Do Dishwashers Use Hot or Cold Water? (Explained)

Dishwashers can now be found in almost every home. It has become a necessity because it saves you time and effort. Cleaning dishes by hand can feel like a boring and tiresome chore, especially if you have a large family.

They can look complicated to install but ever wonder if they are connected to hot or cold water? Let’s find out! 

Do dishwashers use hot or cold water?

Whether dishwashers use hot or cold water depends on the brand, model, and water supply line. Many dishwashers only use hot water from a hot water supply line. Some come with a heating element that does not require a hot water supply. The temperature is usually written in the product description. 

Do you connect a dishwasher to hot or cold water?

Some dishwasher brands specifically design dishwashers for hot water and vice versa. On the other hand, some dishwashers can be connected to either hot or cold water. It varies from model to model.

You should always check the manufacturer’s manual for instructions on whether to connect it to a hot water supply line or a cold water supply line. Dishwashers are typically connected to cold water because they come with an internal heater.

Many prefer to connect it to hot water to clean debris faster and make drying simpler. If your dishwasher comes with an internal heater then you do not need to hook up to a hot water tap.

The internal heater will reach the required temperature on its own. There are also dishwashers that can be installed to both hot and cold water at the same time. This is only applicable for dishwashers with two inlet hoses. 

The water supply line of your building also matters. If the hot water supply has a temperature of over 149 degrees Fahrenheit and cannot be lowered, then you have to hook up your dishwasher to cold water. Temperatures exceeding that level can be dangerous. 

Do dishwashers use hot water or heat their own?

Only the dishwashers that come with a heating element, heat on their own. They are typically connected to a cold water supply line and heat the water before the cleaning process starts.

There are some exceptions such as the Whirlpool dishwasher that comes with a heating element and is recommended to be hooked up to a hot water line. The temperature can sometimes be adjusted as well. 

Do all dishwashers heat the water?

Not all dishwashers heat the water. Only modern dishwasher models have the heating element. The heating element is a fairly new technological advancement. 

Old dishwasher models did not come with a heating element or heater, they were only used using a hot water connection. The temperature is not adjustable either with those dishwashers. 

Will a dishwasher work without hot water?

You can use your dishwasher without hot water because almost all dishwashers come with a heating element at the bottom of the tub. The regular water or cold water can be turned hot with the help of the heating element. 

However, this only applies to newer models of dishwashers. 

Old dishwasher models cannot function without a hot water connection. So if you have an old dishwasher, maybe it is time for an upgrade! There are some disadvantages of using cold water as well which we will soon learn. 

Is it OK to run a dishwasher with cold water?

It is completely fine to run a dishwasher with cold water since the majority of dishwashers have a heating element. Even if it does not have a heating element, you can run a dishwasher using only cold water. It will not harm or damage your dishwasher nor your dishes. 

Very cold water might not be good to use because once the dishwasher tries to heat the cold water, it will take up more energy to heat it. This will raise your utility bills. It might shorten the lifespan of your appliance too. 

Why is it better to use hot water in a dishwasher rather than cold?

Following reasons make hot water better in a dishwasher –

Hot water is better for cleaning:

Residues and grime left on the dishes are easier to clean with hot water than cold water. Washing with cold water might leave some sort of residue behind and also take more time to clean. 

Reduces bacteria and other microorganisms:

Hot water is better for removing germs and other bacteria. Overall, hot water does a better job of disinfecting and cleaning than cold water. This is mainly why dishwashers were initially designed to be only connected to hot water lines. 

Makes rinsing easier:

During the rinsing phase, the temperature of the water usually rises in dishwashers. This leaves your dishes hot, making the water dry up more quickly. If you use cold water to wash the dishes, it will take longer to dry up. 

What is the best temp for a dishwasher?

The ideal temperature for a dishwasher is set by its manufacturer. On average, you can expect the best temperature for your dishwasher to be over 130 or 140 degrees Fahrenheit. 

Although 120 degrees Fahrenheit should be enough in the case of most dishwashers, many prefer to go higher. The temperature also differs according to the step. During the rinsing process, the temperature goes higher around 180 degrees Fahrenheit. 

If you’re unsure about the correct temperature, check the manufacturer’s manual. Anything around 120 F and 150 F should be fine for the efficiency of your dishwasher. 

Can you use your dishwasher if your hot water heater is broken?

You can use your dishwasher if your hot water heater is broken. You will have to provide the hot water supply manually in this case. Older dishwasher models did not come with a thermostat or hot water heater. 

If your water heater is broken, connect your dishwasher to a hot water line so that it can receive water directly. Do not use the direct hot water line if your hot water rises to unsafe levels.

How can I tell if my dishwasher is using hot water?

If you’re not sure if your dishwasher is connected to hot water or cold water, check the temperature of the water. You can do this by using a thermometer such as a meat or candy thermometer. 

Your water temperature should be over 110 degrees Fahrenheit. Another simple way to find out if your dishwasher is using hot water is by observing your dishes. As mentioned earlier, hot water dissolves residues from the dishes faster than cold water. 

If you notice that your dishes are not as clean as before, the temperature might have dropped. 

Why is my dishwasher only using cold water and not getting hot water?

If your dishwasher is only using cold water or not getting hot water properly, it could be an issue with the heating element or thermostat. Many things could happen such as defective wiring, broken thermostat. To find out if they are working, use a multimeter. 

If both of those things are working properly, check wire connections and the control board. 

Does a dishwasher need its own water supply?

Yes, most dishwashers need their own water supply. You can use the water supply that’s available under the sink. It often comes with a hose that facilitates the connection to the water supply under the sink. 

Some valves cannot connect both the sink and dishwasher to the same water supply source. For this reason, you will need to purchase an angle stop. This valve comes with two outlets that connect it both to the sink and the dishwasher. 

Final thoughts:

Dishwashers can be connected to both hot or cold water but it is up to your manufacturer or model. Dishwashers only use hot water to clean. Older models tend to be connected to hot water only whereas modern ones are connected to cold water only or both.