This is crazy to me. How do the dishwashers in US heat the water up hot enough to clean effectively? Our dishwashers heat the water up past scolding, really helps cleaning.
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kboy101222@lemm.ee 10 months agoWait, are hot water dish washers not a thing outside the US?
Fluid@aussie.zone 10 months ago
captain_aggravated@sh.itjust.works 10 months ago
Every dishwasher I’ve used in the United States has a built-in heating element. Mine has a steam sanitize function and gets quite hot.
However, it is conventional here to plumb the dishwasher to the hot water line, and it is my understanding that the dishwasher is designed to assume the water is hot and doesn’t try to heat it from cold during the first rinse.
I’ve found that running some water from my kitchen sink to prime the hot line with hot water makes the dishwasher more effective. I use that water for plants, or I keep it in a jug and pour it into a load of laundry in the winter.
Fluid@aussie.zone 10 months ago
Interesting, thanks for info!
S_204@lemmy.world 10 months ago
There’s a heating coil in the bottom of the unit. Water floods in and sits for a short while while reaching temperature.
Taringano@lemm.ee 10 months ago
I think it’s everywhere but in the US the water comes already hot, in Europe the dishwasher heats it up from the regular cold water.
Squizzy@lemmy.world 10 months ago
Yeah the hot water way seems better.
Mr_Blott@lemmy.world 10 months ago
It’s because our dishwashers are massively more efficient and environmentally friendly.
They use very little water, which they heat up themselves to save energy
The only drawback is they take longer to clean the dishes, up to three hours
But nobody would be so selfish as to demand their dishes be done quickly over preserving our environment, would they?
Nollij@sopuli.xyz 10 months ago
Why would that save energy? It’s going to be resistive heat, which at best matches the water heater. Some models in the US include a heating element, but it’s more of a convenience. The vast majority are simply connected to the hot water line, since that’s why it’s there.
Also, let’s talk numbers. From what I could Google, EU dishwashers use 1-1.5KWh/load, while US dishwashers use an average of 1.15KWh/load. Certainly there are more efficient models, but this shows that there isn’t a significant difference in energy usage between them.
Squizzy@lemmy.world 10 months ago
I’m confused, our as in European dishwashers are more efficient and environmentally friendly?
But wouldn’t it be even more so if the hot water that was stored and not being used was the feed instead of cold water? That was the temperature increase is minimal and a lot more efficient.
The eco wash is the best wash on my dishwasher.
Rivalarrival@lemmy.today 10 months ago
No.
The reason your dishwashers use cold water is because your hot water supply is not presumed to be potable water.
EU regulations allows for gravity-fed hot water tanks in certain jurisdictions, open to atmospheric pressure, and thus possible contamination. They did this to prevent the possibility of exploding boilers.
Since the building’s hot water supply is presumed unsafe, dishwashers are required to use the safe, cold water supply to generate their own safe, hot water.
US regulations do not allow hot water to be held at atmospheric pressure. We use T&P valves to limit boiler pressures and prevent explosions. Our hot water is not exposed to environmental contaminants, and is presumed potable.
theragu40@lemmy.world 10 months ago
I’m so confused. Whose dishwashers are you talking about? I’m in the US, you’re describing every dishwasher I’ve ever had, except that we always hook it up to the hot water line. Our unit takes very little water, it takes hours to run a load due to efficiency features. It has a heating element inside to take whatever water it gets and keep it hot for the cycle.
I don’t really see why it’s any less efficient to use the hot water we are already heating with our water heater (which heats much more efficiently than a small electric heater would). The water originally arrives to my house cold, it has to be heated one way or another. My dishwasher is less than 10 feet away from my water heater, water is not losing appreciable heat on the way to the dishwasher.
sunbeam60@lemmy.one 10 months ago
It depends. Spraying your dishes with water that is prone to legionella doesn’t seem super safe to me. But even assuming that, I have dishwasher programs than run at 70C, which is above what my hot water tank produces.
Besides, isn’t there a heating element in a US dishwasher regardless? Otherwise, it feels like it has got to continually add more hot water to keep the temperature up…
Rivalarrival@lemmy.today 10 months ago
That is the real reason why UK / EU dishwashers use the cold water supply. They don’t consider a building’s hot water supply to be potable water. Their hot water was once held in atmospheric pressure, gravity-fed tanks, exposed to environmental contamination. Brits treated central hot water as unclean. This is also why they often used separate taps for hot and cold water. If they need clean, hot water, they heat cold water at the point of use.
The US never allowed atmospheric pressure hot water tanks. Our hot water is not exposed to environmental contaminants, and is presumed potable.
Taringano@lemm.ee 10 months ago
I believe it’s mostly due to not having always hot water hookups available where laundry would be or not consistently having hot water always available. (as in on demand, from a large boiler that wouldn’t impact the remain of the hot water uses)
sunbeam60@lemmy.one 10 months ago
Yes in many places, hot water is produced on demand in smaller residences. This means your dishwasher relying on hot water would kill your shower.
I know this seems odd probably to Americans … but many houses in the U.K. doesn’t have the space for a hot water tank.
Zron@lemmy.world 10 months ago
That seems way less efficient and more prone to issue than just having a central appliance that’s responsible for making hot water.
Mamertine@lemmy.world 10 months ago
It is, but the dishwasher has to have a water heater in it. It has to heat water to a temp that you shouldn’t keep you got water tank at and heats throughout the cycle.
Your clothes washer (generally) also has a built in water heater.
Squizzy@lemmy.world 10 months ago
My tank is 60° and my washing machine is 40° and dishwasher is 70° at a maximum. A lot more efficient to have a hot water feed to these that have them increase the temperature 30-50°.
Peppycito@sh.itjust.works 10 months ago
Dump a kettle of boiling water in the dishwasher before you start the cycle.
burrito@sh.itjust.works 10 months ago
That wouldn’t work with every dishwasher I’ve ever had. They all start the cycle by draining any liquid in the dishwasher before they fill to run the first pre-wash cycle.
Peppycito@sh.itjust.works 10 months ago
Oh. Admitably I’m not an expert, I’m still ony first ever dishwasher. I did that when our water heater died and it seemed to help.