確實，發動機冷卻係隻在做小循環，包括HeatorCOre，大循環沒有全部介入，而且一直錯誤的認為

Thermostat should be located close to Upper hose (as many diagram showing), which is not the case in Honda, it(Thermo Housing) is located on  Lower (return）line by engine block,  not upper line.