Group 1 - The article discusses the energy-saving strategies for air conditioning usage when leaving home for a short period, specifically comparing fixed-frequency and variable-frequency air conditioners [3][7]. - Fixed-frequency air conditioners consume a constant amount of energy, and it is more economical to turn them off when leaving for a few hours [3][5]. - Variable-frequency air conditioners are more efficient when left on for short periods, as they consume less energy during operation compared to the energy required to restart [3][7]. Group 2 - The lifespan of air conditioners is primarily determined by the compressor, and minimizing the frequency of on-off cycles can extend the life of fixed-frequency models [7]. - Variable-frequency air conditioners operate at lower power levels, which can help prolong their lifespan if not frequently turned off and on [7]. - Safety concerns are raised regarding leaving air conditioners running while away from home, particularly if the unit is old or improperly installed, which could lead to fire hazards [8][9].

正值盛夏，随着气温的升高，空调成了人们的生活必需品，但很多人对空调的使用存在误区，要么过度 依赖导致健康问题，要么因担心耗电而强忍高温。如何正确使用空调，兼顾健康和节能？ 《 人民日报 》（ 2025年07月21日 12 版） (责编：袁勃、赵欣悦) 日常生活中，一些老年人因担心受凉或耗电而拒绝开空调，其实过度闷热对健康的危害更大——高温会 导致心率加快、血压升高，增加心脑血管疾病风险，甚至诱发中暑。张卫茹为老年人提供了一些使用空 调的建议。一是破除认知误区：高温对老年人的风险远高于适当使用空调，夏季因热射病去世的人群 中，老年人占比超过60%，不必因担心"受凉"而硬扛；二是渐进式适应：初次开空调时可将温度设为28 摄氏度，让身体慢慢适应，后续再根据舒适度微调，避免一开始就用过低温度；三是掌握分段使用法： 每天分时段开空调（如上午10点至下午4点高温时段开启），其他时间开窗通风，既保证凉爽又减少依 赖；四是结合其他降温方式：开空调时可搭配风扇（摇头模式），让冷空气循环更均匀，既能降低空调 负荷，又能避免局部过冷；五是请子女多关注，帮助老人设置好空调温度和定时功能，讲解过度闷热的 健康风险，同时定期帮老人清洁空 ...