RV Toilets Compared: Dometic 310 vs Dometic 320

When you have to go, you have to go. It may not be the stuff of polite conversation, but it is a fact of life. Everyone needs to use the toilet.

One of the great advantages of RV travel is that you have your own bathroom with you wherever you go. Not all RV toilets are the same, however, and there is a surprisingly wide range of options available.

Dometic makes some of the most popular RV toilets on the market, including the Dometic 310 and the Dometic 320. So how do you decide which of these best-selling models is right for you and your rig?

Bottom Line Up Front Summary: If you are choosing between the Dometic 310 and the Dometic 320, the 320 is my recommended model, but measure carefully and be sure that it will work in your space. If it doesn’t fit, the 310 model is still a great choice.

The Main Differences Between the Dometic 310 and 320

The main differences between the Dometic 310 and the Dometic 320 are:

  • The Dometic 320 has an elongated seat and deep bowl for a more comfortable and residential feel, whereas the Dometic 310 has a smaller size typically associated with RV toilets.
  • The Dometic 320 comes with an enameled wood seat that is sturdy and comfortable, whereas the Dometic 310 comes with a plastic seat that is far less durable.
  • The Dometic 320 has a pressurized full-rim and low flush design that uses less water, whereas the Dometic 310 has a rimless 360° vortex flush pattern to rinse the bowl thoroughly.
  • The Dometic 320 is large and heavy, whereas the Dometic 310 is much lighter and requires less space.

Seat Size and Bowl Depth

The Dometic 320 toilet has an elongated seat and a deeper bowl, giving you the look and feel of a residential toilet. For some, the difference between the smaller Dometic 310 and the larger 320 might not seem that important.

Most people will find the elongated seat more comfortable, but those who are larger or heavier will feel more relaxed and secure using the 320. The depth of the 320’s bowl is a particular advantage for men, who may find that certain parts of their anatomy touch the inside of the bowl when seated on the 310. 

Seat size and bowl depth have little effect on the functionality of the toilet. The bowl of the 310 is not so small that you would risk overflowing it with normal use. The importance of the elongated seat and deeper bowl will depend on who is using the toilet. An averaged-sized woman may not notice any significant difference, while a tall man will be far more comfortable on the Dometic 320.

Recommended Pick
Dometic 320 Toilet | Camping World

The Dometic 320 toilet is our TOP CHOICE. It has an elongated seat and a deeper bowl, giving you the look and feel of a residential toilet.

Buy at Amazon.com Check Price on Camping World
We earn a commission if you click this link and make a purchase at no additional cost to you.
02/18/2024 04:08 am GMT

Comfort on the Throne

Another factor that affects the comfort of your RV toilet is the type of seat. The Dometic 320 is aimed at having a residential feel on an RV toilet, and the seat is a feature that contributes to this. The enameled wooden seat on the 320 is sturdy and durable.

The Dometic 310 toilet comes standard with a thin plastic seat. This seat is lightweight but flimsy and not very comfortable. It is also prone to scratching and other cosmetic damage as a result of regular use.

The poor quality of the seat that is included on the Dometic 310 is a disadvantage, but upgraded seats can be purchased separately for $30-$50 that are comparable in comfort and durability to the standard Dometic 320 seat.

Flush Design and Water Usage

Another way the Dometic 310 and 320 toilets differ is in their flush design and water usage. Both are gravity-flush toilets that are flushed with a hygienic foot pedal which allows you to add water as needed. The 310 uses a vortex flush pattern for a rimless, 360° flush, while the 320 has a full-rim flush that is pressurized to create an effective flush with less water. 

There are advantages and disadvantages to both. The 310’s rimless bowl is easy to clean and the vortex flush pattern is very effective. The full-rim on the 320 is harder to keep clean but may prevent splashing. The efficient pressurized design means you can flush with as little as one pint of water.

For typical use in a campground with full hookups, the difference in flush design and water usage will not be noticeable. RVers who often choose to boondock, or dry camp, are more concerned with conserving freshwater and maximizing black tank space. If this is a priority for you, then the 320 might be a better choice.

Space and Weight Matter

Ultimately, the key factor in choosing an RV toilet may come down to size. The extra features of the Dometic 320 make this toilet much bigger and heavier than the Dometic 310. From another perspective, the areas where the 310 model seems to sacrifice comfort and quality result in significant space and weight reductions. Given the closet-like size of most RV bathrooms, these differences are important.

Weight is a consideration. Whether your RV is drivable or towable, staying within the proper weight range is important for safety. It may not seem significant that the 320 weighs in at 37 pounds while the much lighter 310 weighs only 23 pounds, but if you are already operating with narrow margins, those 14 pounds make a difference.

It is the overall dimensions, however, that could be the deciding factor. Be sure to measure the distance from the wall to the center of your flange (the hole in the floor that drains the toilet into the black tank).

The 320 needs 11 inches of clearance here, whereas the 310 only needs 10 inches. It’s amazing the difference an inch can make. Check all other dimensions as well to be sure that the toilet you choose will fit in your rig’s bathroom.

If you want to know How to find the Best RV Toilet, check out here all the types, what to look for, and how to make the right choice!

Additional Accessories

Generally, when you purchase the Dometic 320, all accessories are included. The manufacturer does not list any additional accessories for purchase, as the toilet comes with a top-of-the-line seat and is usually sold together with a hand sprayer to help clean and rinse the toilet.

RVers who choose the Dometic 310 can choose to upgrade the standard seat that comes with the product, and a hand sprayer can also be purchased separately and added to the 310 models. 

The hand sprayer can be mounted to the wall beside the toilet and used to help clean the toilet bowl as needed. Users more commonly report needing the sprayer on the 320 model, likely due to its water-saving flush design. 

Dometic 310 Toilet | Camping World

The Dometic 310 Toilet is a good option for smaller spaces. It has a lightweight design with a rimless 360° vortex flush pattern to rinse the bowl thoroughly.

Buy at Amazon.com Check price on Camping World
We earn a commission if you click this link and make a purchase at no additional cost to you.
02/18/2024 10:01 am GMT

Dometic 310 vs. 320: Installation 

There is little difference in installation between the Dometic 310 and the Dometic 320. Installation of your new toilet can be completed in a few simple steps with help from the owner’s manual.

There are also many helpful videos available on YouTube so you can see it being done before attempting it. If you are uncomfortable installing the toilet yourself, call a mobile RV technician to come to your rig and do it for you.

If you have measured carefully before purchasing to be sure your new toilet fits well in your bathroom, then the installation is relatively quick and easy. Be sure the water supply is turned off. After safely removing your old toilet, line up the new toilet over the floor flange.

The floor flange seal should already be installed in the toilet’s base, but verify this first. Note that if you are replacing the floor flange, do this after removing the old toilet and before installing the new one. Align the holes for the bolts and bolt the toilet in place.

Connect the water supply and turn the water supply back on. Consult your owner’s manual for more detailed instructions and diagrams.

Deciding Between the Dometic 310 and the Dometic 320 

Compare the Dometic 310 and the Dometic 320 side-by-side to help decide which toilet is best for your RV:

  Dometic 310 Dometic 320
Price Range $160-$210 (check here) $210-$270 (check here)
Additional Accessories (and price range) Upgraded seat: $35-$50
Hand sprayer: $30-$60
None – all included
Dimensions:   Maximum height (with seat up) Longest point (from wall) Distance from wall to flange center Max height: 33 inches
Longest Point: 19 inches
Wall – Flange: 10 inches
Max height: 35 inches
Longest Point: 22 inches
Wall – Flange: 11 inches

The Dometic 320 is clearly a better choice in nearly every category. The elongated seat and deeper bowl are a huge selling point, as well as the comfort of the seat.

In terms of flushing, the two models seem comparable, though the Dometic 310 has a slight advantage when considering user reviews and overall customer satisfaction. Since the 320 comes with a hand sprayer, this does a good job of compensating for any shortcomings in flushing effectiveness. 

The price difference between the two toilets is about $50-60, but these savings disappear quickly if you choose to add any additional upgrades or accessories, so arguably the Dometic 320 is also the better value for the money.

Despite all of the advantages, the size of the Dometic 320 was a deal-breaker for us. The bathroom on our rig was not designed for a larger toilet so we chose to keep the Dometic 310 that was already installed when we bought it. I have personally used the 310 daily for over 3 years and everything is still in good working order.

The cheap plastic seat is less than ideal and has plenty of cosmetic damage from ordinary wear-and-tear. My husband is uncomfortable using this toilet and chooses to walk to campground restrooms whenever possible. If we had the choice to upgrade our toilet to the Dometic 320, we would gladly do so.

Bottom Line Summary: If you are choosing between the Dometic 310 and the Dometic 320, the 320 is my recommended model, but measure carefully and be sure that it will work in your space. If it doesn’t fit, the 310 model is still a great choice.

If you enjoy outdoor travel and you don’t want to stay in a hotel, here is How to Find the Best Small Camping Trailers with Bathrooms and how to choose the right one for you!

FAQs About RV Toilets

How do you repair a Dometic RV toilet?

Whether or not you can repair your Dometic RV toilet depends on what is wrong with it. Seals and hoses are the parts that are most likely to wear out with time, which can cause leaks. The flush ball seal is another common part that can be replaced.

If the flush ball seal is not sealing well, it will no longer prevent odors from escaping the black tank. In other words, you’ll notice. Most of these parts are available from RV supply stores and you can do the work yourself or hire a repair technician. Consult the owner’s manual for your toilet for instructions, and use YouTube as a resource to see the work done before attempting a DIY repair.

What is the best RV toilet?

The best RV toilet for you is whichever toilet fits in your space and is the most comfortable for you. The Dometic 320 is an excellent choice for an RV toilet with similar comfort to a residential toilet, but its size makes it a poor choice for many RV bathrooms. If the Dometic 320 does not fit, the Dometic 310 is another quality choice that fits in most RVs. 

How do you remove a Dometic RV toilet? 

First, be sure to turn off the water supply. When the water supply is off, carefully remove and drain the water line to the toilet. Then loosen the bolts or screws that hold the toilet to the floor. You should be able to lift the toilet off the floor and carry it out at this point since it is no longer attached to anything. The old floor flange seal and bolts can be discarded. Your new toilet will come with a new floor flange seal and bolts that you can use when installing it.

Can you replace an RV toilet with a regular toilet?

Generally, you cannot replace an RV toilet with a regular residential toilet. RV toilets are specially designed with travel and movement in mind and residential toilets are not well-suited to these conditions.

The exception is if you have a travel trailer that is permanently stationary in a location with full access to sewer and water hookups. If your bathroom has space to accommodate a residential toilet, and you are certain the trailer will not be moved in the future, you can swap out your RV toilet. You will most likely need to remove your black tank and connect the toilet directly to the sewer connection. 

Further Reading:

Similar Posts