Valves with female screw ends for water - heating system 水暖用內(nèi)螺紋連接閥門
In some situations , solar water - heating systems could be more expensive than conventional water heaters , particularly if electrical energy costs are high 在一些情況下,太陽(yáng)能水-加熱系統(tǒng)可能比傳統(tǒng)的水加熱器更昂貴,特別是如果電能消耗很高的情況。