Unigas HRX2050R, Service Manual

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33
10.5 FGR mode choice
1st level 2nd level 3rd level 4th level 5th level 6th level Description
Param & Display
Flue Gas
Recirc
FGR-Mode AUX3onCurve
time
temperature
temp. contr.
TCautoDeact
deactMinpos
auto deact According to the preference and
instruction in the table below.
Description of the FGR mode.
FGR-Mode Description
LMV50
LMV51.3
LMV52.2
LMV52.4..
.
Aux3onCurve
Flue gas recirculation (FGR) function is deactivated.
Auxiliary actuator 3 is driven along its parameterized ratio control curve
● ●
deactivated
After the ignition position, auxiliary actuator 3 is always held at the minimum position for flue gas
recirculation (indicated with #) and the flue gas recirculation temperature is not evaluated (display
XXX).
This ensures that the system is operated in a safe state if the flue gas recirculation setting could
not be fully realized.
We recommend performing burner start-up using this setting prior to setting the flue gas
recirculation curve
●
time
Auxiliary actuator 3 maintains the ignition position until an adjustable time is reached (parameter
“DelaytimeFGR….”).
During the operation, the burner regulate its load as per the set curve points, without flue gas
recirculation.
● ●
temperature
Auxiliary actuator 3 maintains the ignition position until an adjustable temperature is reached
(parameter “FRG On Temp …”).
During the operation, the burner regulate its load as per the set curve points, without flue gas
recirculation.
● ●
temp.contr.
The position of auxiliary actuator 3 is determined depending on the flue gas temperature and the
ratio control curve.
In addition, the actuator can maintain the ignition position until an adjustable time (parameter FGR
On Time …) is reached
●
TCautoDeact
Same manner of operation as temp.contr., but the function is automatically deactivated should the
flue gas sensor become faulty.
The actuator is driven to the minimum flue gas recirculation (FGR) position and a warning is issued
●
deactMinpos
After the ignition position, auxiliary actuator 3 always maintains the minimum flue gas recirculation
(FGR) position (indicated by #) and the flue gas recirculation (FGR) temperature is not evaluated
(display of XXX).
The system can thus be driven to a secure state, if it was not possible to fully complete the flue gas
recirculation (FGR) settings.
It is recommended to use this setting for commissioning the burner before adjusting the flue gas
recirculation (FGR) curve
auto deact
Flue gas recirculation (FGR) with temperature compensation was automatically deactivated. Same
operation mode as deactMinpos, but a warning is issued
●