Excess Conditions - Viessmann Vitoflex 300-UF Series Installation And Operating Instructions Manual

Operation

Excess Conditions

Excess temperature/power failure
CAUTION
DANGER OF THIS EQUIPMENT SUDDENLY GOING UP
IN FLAMES:
DO NOT open the doors or lids on the boiler plant!
- Switch on additional heat loads.
- The flue gas exhaust blower shuts down.
- The temperature-limiting safety switch triggers.
- The thermal safety flush valve opens at approx.
203°F (95°C). The excess heat is being dissipated
into the drain.
IMPORTANT
If the fixed high limit has triggered, it has to be manually
unlocked. The fixed high limit is situated at the top of the
boiler.
To reset, unscrew the black cap and press the button.
Note: Resetting is only possible when the temperature
has fallen to approx. 158°F (70°C).
Possible causes for excess temperature:
- Incorrect setting on the control module.
- Defective component of the system (pump or valve).
- Sudden drop in output to zero. The in-feed auger still
has to be emptied. The heat yet produced by this can
result in surplus temperature.
Activate "DISSIPATE SURPLUS HEAT" function!
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Vitoflex 300-UF Installation & Operating
Low water/excess water pressure
Possible causes:
Low water: Leakage in the heating system.
Excess water pressure: The expansion tank is not
functioning.
In either case, the boiler should be examined by a qualified
heating contractor.
Note: Unlock this malfunction with either the reset button
for the water level control system or for the
negative overpressure monitoring assembly, and by
pressing the OK button on the control panel.