# How to prevent explosive boiling? **URL:** \ **Category:** Factual Questions\ **Created:** [July 13, 2020, 1:12pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212 "2020-07-13T13:12:51Z")\ **Posts on this page:** 15\ **Page:** 2
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [July 14, 2020, 3:17pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/21 "2020-07-14T15:17:24Z")
I’m surprised that it’s possible to get superheating in a pot heated from the bottom. I’d expect that convection alone would be enough to nucleate the boiling. ---
**Author:** ![echoreply](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/echoreply/32/3641_2.png) [@echoreply](https://boards.straightdope.com/u/echoreply)\ **Post date:** [July 14, 2020, 7:20pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/22 "2020-07-14T19:20:09Z")
I’m surprised the salt doesn’t provide nucleation points. Maybe when it dissolves it’s too small. [You can also add all of the pasta to the cold water](https://altonbrown.com/cold-water-method-pasta-recipe/). I’ve done it this way before, and I can’t tell the difference between pasta cooked this way and the traditional way. ---
**Author:** ![jjakucyk](https://avatars.discourse-cdn.com/v4/letter/j/3d9bf3/32.png) [@jjakucyk](https://boards.straightdope.com/u/jjakucyk)\ **Post date:** [July 14, 2020, 8:49pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/23 "2020-07-14T20:49:39Z")
> [@echoreply](#): > > I’m surprised the salt doesn’t provide nucleation points. That’s a good point. You DO salt your pasta water, don’t you @Machine_Elf? ---
**Author:** ![TroutMan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/troutman/32/6721_2.png) [@TroutMan](https://boards.straightdope.com/u/TroutMan)\ **Post date:** [July 14, 2020, 11:05pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/24 "2020-07-14T23:05:58Z")
Dissolved salt doesn’t provide nucleation sites. When salt dissolves, it isn’t just smaller salt molecules in water, it’s the ions, and those don’t have a surface on which bubbles can form. If you throw some salt in water at 100 C, it will briefly provide sites until it dissolves, but you’re likely to get a sudden vigorous boil by doing that. Throwing it in earlier won’t help because it will be dissolved before the water reaches the boiling point. ---
**Author:** ![Fiendish\_Astronaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fiendish_astronaut/32/3295_2.png) [@Fiendish\_Astronaut](https://boards.straightdope.com/u/Fiendish_Astronaut)\ **Post date:** [July 14, 2020, 11:13pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/25 "2020-07-14T23:13:31Z")
> [@puzzlegal](#): > > I have no particular concerns about my water supply, but I always fill the pasta pot with cold water because I don’t trust what might be leaching off the inside of the hot water heater, or collecting there. I always fill my pan with hot tap water as I think it uses much less energy overall. I figure that I’m boiling the water so I’m purifying it and it doesn’t matter if there are impurities to start with. Am I wrong? ---
**Author:** ![TroutMan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/troutman/32/6721_2.png) [@TroutMan](https://boards.straightdope.com/u/TroutMan)\ **Post date:** [July 14, 2020, 11:20pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/26 "2020-07-14T23:20:20Z")
> [@Fiendish\_Astronaut](#): > > I figure that I’m boiling the water so I’m purifying it and it doesn’t matter if there are impurities to start with. Am I wrong? Boiling won’t do anything about heavy metals that might leach from your water heater or pipes into the water. It’s generally not recommended to use hot water for drinking or food preparation. ---
**Author:** ![Fiendish\_Astronaut](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fiendish_astronaut/32/3295_2.png) [@Fiendish\_Astronaut](https://boards.straightdope.com/u/Fiendish_Astronaut)\ **Post date:** [July 14, 2020, 11:24pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/27 "2020-07-14T23:24:24Z")
Argh I’ve been slowly poisoning myself for years! ---
**Author:** ![puzzlegal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/puzzlegal/32/3827_2.png) [@puzzlegal](https://boards.straightdope.com/u/puzzlegal)\ **Post date:** [July 14, 2020, 11:29pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/28 "2020-07-14T23:29:16Z")
Right. I’m not worried about bacteria, I’m worried about heavy metals and other crud. But I imagine is is more cost-effective to start with hot water. I bet my water heater is more efficient than my stove. ---
**Author:** ![filmore](https://avatars.discourse-cdn.com/v4/letter/f/7993a0/32.png) [@filmore](https://boards.straightdope.com/u/filmore)\ **Post date:** [July 15, 2020, 2:09am UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/29 "2020-07-15T02:09:45Z")
Maybe throw in a few grains of rice, some potato flakes, or something else starchy. Stuff like that will practically dissolve away or not be noticed in the final result. ---
**Author:** ![dougrb](https://avatars.discourse-cdn.com/v4/letter/d/76d3ee/32.png) [@dougrb](https://boards.straightdope.com/u/dougrb)\ **Post date:** [July 15, 2020, 7:10pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/30 "2020-07-15T19:10:31Z")
> [@puzzlegal](#): > > I bet my water heater is more efficient than my stove. I bet your microwave is more efficient than either. ---
**Author:** ![PoppaSan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/poppasan/32/189_2.png) [@PoppaSan](https://boards.straightdope.com/u/PoppaSan)\ **Post date:** [July 15, 2020, 11:13pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/31 "2020-07-15T23:13:32Z")
The last several water heaters I’ve had were glass lined so it’s not the tank I’d worry about. ---
**Author:** ![filmore](https://avatars.discourse-cdn.com/v4/letter/f/7993a0/32.png) [@filmore](https://boards.straightdope.com/u/filmore)\ **Post date:** [July 15, 2020, 11:23pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/32 "2020-07-15T23:23:19Z")
> [@Fiendish\_Astronaut](#): > > I always fill my pan with hot tap water as I think it uses much less energy overall. I’ve wondered about the energy difference of that as well. One issue is the heat loss from the distance between the water heater and the faucet. It would be easier to decide if you filled the pot straight from the water heater, but there is going to be some energy loss as the water goes through the pipes and the wasted hot water left behind in the pipes when you turn the faucet off. ---
**Author:** ![Snipe70e](https://avatars.discourse-cdn.com/v4/letter/s/51bf81/32.png) [@Snipe70e](https://boards.straightdope.com/u/Snipe70e)\ **Post date:** [July 16, 2020, 4:07am UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/33 "2020-07-16T04:07:34Z")
Depends on the city or water company that is supplying the water. I do not know what is in the water that is in San Jose California, but I do know it will eat up a brass valve. In high rise buildings to preform annual maintenance on some system the waster has to be shut off. I have replaced the valve on the system one year and 12 months later the vvalve will not hold and I have to replace it again. Don’t know what is in the water but it is eating brass. I do not drink tap water. It is either bottled or from a RO system. Thhat is one reason not to use tap water in cooking. ---
**Author:** ![am77494](https://avatars.discourse-cdn.com/v4/letter/a/d2c977/32.png) [@am77494](https://boards.straightdope.com/u/am77494)\ **Post date:** [July 16, 2020, 12:35pm UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/34 "2020-07-16T12:35:50Z")
> [@Snipe70e](#): > > I do not know what is in the water that is in San Jose California, but I do know it will eat up a brass valve. In high rise buildings to preform annual maintenance on some system the waster has to be shut off. I have replaced the valve on the system one year and 12 months later the vvalve will not hold and I have to replace it again. I do have some expertise on valves and am not sure I understand the problem. Is this a gate valve or a ball valve ? Is the water leaking out through the body or is the valve not being able to isolate ? The internals of brass valves are not made of brass : for example the ball in a ball valve is steel. ---
**Author:** ![Snipe70e](https://avatars.discourse-cdn.com/v4/letter/s/51bf81/32.png) [@Snipe70e](https://boards.straightdope.com/u/Snipe70e)\ **Post date:** [July 19, 2020, 4:53am UTC](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212/35 "2020-07-19T04:53:36Z")
Ball, gate, globe valves. I mean when you shut the valve off water will still flow through the valve. That makes it impossible to isolate a system. Your are right the ball in a ball valve is normally steel. But the seats can be brass. And the disk in gate valves are mostly brass or have brass seats. Globe vlaves brass or steel. The valve will no longer seat and leaks through. [Previous page](https://boards.straightdope.com/t/how-to-prevent-explosive-boiling/915212.md?page=1)