BIC · Edition 09.22
EN-8
WARnInG
– If reducing fittings or manual valves with internal
thread are installed, Δp
gas
on the integrated gas
measuring orifice is reduced.
➔
Reducing fitting with internal and external thread:
deviation from the flow rate curves may occur when
the cross-section of the reducing fitting differs from
that of the threaded gas connection
GA
or when
a manual valve is screwed directly into the burner.
➔
Reducing nipple with external thread at both ends:
no deviation from the flow rate curves occurs.
➔
Ensure an undisturbed flow to the measuring orifice!
➔
As not all the effects caused by the equipment are
known, setting the burner using the pressure values
is only approximate. It is possible to set the burner
precisely by measuring the flow rates or flue gas.
5.6 Restrictors
➔
The air volume required for the low-fire rate at a
given air pressure is determined by the ignition
position of a butterfly valve, a bypass hole in the air
valve or an external bypass with restrictor.
➔
Burners as from construction stage E (see type
label) are equipped with gas flow adjustment to
replace the restrictor in the gas pipe.
5.7 Hot air compensation
➔
The combustion air pressure
p
air
must be increased
in hot air operating mode (lambda = constant).
0
50 100 150 200 250 300 350 400 450 500 550 600
100
150
200
300
250
Air temperature [°C]
Air pr
essur
e p
air
[%]
➔
The gas pressure is increased by 5–10 mbar.
➔
The total burner capacity
P
gas
rises as the air tem-
perature increases.
0
50 100 150 200 250 300 350 400 450 500 550 600
100
110
120
Air temerature [°C]
Total capacity P
tot
[%]
5.8 Burners with electrodes with air connection
➔
Burner head marking (..D) or (..E)
purge air tube
purge air nozzle
d=4.5mm
Rp 1/4
10
20
30
40
1
2
3
p [mbar]
0
10
20
30
40
0
1
2
3
Pressures for purges electrodes
Q purging air [m
3
/h]
➔
A purge air volume of approx. 1.5 to 2 m³/h per
electrode is recommended.
➔
The purge air may not be switched off until the
furnace is cold and formation of condensation is
no longer possible.
5.9 setting the air pressure for low fire and
high fire
1
Shut off the gas and air supply.
BIC
➔
Air measuring nipple
L
, outside dia. = 9 mm (0.35").
2
L
➔
Loosen the screw 2 turns.
3
L
4
Fully open the air supply.
5
p
atm.
p
air
0
➔
p
atm.
= atmospheric pressure.
BICA
➔
Air measuring nipple
L
, outside dia. = 9 mm (0.35").
