14
420010250900
BLU 500.1 ÷ 1200.1 PR SW
EN
ADJUSTMENT OF GAS MINIMUM PRESSURE SWITCH
Unscrew off and remove cover M. - Set regulator N to a value equal to 60% of gas
nominal feed pressure (i.e. for nat. gas nom. pressure = 20 mbar, set regulator to a
value of 12 mbar; for L.P.G. nom. pressure of G30/G31- 30/37 mbar, set regulator
to a value of 18 mbar).Screw up cover M.
ADJUSTMENT OF THE AIR PRESSURE SWITCH
Unscrew screws A and B and remove cover C.- Set the pressure switch to the mini-
mum by turning regulator D to position 1.
- Start the burner and keep in low flame running, while checking that combustion is
correct. Through a small cardboard, progressively obstruct the air intake until to
obtain a CO2 increase of 0,5÷0,8% or else, if a pressure gauge is available, con-
nected to pressure port E, until reaching a pressure drop of 1 mbar (10 mm of
W.G.). - Slowly increase the adjustment value of the air pressure switch until to
have the burner lockout. Remove the obstruction from the air intake, screw on the
cover C and start the burner by pressing the control box rearm button.
Note: The pressure measured at pressure port E must be within the limits of the pressure switch working
range. If not, loose the locking nut of screw F and gradually turn the same: clockwise to reduce the pres-
sure; counterclockwise to increase. At the end tighten the locking nut.
2,5
5
10
15
50
2
5
35
3
0
40
45
20
0,4
0,6
0,9
3,0
1,5
2,
1
1
,8
2,4
2,7
1,2
I
L
M
N
A
B
C
D
E
F
G
H
IONIZATION CURRENT
LANDIS & STAEFA
1
LGB21-LGB22 min. 3
µ
A
LMG21-LMG22 min. 2
µ
A
With the burner switched off, connect a DC microammeter with a 0÷50 or 0÷100 µA dial. When the burner is run-
ning, and is properly adjusted, the value read must be steady and never be smaller than 3 µA.
In order to change the burner operation from natural gas to LPG you have to follow these instructions :
- Remove the blast tube. - Remove the ignition electrode. - Replace 4 Diffusers (only 700.1, 1000.1, 1200.1) with
LPG version, remove A screws.
-
Replace Tooth with LPG version, remove B screw.
-
Install the ignition electrode
correctly. - Install the blast tube .
CHANGE BURNER OPERATION FROM NATURAL GAS TO LPG
A
B
