Non - domestic gas - fired forced convection air heaters for space heating not exceeding a net heat input of 300 kw , incorporating a fan to assist transportation of combustion air and or combustion products 借助风扇传输燃气和或燃烧产物的空间加热净加热输入功率不超过300kw的非家用燃气强制对流空气加热器
Fans consume more power than the pumps of a liquid system , but if the unit is installed in a facility that uses air distribution , only a slight power cost is chargeable against the solar space - heating system 风扇比起液体系统的泵，需要更多能量，但是如果工厂中建立的使用空气分配的单元，相对太阳能空间加热系统，仅仅需要很少的能量付出。
Liquid systems are suitable for a broader range of applications , such as hydronic space heating , service water heating , industrial process water heating , energizing absorption air conditioning , and pool heating , and as a heat source for series - coupled heat pumps 液体系统适用范围较宽，像液体循环空间加热、服务水加热、工业处理水加热、能量吸收空调、联合供热，和连续-联合热泵的热源。
If this system heats only water in the summer , the parasitic power consumption must be charged against the solar energy system because no space heating is involved and there are no comparable energy costs associated with conventional water heating 如果该系统在夏天仅仅加热水，因为没涉及空间加热且没有相应传统的水加热的等量能量消耗，在与太阳能系统相对的情况下（不使用太阳能，但与其比较） ，必须付出寄生能量消耗。
