elco VECTRON G 03.200 DUO Betriebsanleitung Seite 24

Function
Operating function
Safety function
Function description
Control thermostat indicates heat
–
requirement.
The operating program of the control
–
system starts up if the air pressure
switch contact is in its idle position,
and is receiving a signal from the gas
pressure switch, indicating that there
is sufficient pressure.
Burner motor running
–
Pre-ventilation time 24 s.
–
During the pre-ventilation period:
fan pressure is monitored
–
the furnace is monitored for flame
–
signals.
After the pre-ventilation period has
expired:
the ignition system is activated
–
the main valve and safety valve are
–
opened
burner start-up
–
Compact valve assembly
F4 Low gas-level protection
F6 Low air-level protection
Y13 Solenoid valve stage 1
Y14 Solenoid valve stage 2
Y15 Safety valve
1 Thermally triggered (safety shutoff
valve (installed onsite)
104 Gas pressure controller
106 Filter
108 Gas ball valve (installed onsite)
119 Measuring point for gas pressure
119.1Measuring point for air pressure
24
Monitoring
The flame is monitored by an ionisation
probe. The insulated probe is fitted to
the gas head and leads through the
turbulator to the flame zone. Note that
the probe MUST NOT be allowed to
come into electrical contact with
earthed (grounded) components.
If a short circuit occurs between the
probe and the burner, the burner
switches to malfunction mode.
When the burner is in operation, there
is an ionised zone within the gas flame,
which allows a rectified current to flow
from the probe to the burner.
The ionisation current must not drop
below 8 µA.
03/2005 - Art. Nr. 13 018 069A
Safety functions
If no flame appears when the burner
–
starts up (release of gas), a safety
period of up to three seconds elapses
before the burner shuts down and the
gas valve closes.
If the flame goes out during
–
operation, the gas supply cuts out
within one second and the control
unit triggers an emergency shutdown.
If there is insufficient air during the
–
pre-ventilation phase, the burner will
not start, and an emergency
shutdown takes place.
An emergency shutdown likewise
–
takes place if there is insufficient air
during operation.
The burner will not start if the gas
–
supply is insufficient. If the gas
supply drops during operation, the
gas valve closes and the burner
shuts down. This does not result in
an emergency shutdown. The burner
restarts automatically when gas
pressure returns to its correct level.
Note
Fire regulations normally stipulate that
gas-fired devices must be fitted with a
thermally-triggered shutoff valve.