Combustion Check; Ionization Current - Roca CRONO 4-G COMPACT Instrucciones De Instalación, Montaje Y Funcionamiento Para El Instalador

4.4 ELECTRODE PROBE POSITIONING
Make sure that the ceramic
is behind the diffuser disc
and level with it.
Probe
D4575

4.5 COMBUSTION CHECK

It is advisable to set the burner according to the type of gas used and following the indications of the table:
EN 676
Theoretical max. CO
GAS
0 % O
G 20 11.7
G 25 11.5
G 30 14.0
G 31 13.7

IONIZATION CURRENT

The minimum current necessary for the con-
trol box operation is 5 µA.
The burner normally supplies a higher cur-
rent value, so that no check is needed.
To measure the ionization current, open the
connector CN1 (see electrical scheme page 8)
and insert your microammeter.
4.6 AIR PRESSURE TEST POINT
ATTENTION
Should the air pressure test point device
(A) come loose by accident, you are
advised to turn it to the correct position as
illustrated in figure 10.
Connect air pressure test point (A) to
the pressure switch (C) inlet (-).
Connect air pressure test point (B) to
the pressure switch (C) inlet (+).
NOTE
There is a gauged diaphragm inside the
pipes, located near the air pressure test
points. If pipes are replaced, reuse the
above-mentioned diaphragms.
3217
Ionization
probe
Setting CO
2
λ = 1.2
2
9.7
9.5
11.6
11.4
Diffuser Ignition electrode
1,7
WARNING 2,5 ÷ 3,5 mm
AIR EXCESS:
max. output λ ð 1.2 – min. output λ ð 1.3
%
2
λ = 1.3
9.0
8.8
10.7
10.5
Fig. 9
Terminal block
of control-box
1
D4244
A
10 GB
Electrode
CO
mg/kWh
mg/kWh
ð 100
ð 100
ð 100
ð 100
Connector
D5006
Fig. 10
NO
x
ð 170
ð 170
ð 230
ð 230
Probe
B
C