Slant/Fin VHG-100-CH, Installation And Service Manual

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96
E93.1901EN032 Installation and Service Manual SlantFin VGH-CH / CO
A
PPLIANCE SELECTION
The control is designed to store specific parameter sets of different boiler models.
By defining specific setting for different appliance models the same control can be used for a complete product
range. Depending on which model the control is applied to, it will only be necessary to change a single parameter.
When this parameter (138) is changed, the following settings are changed:
• Maximal fan speed
• Minimal fan speed
• Ignition speed*
• Maximum flue gas temperature
*Ignition speed is the same as Pre-Purge Speed and Post Purge speed.
The following appliances are available:
APPLIANCE SELECTION (Parameter 138)
Boiler type:
80 CH 100 CH 120 CH 150 CH 180 CH 90 CO 150 CO 200 CO
Natural gas 50 52 54 50 52 50 50 50
Propane 51 53 55 51 53 51 51 51
Not Used x 54 - 55 52-55 52-55 52-55
Attention !
This does not apply to the external igniter BCU, see mounting instructions of that BCU.
Ignition cycle
During the ignition cycle multiple safety checks are active
False flame detection If flame is detected at the end of the pre-spark period ( Pre-ignite ) a lockout error
occurs.
Re-ignition If at the end of the safety period, no flame is detected, the control will go to post-purge
in order to remove the unburned gas. After this a re-ignition attempt is started
following the same cycle.
The number of re-ignition attempts is limited to
Max_Ignit_Trials after which a lockout
occurs.
Flame establishing
time
Sparking stops in the Flame Proving state to allow for ionization detection.
The Flame Proving state takes Safety_Period - Ignit_Period .
Flame out too late If at the end of the Post purge 0 state, the flame is still detected a lockout follows.
Flame loss When a flame is lost during a burn cycle the control will restart the boiler once. At the
second flame loss the boiler will stop and blocking mode follows. The number of
restarts is limited by the
Max_Flame_Trials setting. (Default set to 1)
Fan supervision
The fan speed is continuously monitored.
F
LAME DETECTION
When the boiler is firing, and the flame is not detected anymore, the gas valve will be closed, and the control will
perform a post-purge, after which a restart will take place.
The presence of a flame is measured through the flame rod that points into the flame. The flame current is measured
by the control as ionization in micro amps (
μA
).
When the flame current is above Flamerod_Setpoint plus Flamerod_Hysterese (1.0
μ
A plus 0.5
μ
A) a flame will be
present. When the flame current is below Flamerod_Setpoint (1.0
μ
A) the flame will not be present.
Table 11.6
Figure 11.5
Table 11.7