①打開(kāi)熱介質(zhì)旁路閥 ②關(guān)閉熱介質(zhì)入口閥 ③關(guān)閉熱介質(zhì)出口閥 ④打開(kāi)冷介質(zhì)旁路閥 ⑤關(guān)閉冷介質(zhì)入口閥 ⑥關(guān)閉冷介質(zhì)出口閥