Hot Water

Question

I don't understand your father's confusion about hot water. The boiler is set to around 140 degrees. When the water enters it is heated to this temperature, thus being "cooked". In his sefer p. 180 he says that this is a pesik resha de-lo nicha leh (in his teshuvah regarding solar heaters). If so, and if a pesik resha de-lo nicha leh is permitted, than it is permitted to use hot water on Shabbat. Those who forbid this say 1. It is pesik resha DE-NICHA leh or 2. Pesik resha de-lo nicha leh is forbidden. But if your father holds (in accordance with the Arukh and others) that pesik resha delo nicha leh is muttar, and if he holds that hearing the water falls into this category, logic would dictate that he holds that it is permitted to use hot water on Shabbat. The only solution I can think of is that your father only holds a pesik resha is permitted with de-rabbanan, but not de-oraita. But ifhe holds, like some, that it is permitted even de-oraita, then use of hot water should be permitted, right?