Hot water dissolves lead more quickly than cold water and is therefore more likely to contain greater amounts of lead. Never use water from the hot water tap for drinking, cooking, or making baby formula.
Hot water dissolves lead more quickly than cold water and is therefore more likely to contain greater amounts of lead. Never use water from the hot water tap for drinking, cooking, or making baby formula.
Wouldn’t all the dishes and utensils be exposed to lead when you use the dishwasher then? Or is it negligible as long as it’s not directly ingested?
I think it’s negligible compared to ingesting. I think most dishwashers do a final cold rinse, yeah? I could be wrong on that though.
I’ve never seen a dishwasher with 2 supply lines, they usually only hooked to hot.
Or cold with an internal heater, but still a single supply line.
We need that dishwasher guy to look into all of this.
He did already and that’s why we know most dishwashers (in the US) are fed by one line coming from the hot water tap.
I mean about the hot water having lead and other heavy metals part.
The steam that comes out of dishwashers I’ve used after washing would seem to indicate otherwise. Wouldn’t that temperature shock be dangerous to the ceramics?
Did a bit of research and there is a lot of disagreement on whether dishwashers should be connected to hot or cold supply lines. Might depend on the model somewhat.
It mostly depends on where you are in the world and what the wiring is designed for. 220V heating elements are abundantly powerful enough to heat water of any temperature to a useful temperature within the early stages of a wash cycle, and dishwashers with such heating elements are usually designed for cold water, for consistency, because the water in the pipes is always room temperature at first anyway. In places where the dishwasher is built for, and will be connected to 110V electrical supply, they will need the water to be pre-heated (including running the hot tap at the sink where they are plumbed from). If you read the manual, it almost certainly says so.
No matter what voltage they are designed for, they are almost exactly the same in all other respects. You might assume your dishwasher is smart enough to know what temperature the water is and that its magic electronics can run the water long enough or run the heater long enough or do something to make sure it gets to the specified temperature at some point before the cycle is considered done, however in basically all cases it does not, despite all the marketing bullshit trying to tell you how smart they are, they are actually very simple machines and they operate on nothing but very simple, factory-designed timers and cycles in all but the most esoteric designs. They are not smart enough to properly heat the water and almost none of them even have any sensor to detect the temperature or control the heating element in any useful way besides hopefully making sure it doesn’t burn your house down. They work because the combination of the heating element and the water supply together are enough to eventually make the water hot enough to wash properly. On 220V it’s easier to specify the use of the cold water because that is actually a pretty consistent temperature and the necessary heating times can then be set pretty reliably at the factory. On 110V you have to use hot water, and you have to make sure it’s actually hot in the pipes when the machine starts filling. The latter is obviously less desirable, but it’s the only way to get a proper wash out of 110V dishwashers. It’s a crapshoot, North Americans don’t generally know or do this, and the quality of the wash suffers accordingly. But they simply don’t make them any other way. Maybe they should change. But they haven’t. This is what we’re stuck with.
So basically if you have 110V dishwasher you need to hook it up to hot water and make sure the water gets hot before it fills if you expect them to wash properly. That’s just the reality of how they’re designed. 220V = cold water, 110V = hot water. That’s basically universal in the regions where each power standard is used. Unless you take a European/Asian 220V dishwasher and run the 220V wiring to hook it up in North America intentionally, but nobody actually does that, and you’re not going to find it was done in your house by surprise.
It really doesn’t have anything to do with 220v vs 120v systems. You can easily boil water with 15 amps at 120 volts. We used to have dishwashers with strong enough heating elements in the US to do this from cold running on 120v. It is a lot more to do with the efficiency standards set by Department of Energy, starting in 1994 and then further restricted in 2013 to maximum 307 KWh/year and 5 gallons of water per cycle. Prior to this, dishwashers in the US worked very differently than they do today. This is also why dishwashers in the US do a terrible job of drying dishes now - not enough energy to power a bigger heating element like they used to have.
On top of that, many current built and sold machines (at least in the US) are in fact more complicated than let on above, even the cheaper units, just not how you’d think. In order to try to squeeze as much performance out of those efficiency standards above, many have a turbidity sensor in the water flow path that checks how “dirty” the water is. If it doesn’t detect much, they will stop the cycle early, which means they “use less energy per year on average” (for the above legislation) and then can use more energy in a cycle “that needs it”. This often has a downside of people that significantly pre-rinse their dishes get really bad results from a dishwasher because the cycles will end so early the detergent hasn’t even fully dissolved yet and will be scattered and stuck to the dishes.
They are correct though that most don’t have temperature sensors in them, because frankly it doesn’t matter - they are either able to get to the needed temperature with the energy they are allowed or they aren’t. The only benefit of letting the machine know would be so it can display an error code to alert the user there is a water temperature problem (but most mfrs don’t want to do that because the average user won’t even bother looking up the error code and will just try to return the product or get a warranty service call, both of which cost the mfr money).
I can’t speak for outside the US, but in the US your dishwasher needs to be hooked up to a hot water line. The detergent won’t dissolve properly under 120ºF - 140ºF and they are restricted from using enough energy to get from “cold” to that temperature. Most of the manufacturers will even print in the manual that the water temperature coming in needs to be 120ºF so it can get hot enough to perform all functions.
If you hook up a US residential dishwasher to a cold supply line, you will be hand-washing all of your dishes.
Outside the us a lot of us have 230V power, so all of the dishwashers I’ve ever seen have their own heater and only hook up to cold.