The Landis control box starts the fan and begins the pre-purging of the combustion chamber. The air pressure switch
controls the correct operation. At the end of the pre-purging phase, the ignition transformer cuts-in followed by the
opening of the gas valves. In case of missed ignition or accidental shutdown, the ionisation probe cuts-in and set the
burner in lockout mode within the safety time.
Gas pressure swi ch
Mo or
Air pressure swi ch
Transformer
Gas valve
High flame ON/OFF
Flame de ec ion
Lock ou
lamp
MANUAL RELEASE
SWITCH
"PAB" VERSION GAS BURNERS GAS TRAIN INSTALLATION AND SETTING INSTRUCTIONS
Fix the gas train to burner body by means of the 4 screws of the flange, pay attention to set correctly the gasket ( O-
ring ).
Connect electrically the gas train with the 6 pole plug.
Switch on the burner (it has already been tested in the factory, so it is pre set on average values) and verify the tightness
of gas train connections made during installation.
Act as follows to adapt the burner output to the boiler.
HIGH FLAME
1. Bring the burner in high flame , air inlet must be set at 75 ° (maximum opening position).
To adjust air capacity operate on the combustion head position.
Just in peculiar case it is necessary to reduce the air flow in high flame closing air intake damper.
2. The position of gas butterfly valve must be lower then 90° ( typically 85°. It is important not get over 90° to obtain
a perfect combustion during passage from high to low flame). Eventually adjust this position acting on the screw "1 ",
after loosening nut " 2 ".
3. Regulate gas capacity in high flame through the gas governor, or operate on the adjustable gas valve.
LOW FLAME
4. Choose the first stage position on the servocontrol ( normally between 10° - 30°) on the basis of the reduced charge
output required and switch the burner to low flame.
5. Regulate gas capacity, to obtain optimal combustion, changing the position of the gas valve disc, act on screw " 3 ",
CONTROL BOXES LANDIS & STAEFA LGB21/LGB22
2
3
1
LANDIS & STAEFA SQN 30 151A2700 AIR
DAMPER MOTOR
Remove cover to gain access to the adjusting cams.The cams are to be
adjusted through the suitable key provided for. Description:
I
- Limit switch for air damper "High Flame" position adjustment
(Max. power)
II - Limit switch for the air damper position at burner's shut down
III - Limit switch for air damper "Low Flame" position adjustment
(Min. power)
V - Limit switch for 2nd stage's solenoid valve opening release
NOTE : Cam V (to allow the 2nd stage's solenoid valve opening) must
be adjusted to an intermediate position between the Low and High
Flame ones (to an angle approximately 5° greater than the low flame
position).
420010243300 Blu 500.1 ÷ 1200.1 P AB Low Nox
4
Description
1
pressure swi ch con rol ime-ou
2
ime-ou for air pressure confirma ion
5
3
prewashing ime
4
safe y ime
6
5
preigni ion ime
6
ime-ou
pag.11
o enable fuel 2nd valve
B
9"
3"
30"
3"
3"
8"