Can You Run the Dishwasher with No Hot Water?!?

A dishwasher is one of the most integral pieces of kitchen equipment in today’s homes.

However, many folks, especially first-time owners, wonder what they’d do if it ran out of hot water.

The sheer thought of it can be scary to some, but it’s worth investigating.

Hence, Can You Run the Dishwasher with No Hot Water?

Yes, but it can depend on the age of the machine. It may also depend on how cold your water is. Most modern dishwashers aren’t too particular with temperature – they will scrub your dishes clean with water as ‘cold’ as 120 °F (that’s the coldest you could go in most cases) but some may tolerate slightly lower temperatures than this albeit with a warning.

But why don’t most modern dishwashers sulk at cold water as their older counterparts? Well, the secret is in their design.

Most of the latest dishwashers you will find in the store are equipped with a circular heating component often at the bottom.

The component is designed to receive water at considerably low temperatures (by dish-scrubbing standards), and heat it to a certain point if it’s found to be cold.

Generally, older and some select-few modern units will heat your water to between 140°F (60°C) – 150°F (65°C) if they receive it at about 120°F (or 48°C).

Why do some machines insist on 120°F (or 48°C) and even display a warning before heating it further?

It’s because the colder the incoming water the longer the machine takes to hit the recommended scrubbing temperature. So this is good for both your electricity bills and durability.

Does It Mean Cold Water Can Be Bad for Your Dishwasher?

More precisely, can you hurt the machine with cold water?

In one word – “No.” Coldwater won’t ruin your dishwasher, but will certainly affect its performance.

There’s a simple explanation: hot water is better at killing germs and melting the grease off your dishes than cold water.

If you use cold water on dishes that served beef stew, the familiar disgusting smell and leftover oil will stay put no matter the kind of detergent you use.

The dishwasher, however, will keep doing its job for longer until it runs down its factory lifespan.

What If You Use Very Cold Water?

As mentioned earlier, you are free to use water under 120°F but only with a more modern dishwasher.

If you add cold water in a newer model, it will automatically check the temperature and turn on the heating element to increase the temperature to recommended levels.

However, to reach the ‘scrubbing temperature,’ extra energy will be required.

This means that the more often you use cold water the more you will bloat your electricity bills.

Electricity bill aside, you also need to worry about the general lifespan of the machine because it’s basically overworking.

So, if you live in an area with access to water under 120°F only, consider linking your hot water supply line to your dishwasher.

Some modern dishwashers are made in such a way that they allow the user to switch between the internal heating element (which heats water internally) and your household hot water supply.

Whether or not your dishwasher supports this function should be outlined in the user manual that came with it.

If it permits it, you will need to use a purpose-built hot fill hose which is different from the cold water hose, two of which shouldn’t be used interchangeably.

Therefore, if your home is serviced with a hot water line (you have a water heater, for example) complete with a manual temperature setting as usual, and you want to use it to feed your dishwasher, the wisest thing you could do is shop for the dishwasher that will work flawlessly with it.

That’s because dishwashers are not made the same – you need to find a design that works with your plumbing and manual temperature setting.

Of course, other preferences have to be factored in as well.

Okay, So It’s a Great Idea to Add Your Hot Water Manually, Right?

Yes, certainly. Be careful though.

First off, if you have a stable and efficient hot water supply line at home, this might end up being the best dishwashing decision you will ever make.

Since you will be restricted to an external hot water supply, it only makes sense that you choose a machine equipped with no heating element because it won’t heat water internally.

Dishwashers with no heating element and thermostat are cheap and won’t bloat your electricity bills.

You need to be a little careful regarding water temperature.

Because you are linking your dishwasher directly to the external water intake, you should adhere to the temperature prescribed by the manufacturer.

The typical limit is 170°F beyond which you could blow up your dishwasher.

Fortunately, some modern machines can stand up to great temperatures but consider reading and understanding the accompanying instructions first before anything.

Does It Mean Dishwashers Are Hot Water Guzzlers?

Yes, unfortunately. A typical dishwasher happily gulps down 6 – 8 gal. of water in every passing cycle. About 2 – 3 gal. of it is hot.

Some brands take even more hot water to scrub your dishes.

Intricate machines come with a costly price tag but are using less water and electrical power.

By the end of a single cycle, about half of your water will be hot, ready for the following steps.

If you are nervous about the potential impact on your electricity bill, read the manual several times to fully understand what you are just about to install.

Oftentimes, heating 2 – 3 gal. to anything between 150 – 160°F can be burdensome to your machine.

Don’t be surprised if burns through 1000 BTUs and bloat your electricity bill to a figure you’ve never seen before.

What Are the Other Setbacks of Linking Your Dishwasher to Your Hot Water Supply?

There are several cons to connecting your machine to the main hot water system.

If water is allowed to flow into the dishwasher at temperatures over140°F (60°C), it may ruin the inbuilt filtration unit.

In such a situation, therefore, refrain from drawing hot water from an external source.

Why Is My Dishwasher Water Cold?

If your dishwasher is connected to an external water heater, the problem may be somewhere along with the hose or the main source has run out of hot water.

If your machine is connected to a cold water source and is internally heated, chances are the heating component is faulty.

If the heating element is found to be working perfectly, check the thermostat.

If the thermostat and the heating component are working as expected, try to adjust to the hottest heating program. One of the four points is more likely to be faulty.


So, can you run the dishwasher with no hot water?

Yes, certainly, but it can depend on the age of the machine. It may also depend on how cold your water is.

Most modern dishwashers aren’t too particular with temperature – they will scrub your dishes clean with water as ‘cold’ as 120 °F (that’s the coldest you could go in most cases) but some may tolerate slightly lower temperatures than this albeit with a warning.