Tightness Control - Honeywell BCU 370 Technical Information

Function
BCU 370..I1..D3
L1
21
24
23
22
9 3 7
DG DL
min
DG
VG
BCU 370 · Edition 01.19
4 11 5 29 30
V1 DG V2
DG
VG..L
p /2
u
M
IC 20
DL
B VA
25
28
26
20
19
18
17
31 32 13
GIK

3 .3 Tightness control

On BCU 370..D3, the tightness con-
trol monitors the fail-safe function
of the gas solenoid valves if param-
eter 24 is set to 3.
The aim of the tightness control is
to identify an inadmissible leak on
one of the gas solenoid valves and
to prevent burner start. The other
gas solenoid valve continues work-
ing properly and takes over the safe
shut-off of the gas supply.
The test takes place during pre-
purge. The fan runs and the air
pressure opens the air/gas ratio
control GIK.
In the case of quick start (parameter
06 = 0), the test takes place after
burner operation during post-purge.
The pre- and post-purge times (pa-
rameters 18 and 19) must be set so
that their duration is at least as long
as the test period t .
P
▼
28