Operating instructions
30
5
5.4.2 Continued program sequence
The continued sequence can be found in the sequence
diagram on the right.
Display
Sequence diagram
Flame signal
Ignition
V1 / V2
Heat demand
Flame stabilisation period
Safety period
Ignition
speed
Modulating
operation
Post purge
speed
The unit carries out 5 ignition attempts.
After the fifth unsuccessful attempt the display shows the
code F21. Initiate a restart by pressing the reset button.
5.5 Commissioning
Notes on initial heating up of the system
•The commissioning and purging of the system should
be carried out immediately after the system has been
filled.
•When first heating up the system, ensure that the
maximum possible water flow through the condensing
unit is guaranteed. To do this all radiator valves should
be fully opened.
•The heat up should be carried out with low supply
temperatures and at low load.
• On multi-boiler systems all units should be
commissioned at the same time at low load.
❑ Open gas isolating valve
❑ The electrical wiring must have been tested.
❑ Water pressure is available, cocks are open,
sufficient heat demand is ensured.
The WTC has been factory preset.
Due to its fully automatic compound regulation an
adaptation to various gases from one gas family is not
required.
Therefore the values set during first commissioning have
to be checked only once. The values set can be found in
the technical data.
The following checks should be carried out:
•measuring the O
2
content at nominal load and partial
load (conversion table O
2
– CO
2
see appendix).
Adapting nominal load
• Using parameter P37 the heat rating can be reduced
in percentage values (see Ch. 6.3.3).
•Using parameter A10 the maximum fan speed can be
increased (see Ch. 6.4.1).
A PC with Software WCM Diagnostic is required to
be able to set parameter A10 (see Ch. 6.4.1).
Once a correction has been made re-check nominal and
minimum load.
Note: The rating set may deviate from the burner
rating given on the name plate by a
maximum ± 5%.
O
2
setpoint: Natural Gas LPG
O
2
= 5.3% O
2
= 5.1%
The rating is set as detailed in Ch. 5.5.2.
If the value deviates by more than ± 0.6%, a
correction is required.
•Ratings measurement at nominal load (see Ch. 5.6).