3.4 FUEL SUPPLY
The burners are teamed with one-piece pneumatic proportioning gas valves, via which the amount of gas
delivered, and hence the output produced, can be modulated.
A signal reporting pressure detected in the air circuit is carried to the pneumatic gas valve, which delivers an
amount of gas in proportion to the airflow produced by the fan.
The gas train, in order to render the dimensions efficent is assembled directly onto the burner body.
GAS TRAIN ASSEMBLY
Gas supply
Flange
D7376
Note: With the valve/manifold connection, accidental blocking of the intake can be compensated by
reducing the amount of gas delivered.
Gas valve
Valve model
Mixer model
Gas line connection
Working temperature
Max. working pressure
Min. working pressure
Max. inlet pressure
Valve class
Electrical supply
Protection level
3350
Gas pressure downline
test point (P2)
Gas pressure upline
test point (P1)
Gas valve
D7155
Honeywell VK4125V 10054
Honeywell 45.900.44-001
½" inlet
-15°C/70°C
30 mbar
15 mbar
60 mbar
B + B
220-240 V
IP 40 according to IEC 529
D7375
Air/gas mixer
Gas and combustive air are mixed in-
side the purging circuit (mixer), start-
ing from the intake inlet.
Through the gas train, fuel is intro-
duced into the intake air current and
optimal mixing commences with the
aid of a mixer.
7
GB
Air/gas mixer
in the suction circuit
Maximum gas flow
adjustment (V1)
Minimum gas flow adjustment
on the stabiliser (V2)
Gas compensation pipe
D7380