Run a Portable Dishwasher Overnight – Or Not?

There’s no denying the convenience of portable dishwashers, from not having to hand-wash dishes to being space savers and not requiring permanent hook-ups. With the increasing use of electrical appliances overnight, you might wonder, ‘Can you run a portable dishwasher overnight?’

As convenient as it may seem to leave your portable dishwasher running overnight, it isn’t recommended to do so owing to its several associated risks.

However, a few measures can ensure safe operation if you must leave it running overnight or unattended.

Can You Run a Portable Dishwasher Overnight?

It’s best to avoid running your portable dishwasher overnight, but if necessary, you may do so if the setting is stable and doesn’t need any changes. A portable dishwasher that automatically turns off and opens the door at the end of the wash cycle is a safer option.

Nevertheless, the hook-up of a portable machine isn’t as stable as regular dishwashers.

A standard built-in dishwasher has permanent connections. The water supply hose is securely connected to a water supply shut-off valve under the kitchen sink. The drain hose is usually connected to the garbage disposal or the sink drain tailpiece.

On the other hand, portable models (free-standing or countertops) don’t need permanent plumbing connections. They’re typically designed with an adapter hose that temporarily attaches to your kitchen sink faucet for water supply and a drain hose that drains the dirty water into the sink.

These temporary hook-ups may lead to some problems.

  1. Drain pipe misplacement – Unless you securely clamp the drain hose, the pressure of the draining water might misplace its position out of the sink. It will cause the dirty water to spill out, creating a mess.
  2. Leaks – There are chances of leaks from the point of the sink faucet connection, the water inlet fitting of the dishwasher, or the appliance itself.
  3. Pressure build-up leading to faucet damage – Although rare, leaving the water supply longer might cause pressure build-up after the dishwasher cycle. This might damage the faucet or the dishwasher hose.

Above all, dishwashers consume ample energy and generate heat. There’s the possibility of a malfunction in the machine which may result in a fire hazard.

7 Risks of Leaving a Portable Dishwasher Unattended

Here are some risks of running a portable dishwasher overnight or leaving it unattended.

1. Faucet Connection

With temporary hook-ups, there’s the chance you didn’t check the faucet connection properly before turning on the dishwasher (or setting a delayed start).

If it isn’t securely connected, the water pressure may cause kinking, leading to an increased pressure build-up in the hose. Eventually, the hose will pop off. 

Not only will your dishwasher not receive a water supply to wash the dishes, but the water will also keep running overnight from the faucet (water wastage and increased water utility bill).

2. Water Drain

Any issues with the drain pump, drain hose, and the motor that fails to provide power to the pump could result in the dishwasher failing to drain water appropriately. As a result, the dishwasher may start leaking water, leading to a flooded floor overnight.

Also, if you place the drain hose unclamped in the sink, it might move out of place, draining water all over the kitchen floor (and counter) instead of the sink.

More about how portable dishwashers drain.

3. Malfunction

Sometimes, internal components malfunction and need to be replaced. The problem with running the appliance at night is any malfunction (due to a faulty circuit board, leaky hose or pump, broken heating element, etc.) may go unnoticed.

While this might cause problems like leaks or dishes not being washed properly, the worst-case scenario is if a fire breaks out.

4. Leakage

In the event of leaks due to a leaking water supply line, drain line, damaged latch, soiled or damaged door gasket, or a damaged component, you’ll wake up to water puddles or a flooded kitchen floor.

5. Humidity

When you run your portable dishwasher, it often adds humidity back into the house. On hot days, this will have you turning on the air conditioner and increasing energy consumption.

Besides, without proper ventilation, the increase in humidity levels eventually causes mold and mildew problems.

6. Wrong Usage

Incorrect usage, like overloading the dishwasher, dishes interfering with the spinning action, and loading plates without scraping food chunks can result in your dishes not being cleaned properly after running it overnight. 

However, occasionally, your dishwasher may leak due to using the wrong detergent (which causes excessive suds to overflow from the unit).

Also, without regular maintenance, your dishwasher may malfunction anytime, even when run overnight.

Find out how to run a portable dishwasher correctly.

7. Application Error

Typically, dishwashers are programmed to display fault codes or error codes when they encounter any issues. Most of these error codes are issues you can resolve by yourself, while some need a technician.

When you run your portable dishwasher overnight, any application error code (if one comes up) will go unresolved. Consequently, the appliance won’t be able to get the job done.

The faults can range from issues pertaining to draining, water inlet, pressure, and temperature to power failure and leaks.

Yet another fault is an open/short circuit of the thermistor or temperature sensor that could possibly lead to appliance damage.

4 Reasons You May Run It Unattended

Here are some reasons you might want to run your portable dishwasher unattended or overnight.

1. Lower Energy Costs

Most energy providers charge high rates for energy used during peak hours of the day. However, if you run your appliance in the off-peak hours (mostly at night), you can save money on your utility bills in the long run.

Since peak hours and rates vary depending on the energy provider and area, it would help to have this information beforehand.

2. Noise Won’t Be a Bother

Most portable dishwashers have a noise level of 50-60 dB. Unless you own one of the newer dishwasher models with lower noise levels, the noise from the appliance could be a bother during the daytime.

If you run the wash cycle overnight, since nobody will be around the kitchen, the appliance noise won’t be a disruption.

3. Use Kitchen Space When Not Needed

Portable dishwashers (especially the free-standing models on wheels) serve as space savers. You can roll one into a corner when not in use and bring it out to temporarily hook up near a sink to wash dishes.

If you’re tight on kitchen floor space, you can run the dishwasher at night when the kitchen space isn’t being used. And then, you can roll it back to its storage space in the morning.

4. Busy Schedules

Those who rush to work in the morning and return home late have no time to tend to household chores (including washing dishes) during the day.

You can consider running your portable dishwasher overnight if you have a busy work schedule. Before you get to work in the morning, you can remove the dishes and keep them in place.

How To Leave a Portable Dishwasher Running (If Necessary)

If you absolutely must leave your portable dishwasher running overnight or unattended, there are a few things you can do to ensure a sufficiently safe operation.

  • Recheck all the connections:
    Ensure the water supply hose is tightly attached to the sink faucet, isn’t bent, and the water pressure is sufficient. Also, ensure the drain has no kinks. Check the connections on the dishwasher as well.
  • Check the water hoses:
    Keep an eye out for any damaged water hoses that might cause leaks.
  • Secure hoses with additional methods:
    While the inlet hose connection requires only the right-sized adapter, you can use a hose clamp to secure the drain pipe from falling to the floor.
  • Ensure the dishwasher stand is secure:
    The stand (especially the ones with wheels) must be sturdy, steady, and level so that the dishwasher is level and stable.
  • Use a water sensor:
    Water leak detectors or water sensors detect water in locations where there shouldn’t be any and triggers an alarm or warning signal. This helps avoid excess water leaks and property damage.
  • Functional fire alarms:
    Where there are electrical appliances, there’s the chance of a rare fire. Regardless of whether running your dishwasher overnight or during the day, ensure you have functional fire alarms.


While it might seem like a good idea to run your portable dishwasher overnight, it’s advisable not to do so.

With the possibility of leaks, malfunction, increased humidity, and fire, the associated risks outweigh the benefits of running your dishwasher unattended.

However, if you must, it’s best to properly check the connections, hoses, and dishwasher stand while also ensuring you have functional fire alarms and a water alarm (for leaks).