hot water

Answer

Answered by Chaim Yisrael Abadi

First of all, a hot water heater never keeps an exact degree. It goes on and off. 112 degrees would basically be an average. You need to know that it does not go higher than 125 degrees, at any time. Many can fluctuate up to 15 degrees in either direction (big buildings). Home hot water heaters can be a 10 degree differential. If it stays below 125 degrees, then you can use hot water for any use except showering. For separate Halachic reasons relevant only to showers and baths, the degrees in a shower or bath has to be 10 degrees lower than 125 (or 115 degrees). So you should make sure to add some cold water to a shower or bath as you would probably normally do anyhow. THEN many homes and buildings have systems that the hot water to your sinks, showers, etc. are coming from mixing valves that are fed by water that is heated to a much higher degree, then are run through the mixing valve which has cold water mixing with the hot water. So even if you test the water at your sink, it is not any proof 100% that the water never gets heated to 125 degrees. Then even though the new water getting cooked is a psik reisha d'lo nicha ley, by a d'oraissa of Bishul in yad soledes bo we follow the shitos that assir. In this case, you cannot use the hot water at all. I hope this clears up this confusing issue. If I wrote anything to the contrary, this overrides it. Thanx, CYA