Cause of error code E12

High limit stat open 

Solution for error code E12

Supply temperature too high. Caused by
- presence of air
- possible polluted impeller of the circulation boiler pump
- polluted internal ?lter

Check de-aerator. Replace when necessary the automatic de-aerator and restart boiler for de-aerating programm (17min.)

Check water ? ow over system. Clean when necessary the pump and or ?lter. Flush complete system

Check adjustment of balancing valves