Product Review: Dometic 970 Series Portable Toilet

There’s a television commercial that still plays occasionally in which a very honest-looking woman says “It’s time to get real about what goes on in the bathroom.” I like it because it’s probably the most truthful line in advertising to hit mass media in a decade.

You can ask Mrs. $tingy. Discussions around what goes on in the bathroom are near the bottom of my list of topics to discuss in polite company. Or rude company for that matter. I find them all to be pretty juvenile and worthless. But I’m usually a pretty serious guy, so there you go.

Before I go any farther, a bit of legal housekeeping. This post contains affiliate links. That means I receive a small commission if you make a purchase using these links. Those commissions help to pay for the costs associated with running this site so that it stays free for you to enjoy. For a complete explanation of why I’m telling you this and how you can support this blog without paying more, please read my full disclosure.

Upgrade your toilet tech

So for me to write a review about a portable toilet, there has to be a good reason. The reason is that I was fed up with replacing the portable toilets on Summer Dance and I found a better product. I’ve shared this with enough other skippers going through the same thing that I want to write about it here to hopefully save some of you that frustration as well.

Summer Dance came to us with a classic, bellows-style portable toilet. The only good thing about it was that it had a 5 gallon capacity. Not that we needed that much capacity, but because the base of the toilet was bigger than most and fairly stable since it wasn’t attached to the cabin floor. It sat between four teak cleats screwed to the cabin floor. If it had a smaller footprint, it would be easy to tip over, especially before it’s been used much. That’s when most of the water is in the upper tank and makes it top-heavy. The bellows on that toilet started leaking by the end of our first season with it.

First bellows failure

The classic style portable toilets work by you pumping the bellows by hand, which shoots clean water from the upper tank around the bowl and down into the bottom tank when you open the valve to flush. The biggest problem with these is that the soft plastic bellows dry out with age and crack so that they don’t wash the bowl anymore, not a pleasant prospect. The cost of replacement bellows is ludicrous, $30-40. There’s simply no good reason for that part being that expensive. Planned obsolescence is what it is, combined with price gouging if you ask me.

I replaced that first portable toilet with a similar type from a respected brand – a SeaLand SaniPottie 960 to be precise. The SeaLand brand is now owned by Dometic. I expected it to last long enough to earn its reputation. Oh, no. The bellows on the second toilet didn’t last the next season before it gave out.

The second bellows failure

Fool me once, shame on you. Fool me twice, shame on me.

There’s no shame in having a push-button pottie

I was not going to buy a third toilet with the same design and invite even more shame. So I did a little research and found a portable toilet that uses a different flushing mechanism. Instead of a bellows to pump the clean water into the bowl, the Dometic 970 series toilets use a tried-and-true piston style pump to pressurize the clean water tank with air. It’s the same principle as your pressurized alcohol stove. Then all you do is push a button to discharge water into the bowl.

Pump, then press

Depending on how long you press the button, more or less water discharges, so you can get multiple flushes from one charging. The result is a more reliable mechanism and a more forceful flush. That was all the proof I needed but the real test was up to the first mate who uses it most.

I purchased a 5 gallon capacity Dometic 975 last year and both the first mate and I have been happy with the choice. It sits taller than the 2.5 gallon toilets, which is more comfortable in the little head compartment of the C-22 and it just fits under the V berth boards.

The 974 and 975 models include floor mounting brackets so you don’t have to worry about the toilet sliding around or tipping over. You can remove the entire toilet easily by pulling out a large, sliding tab in the lower tank that engages the front bracket. The rear brackets engage with slots in the rear of the lower tank. This design also lets you remove just the upper tank while leaving the lower tank fastened to the brackets, something you cannot do with most other toilets.

The metal Dometic mounting brackets surrounded by the original teak cleats

The toilet I purchased also included a Marine Sanitary Device (MSD) fitting kit, coincidentally. It replaces the pour spout so that you can plumb the lower tank up to the deck for dockside pump outs. I don’t plan on doing that but it’s nice to have the option for the future.

The Dometic 970 series toilets are like other portable toilets in most other respects, which is fine. The two tanks separate easily for loading and dumping. There’s even a convenient sight window in the lower tank so you can easily see the fluid level before it gets too full.

A swiveling spout and a vent knob on the lower tank help with splash-less emptying

Material quality, construction, and finish are excellent. The plastic is thick and glossy, making the Dometic look more like a proper marine head than an ice chest for a hobbit. There are no metal parts to rust or corrode. After a year of use, the toilet has had no problems and still looks new.

There are four models in the 970 series. To help you choose the one that’s right for you, I’ve summarized the differences between the models in the following table. All models come with either a gray or tan bottom tank.

Model Capacity Brackets
972 2.6 g. Optional
974 2.6 g. Included
975 5.0 g. Included
976 5.0 g. Optional

An MSD fitting kit for the 5 gallon toilets is available separately.

If you’re in the market for a portable toilet, I can confidently recommend the Dometic 70 series toilets and has some of the lowest prices.


Would you like to be notified when I publish more posts like this? Enter your email address below to follow this blog and receive notifications of new posts by email. You will also receive occasional newsletters with exclusive info and deals only for followers and the password to the Downloads page. It’s free and you can unsubscribe at any time but almost nobody does!

Enter your email address to subscribe to this blog and receive notifications of new posts by email.


16 Comments Add yours

  1. Tom Luque says:

    There are certain liquid & crystal chemicals you can add to bottom tank for certain benifits I don’t wish to remember.
    This past season I replaced the pump potty with the 5 gallon bucket toilet seat with chemical bag. Because my multi day trips are well planed, my crew and I have not had to deploy it yet. Untill then, the bucket is good for storage, washing feet or hauling water up for a wash down.

    1. That’s a good plan. Put the container to other use until it’s needed for latrine duty. I’d be okay with that but the first mate wouldn’t set foot on the boat without better “facilities.” I love her so happy wife, happy life.

  2. John McGuire says:

    I looked at some youtube reviews for the Thetford Curve Porta-Potti also. It has a battery powered pump, not a big deal except that I read some reviews where people didn’t like the wanky sound of the hand pump on the Dometic 970 series. What I liked about the Thetford is a much higher seat and a built in paper dispenser.

    1. That Thetford is nice but it’s too tall to fit under the V berth if you plan to sleep there. Plus, headroom there is scant at best so unless you’re under average height, you might find it is an even less comfortable sitting position.

  3. Rich Weston says:

    I have the old porta potti with the bellows and have had the same issues with it as you. Plus I don’t really like the mounting system they include. You have to lift latches on the side of the toilet to lock it down and release it and the porta potti space in my Precision 21 doesn’t have enough room on the side to allow you to lift the latches.
    I definitely want to get the Dometic but am not sure if I should get the 2.5 gallon or the 5 gallon. I’m pretty tall and I’m afraid the raised height may make the 5 gallon too high.

    1. Maybe you could test the heights of each with a stack of books or something. For me, it’s easier to duck a little than it is to get down into and up out of a low squat in a confined space.

  4. I learned quickly while out for a couple of weeks, to pee in a 1/2 gallon milk jug, and forget the bellows or pump. When you need water to flush, just pore in the pee. Saves on fresh water too. I guess it wouldn’t work for the ladies though. Maybe a big funnel from the dollar store…oh well.

  5. a says:

    So the real question: does it smell? I’d love to get rid of our head (conventional) under the V-berth.

    1. Not any worse than other portable toilets that I’ve had. I keep it clean, use deordorants in the collection tank, and keep the collection tank vent closed except when emptying. Mrs. $tingy can out-sniff a bloodhound and she doesn’t complain if I do those things.

  6. Roger Hayman says:

    I have a Dometic 976. I am an average size 67 year old Caucasian male and I find the hole in the seat too small longitudinally to get my “tackle” in and cover my rear “exhaust” port at the same time. You have to evacuate your tanks one at a time, serially.

    In short, the seat hole is not big enough for adult males even though I think I have seen it advertised as adult-sized.

    This a shame because the small seat size is dictated by the tapering of the sides of the top unit starting from above the bottom (please excuse the pun) storage unit. If the sides did not taper, I think a larger seat would be possible.

    Also, on mine, the flushing jets fire down the sides and front but not down the rear (sorry, again) of the bowl. I don’t know if this is normal.

    I would be very interested to hear if other users experience the same issues.

    1. Your experience with the flush is about the same as mine, Roger. It’s not a forceful flush like we’re used to with our home toilets. It’s more of a gentle rinse but it’s stronger than the old bellows style toilet it replaced. I find that it sometimes takes multiple flushes to clean the bowl completely.

  7. I had a Thetford Curve porta-potti. I don’t like their mounting system. I’m very much concerned about odor and stability of a portable toilet. I definitely want the Dometic. Does it smell?

    1. Hi, Saisha

      The Dometic doesn’t smell any worse than other portable toilets that I’ve had. Keep it clean, use deodorants in the collection tank, and keep the collection tank vent closed except when emptying and you shouldn’t notice it.

  8. Greg Reddick says:

    What screws did you use to fasten it to the floor? I think that the screws that came with it are too long.

    1. I don’t recall, Greg. Either the ones that came with it or shorter ones, but I doubt it. I had no trouble installing the brackets.

  9. Donna says:

    I have a Dometic porta potty 975. The handle that keeps the seal from top to bottom has come out. I can’t get back into grooves to close it. Help!

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.