detects
pressure higher than its own setting.
The maximum pressure switch must make use of the contact which is closed when the switch detects pressure lower
than its own setting.
Minimum and maximum gas pressure switches must be set when the burner is tested.
Setting depends on pressure detected from time to time.
The pressure switches are connected in series, therefore operation (i,e, opening of the circuit) of the switches does not
consent switch-on of the equipment.
Remember that if any of the pressure switches operates (i.e. the circuit is opened) while burner is operating (flame lit),
the burner stops immediately.
When the burner is tested, correct pressure switch operation must be checked.
By using the adjustment devices, it can be verified whether the pressure switch that stops the burner actually operates
(i.e. opens the circuit).
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 micro-ammeter, 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 -).
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