Viessmann Vitoflame 100 Service Instructions Manual page 7

Further details regarding the individual steps
Function test without gas supply
H Check the function sequence (see
program sequence on page 25).
H Switch ON the mains isolator
(outside the installation room).
H Start the burner; for this, switch ON
the system ON/OFF switch at the
control unit.
H With the soundness test set still
connected, gently build a pressure
of approx. 20 mbar (gas shut−off
valve closed).
The following program must now
run (see also program sequence on
page 25):
When there is a heat demand
(control indicator "Demand"
illuminates at the plug−in panel), the
air damper servomotor moves from
the "Closed" position to air damper
position stage 2 and returns to
stage 1 (ST 0 − ST 2 − ST 1).
Initial start−up, inspection and maintenance
The burner control unit program
sequence is started with the
following functions:
H The burner motor starts and the
combustion chamber is purged
(approx. 30 s).
H The electric ignition is started
(pre−ignition time approx. 2 s).
H The gas solenoid valve for stage 1
opens.
H The pressure inside the valves
drops.
H The gas pressure limiter switches
the burner OFF (not a fault
shutdown).
The burner control unit enters a
fault shutdown after the expiry of a
safety interval of 2 s, if the gas
pressure limiter does not shut
down the burner.
Remove the soundness test set and
close test port A.
(cont.)
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