In the last two posts, we considered the cooling of the exit temperature of a hot water tank with a given flow rate and heat input rate, and thought about recharge times once the hot water withdrawal was stopped. However, in real life you’d keep turning up the proportion of hot water as long as you could in order to keep your shower at a constant temperature. Of course, the cooler the water came out from the hot water tank, the more you’d need to use, making it cool down even faster.
