Burner Control Unit Lgm 29.Xx - Viessmann VITODENS 200 Start-Up And Service Instructions

Burner Control Unit LGM 29.XX

Program sequence
Call for heat
Ionization
Safety chain (FHL)
Gas combi valve
Ignition transformer
Combustion air modulation
Time in sec.
signal required
signal invalid
signal required for transition to next phase
Standby
Waiting time until next call for heat
start. Differential air pressure sensor
must be reset and the speed feedback
signal (HALL) must record that fan is
stationary.
Start-up and initial boiler run time
Start takes place when a call for heat
is received from the temperature
controller, provided no air pressure is
detected. The fan motor receives
voltage. The speed signal (HALL) and
the differential air pressure voltage
signal must be received by the burner
control unit LGM 29.XX within approx.
70 seconds, otherwise a fault message
is transmitted. During the initial boiler
run time, self-tests take place within
the burner control unit LGM 29.XX.
Pre-purge time
The combustion chamber is flushed out
by the fan.
Pre-ignition time
Ignition spark is initiated.
Safety time
The gas combination valve coils receive
voltage (energized), flame monitoring is
activated. Ignition is switched off after
approx. 4 seconds.
If the flame is not recognized during
ignition after three trials, automatic
lockout takes place.
< 71 2 0.2 < 5
Burner operation (green LED is lit)
Burner operation begins after the safety
time has elapsed, and flame recognition
has taken place successfully. The
burner control unit modulates from its
ignition load according to the currently
selected setpoint value.
After controlled shutdown (heat
demand is satisfied), auto reset to the
standby mode takes place.
Shutdown
The gas valve is de-energized.
Internal tests are performed.
Test time
Auto reset is the end of the shutdown
phase after controlled switch-off.
Auto reset also takes place after
resetting, failure of the flame during
operation or after a call for heat is
terminated before the start of the safety
time.
Safety chain (FHL)
The fixed high limits must be closed at
all times during the entire period of
operation, otherwise automatic lockout
takes place immediately.
Modulation range
5 Heating mode
Additional Information
max. 51
Burner control unit LGM 29.XX
The burner control unit LGM 29.XX
performs self-tests in the following
instances:
H when the burner has been in
continuous operation for more than
24 hours,
H before each time the burner is
switched on,
H after each time the burner is
switched off.
Behavior in the event of malfunctions
If faults are detected, either no start-up
takes place or automatic lockout is
triggered. In case of all safety-
relevant malfunctions, the gas supply is
cut off. Automatic lockout takes place
H when flame establishment fails
before the end of the flame
recognition time,
H in the event of an uninterrupted delay
of the flame signal for more than 3
seconds,
H in the event of an incorrect differential
air pressure sensor signal longer than
70 seconds,
H in the event of internal faults.
In the event of a line voltage drop, the
burner control unit either operates
without a fault indication function or
goes into reset position (gas valve
closed).
When the line voltage reaches its
normal level again, burner control is
ready for another start-up.
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