Warm Water Bidets Explained (Electric and Non-Electric)

Today’s question asks how warm water bidets work. There are lots of features that set electric bidets apart from the rest and warm water is probably the most important. Though, as we’ll see, non-electric bidets can provide warm water too if certain plumbing attachments are used.

Not only does warm water feel better, but you get a more thorough clean because washing with warm water helps liberate oils from the skin that harbor bacteria.

How Do Warm Water Bidets Work?

Warm water bidets either work via electricity or with the home’s hot water supply. Electric bidets heat water in a reservoir, heat it instantaneously, or use a combination of the two technologies. With extra parts (e.g., mixing valve), non-electric bidets and handheld sprayers can provide warm water.

What we’ll do here is take a closer look into the different ways bidets heat water and the pros and cons of each method.

Because folks often ask about non-electric bidets—specifically handheld sprayers—we’ll be covering these in detail too. In doing so, we’ll look at some of the drawbacks of using hot water with non-electric bidets.

Here’s a quick summary.

These are what most people think of as warm water bidets.

These exist, but are less common (for several reasons, most non-electric bidets are cold only).

How Do Electric Bidets Get Warm Water?

Electric bidets, the most common category of bidets that use warm water, heat the water up in three different ways depending on the model:

  • Heated reservoir type. The most common and economical.
  • Continuous type. Common on fancier models and allows for unlimited warm water flow.
  • Hybrid type. A combination of the two.
An Illustration of the 3 Main Bidet Water Heater Mechanisms. Inspired by Many Bidets Illustration

Heated Reservoir Type

These are the most common because they’re the cheapest of the three and hence can be added to most bidets in the $200-400 price range—a price range that’s typical for bidet seats.

These are great to start out with, especially for those who are new to the idea of using bidets and are perhaps too skeptical to put down a lot of money for a pricier luxury model right off the bat.

Models vary but the typical temperature range is between 95 and 105°F (or 35 to 40 °C).

The pros:

  • Best value. Electric bidets that contain the heated reservoir type are typically the most affordable electric units. They are a huge step up from non-electric models. While non-electric attachments and sprayers can be found for less than $50 they only clean with cold (typically unfiltered) water.
  • They usually get the job done. The amount of warm water supplied for one session is enough for most bowel movements.
  • No permanent alterations to the property are needed. This is true of ALL electric bidets.


  • The potential to run out of water mid-wash. Most reservoir-type heaters will supply a stream of warm water for a minute or so. It varies by model but the heater usually works for half a minute heating the water sufficiently for it to run warm for another 30 seconds. No one likes to run out of water mid bath and your butt won’t appreciate it either. But, keep in mind that most find a minute of warm water to be plenty sufficient for most bowel movements.
  • Perhaps less than ideal for feminine washing. Not all bidet seats have a frontal wash mode but it’s a pretty common feature—not as common as it should be given that half of all adult consumers are women. In the event you’re looking to get a bidet for feminine hygiene, some protocols (especially douching) call for several minutes. In this case, a bidet seat with a reservoir-type heater probably isn’t ideal if warm water is a deal-breaker for the user.
  • Sloped seat. A reservoir-type heater needs to store sufficient water to supply a 1-minute stream. This means it takes up more space in a toilet seat that already houses other sophisticated technology. This accounts for why a lot of bidet seats are raised in the back and slope down to the front (see the above image). Some find this to be uncomfortable because it requires you to sit further forward on the seat. It can also be an aesthetic issue. While most consider them to be quite stylish, this type of electric bidet isn’t as low profile as some of the more expensive seats.
  • Higher energy needs. These work kind of like those commercial coffee makers at most restaurants that keep warm water on tap. That way you don’t have to wait long for a cup to brew. The constant water heating is great in that hot water is ready on demand, but it also means that the heater will be using some amount of electricity 24/7.

If you think you’ll be needing longer wash sessions (longer than a minute) keep in mind that warm water isn’t necessary to get a good clean that far surpasses anything offered by toilet paper.

Instantaneous-Type Water Heaters

These come on most of the higher-end electric seats. In my experience, they start showing up in models that are in the range of $700 or more because they’re considered luxury bidets. Some top-shelf luxury bidets are quite affordable. For more info, check out the article on the best bidets with tankless water heaters.

I’m sure technology can vary, but tankless water heaters usually consist of a series of coils that heat water instantly as it flows through a vessel.

Electrical current is automatically applied to the coils on-demand as hot water is requested. Hence, this kind has the added benefit of saving on power as electrical current isn’t applied when not in use.

The pros:

  • Unlimited warm water. This type of heater uses sophisticated technology that heats water up on the spot. That means no running out when you’re in the middle of a cleaning session. Again, most users do just fine with a minute of warm water—it’s more than enough for me. But, it’s nice to know you’ll never run out.
  • Great for shared bathrooms. Even if you get by just fine with a minute of warm water, you may need to consider getting a model with a continuous-type heater if you share bathrooms. In this way, you’ll always have enough warm water to go around and it won’t matter how long it’s been since the bidet was last used.
  • Great for frontal washing and feminine hygiene. While you won’t need any more time for frontal cleansing compared to posterior cleaning, having unlimited warm water means you can clean both in the same session. Just make sure to get a bidet with a feminine wash mode or at least one that offers frontal spraying. Also, having more warm water means you’ll be able to perform deeper cleaning sessions that take longer.
  • Sleek, comfortable design. Because there’s no need for housing a big water reservoir, these tend to have a flat surface (no sloping). If you want a bidet that doesn’t look like a bidet, then you need a model with a continuous-type heater.
  • Lower energy costs. Unlike with reservoir-type heaters, there’s no wasting energy to heat water around the clock when you only need the water a few times per day.
  • Rental property friendly.


  • Price. Because it’s fancier, this type of technology tends to be used in bidets that are fancier overall. While most features offered by electric bidets can be found in non-luxury models, the higher-end seats have a few unique and useful functions (self-cleaning bowls, frontal wash mode, heated seats, etc.). Hence, the higher price tag.

Hybrid-Type Water Heaters

Hybrid water heaters are a hybrid of technology and price.

However, they’re not much of a hybrid in terms of functionality. They typically offer only half a minute extra at most.

If you’re worried a minute of warm water may not be sufficient for you, then it probably won’t put your mind at too much ease opting for a model that only adds 20 to 30 seconds.

As you’d imagine, this kind makes use of a mechanism that’s a hybrid between the reservoir and instantaneous heaters mentioned above.

They keep warm water on tap which means less energy will be needed to heat water up on the spot when in use.

In terms of price, models that have hybrid heaters tend to be somewhere in the middle. IMO, it may not be a good compromise, because paying extra might not make sense if you’re only getting a few more seconds of warm water.

Because they use a smaller reservoir of water, bidets with this kind of heater aren’t likely to slope as much, which may or may not be a benefit depending on your preferences.

While they’re usually not much better than regular reservoir-type heaters, exceptions do exist.

On average, this kind of heater doesn’t add too much value. However, some heaters of this kind put out more warm water and I can think of one that offers unlimited warm water.

The one and only model I’ve found so far that claims to offer unlimited warm water via a hybrid heating technology is the Bio Bidet 2000.

I’ve recommended the BB 2000 in several posts for those who want as many features as possible without breaking the bank—it’s quite inexpensive. It even has a feminine wash mode, a feature lacking in some higher-end seats.

How Do Non-Electric Bidets Get Warm Water?

Non-Electric Bidets. Non-electric seats exist too but they’re less popular than attachments.

Yes, non-electric bidets can provide warm water.

Interestingly, I’ve found that people either assume non-electric models can provide warm water or they assume that this type of bidet is doomed to use cold water forever by default.

Non-electric bidets can provide warm water via special equipment that allows access to the home’s warm water supply. Some connect to the bathroom sink hot water shutoff valve and others directly to the faucet. Finally, some equipment allows for direct access to the plumbing.

Warm water handheld bidets hook up to the faucet or are plumbed into the home’s hot water supply (e.g., the TRUSTMI bidet).

Warm water bidet attachments and non-electric seats use the sink shutoff valve method.

A warm water non-electric bidet attachment.
A bidet attachment connected to the warm water shutoff valve at the bathroom sink.

Warm water non-electric bidets come with a few drawbacks:

  • Permanent alteration of the property. To solve the above problem, some bidets have special plumbing equipment that allows you to hook the bidet directly to the warm water supply lines. However, it often requires that you drill into the property, usually the vanity, and that you tamper with the existing plumbing. This is off-limits for renters unless express permission is obtained from the property owner.
  • Some are more expensive (warm water handheld sprayers). This isn’t always the case, but the kind that connect into the home’s plumbing can be a bit more expensive. For example, the TRUSTMI handheld sprayer is about $70, when most sprayers are around $30. Add to that the cost of the plumber needed to install the bidet, and you probably won’t be spending much less than you would if you just went for the electric bidet seat. Obviously, this won’t apply to those who have the know-how to install one on their own.
  • The kind that connect to the faucet require constant fiddling with the bidet. Handheld bidets are usually set up via a simple 10-minute installation process. You set it and forget it. However, some models come with warm water connectors that allow you to attach the supply hose to the faucet. This requires constantly “installing” the bidet, i.e. hooking it up with each use. Either that or having a dedicated sink—something that’s impractical for most bathrooms. Even if you have two sinks, the other is probably in use if you’re sharing bathrooms.

How Do Bidets Get Warm Water? Conclusion

So, there you have it.

Electric bidets get warm water by using integral water heaters, while non-electric units and handheld sprayers require extra parts to allow sourcing warm water from the home’s hot water lines. With the former, temperature is adjusted with a remote control, while the latter uses a mixer valve.

There are several mechanisms, both mechanical and electrical, that allow bidets to provide warm water.

Most warm water bidets are electric, but non-electric bidets compatible with warm water do exist.

Those that work via the home’s warm water lines have several drawbacks but offer a few advantages too.

For example, some people just like handheld bidets. Also, by tapping into the property’s hot water, you’ll never have to worry about running out of warm water mid-wash.

Plus, you’ll be paying a lot less for a sprayer or attachment compared to what you’d pay for a luxury bidet with a continuous-type water heater.

Using the faucet to get warm water means you’ll have to hook the bidet up with each use or go through a costly installation process.

Also, water from a faucet has to run a minute or so before it starts to warm up. By sourcing warm water from the sink, you’ll probably be done cleaning before the water starts to run warm.

Electric bidet seats are probably the most practical for the majority of consumers if warm water is a priority.

If you want an electric bidet and think your cleaning sessions might average more than a minute, you may want to consider a model with a continuous-type heater. If not, you should be just fine with a regular reservoir-style heater.

That’s it for now. Thanks for reading.

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