... , underfloor system ,heat pump Or solar energy system .(heating power range from 3KW to 50KW) Boiler Series : Single heating boiler ... pump closed style(single heating system) Boiler heating power :3-20KW Hot water side Power is 30-200KW Safety and Heating boiler on ... element temp exceeds 110degrees, dry-heating protector start, disconnect the power supply ,then we should button “return”key by manual . ...