Instruction manual

41
Instructions for the installer
3.25 - BURNER PRESSURE ADJUSTMENT
PK230X 2S - PK300X 2S - PK348X 2S
WARNING!
All the instructions indicated below are for the
exclusive use of qualified UNICAL service te-
chnicians.
All the boilers are supplied already calibrated
and tested. However, if it is necessary to change
the calibration, the gas valve must be re-calibra-
ted.
Warning: during this operation do not request any DHW draw-
off .
A) Max output adjustment
- Remove the sampling point cap and insert a suitable C02
gas analyserin the flue outlet terminal.
MAXIMUM OUTPUT ADJU-
STMENT SCREW
- Via the e-bus controller activate the "Test" mode and run
the boiler at maximum output (refer to procedure indicated
on page xx).
- Check that the percentage of C02 is within the values
indicated in the table "Burner pressures"
- If necessary correct the value by turning the adjustment
screw "A" in a CLOCKWISE direction to increase the value
and in an ANTICLOCKWISE direction in order to decrea-
se it.
Flue sam-
pling point
Levels
CO2 (%)
min
Levels
CO2 (%)
max
Fan
speed %
Consump.
min.
Gas nat. (G20)
min max
Diafraghm
collettore
(Ø e n. fori )
PKX 150
Starting
Power
%
FL FH
20 3,7 m³/h 14,8 m³/h- 9,1 9631 9,09,1 60
In case of gas valve replacement or difficult
ignition:
Tighten the maximum adjustment screw "A"
in a clockwise direction until you arrive to
the abutting end, than slacken for 7 turns.
Verify boiler ignition; if the boiler goes into
lockout slacken the screw "A" again of one
turn, than retry to light the boiler. If the boiler
goes into lockout again, carry out the above
indicated operations until the boiler fires.
At this point carry out the burner adjustment
as previously indicated.
Check the C02 levels often, especially at low output
INJECTORS - PRESSURES
Gas
Type
Supply
Pressure
(mbar)
Ø
Injectors
(mm)
Consump.
max.