TC · Edition 08.17 24
Function
3.1.4 Test instant TC 1, TC 2, TC 3
Two DIP switches are used to determine whether the
tightness of the gas solenoid valves is to be checked
before burner run, after burner run, or before and after
burner run.
3.1.5
Test instant for Mode 1: testing before burner run
Mode 1 = factory setting.
5s
10s
15s
Mode 1
Mains voltage L1 is switched on. In the case of untest-
ed valves, the LEDs
and
are yellow.
The tightness test starts with incoming thermostat/
start-up signal ϑ. If the valves are tight, the LEDs
and
are green. Once the safety interlock input sig-
nal
is active, the OK enable signal is forwarded to the
automatic burner control unit.
The tightness test is valid for up to 24 hours. If the safe-
ty interlock input signal
is not connected during this
time, the test is started again with the application of the
safety interlock input signal. Once the test has been
completed successfully, the OK enable signal is issued.
L1
(+)
ϑ
TEST
OK
Mode 1
t
1
10
6
12
t
L1
(+)
ϑ
TEST
OK
1
10
12
1
2
t
p
don’t-care
5
6
5
V1 leaking
V2 leaking
TEST
Leaks
If the tightness control TC detects a leak on one of the
two valves, the red LED lights up for a fault on valve V1
or valve V2
. A fault is signalled externally ,
e.g. by switching on a buzzer or a warning light.
L1
(+)
ϑ
TEST
OK
t
1
10
6
12
1
2
t
p
5
V2 leaking