One of the most convenient things about our pop up camper is our cassette toilet. I never imagined we would use it as frequently as we do. In fact, when we were shopping for campers, I didn’t even have a potty on our “must haves” list. Late night bathroom trips in bear country quickly changed my mind, though, and we are so glad we have this little convenience in the trailer.
We have a Thetford C4 Cassette Potti in our pop up camper. When we first brought our Santa Fe home, though, I couldn’t find much information on pop up camper cassette toilets at all. Our user’s manual had been destroyed by the previous owners, so we had to figure out how to use and care for our potty all on our own. It’s not all that hard, really. Let me show you what we’ve learned…
Preparing Your Pop Up Camper Toilet for Use
The actual operation of your cassette toilet is pretty easy. Under the toilet itself, you’ll find the holding tank. This is essentially your “black water” tank. We have an access door to the tank inside the camper, but many models have access doors located on the outside of the camper. Either way, when you open the access door, this is what you will most likely find. The first thing you’ll need to do is fill the flush tank. To fill the flush tank, rotate the fresh water fill spout 90 degrees away from the tank and remove the yellow cap.
As you fill the fresh water tank with clean water, pay close attention to the glass vial on the side of the tank. That’s the fresh water level indicator. When the water is about 1/2″ from the top, your tank is full. You can also use an additive in the flush tank, but we never have. We’ve done just fine filling the fresh water tank with clean city water. Once you are finished filling the tank, you’ll need to drain the remaining water from the fill spout. If you have a drain nozzle on the side of the fill spout, unscrew it and let the water drain into a cup. If you have no drain nozzle, your fill spout may be designed to rotate. If that is the case, rotate your fill spout and pour out the excess water. You can then screw the yellow cap back on your fill spout and return it to the original position.
Now you need to add chemicals to the holding tank of your cassette toilet. This will take care of any unpleasant odors in the the tank. 😛 We like to use liquid Aqua-Kem because it is relatively cheap and readily available. You can find it at Amazon, Walmart, or Camping World. Thetford recommends removing your holding tank by pressing down on the safety catch and sliding the tank outward. (Make sure that the valve blade–the rubber flapper inside the bowl–is closed when you do this.) Set the tank upright, rotate the emptying spout upwards, and remove the yellow cap. The yellow cap conveniently has a measuring cup built in, so you can accurately measure the amount of Aqua-Kem to add to the tank. We usually add about 4 oz. of Aqua-Kem and 2 liters of water to the holding tank. You’ll want to make sure the bottom of the tank is covered.
Replace the yellow cap and return the emptying spout to its original position. Now you can slide the tank back into place. Listen for the safety catch to “click” so you know the tank is locked into position. It’s a bit of a pain, but Thetford discourages adding chemicals through the toilet bowl, as it can damage the valve blade and seal. The Aqua-Kem instructions actually recommend adding chemicals through an open valve blade. Go figure??? We’ve always erred on the side of caution and added Aqua-Kem to the tank through the emptying spout. We figure it’s better to be safe than sorry. Thetford does make convenient toss-in packs of Aqua-Kem that you can add to the tank via the bowl. They are much more expensive, but would have been so much easier on our long trip. I may just have to grab a pack or two in the future. 😉
Using Your Pop Up Camper Toilet
From the outside, this is what our cassette toilet looks like. There is a valve blade inside the bowl, which when opened, empties the contents of the bowl into the holding tank below. To use the pop up camper toilet, turn the flush knob several times to fill the bowl with water or open the valve blade, which ever you prefer.
At this point, your toilet is ready for use. As a side note, we use a toilet paper designed for RV use, like this one from Scott. It’s available on Amazon and at Walmart. It is a little pricey, but we found it the cheapest RV tissue available. It’s not completely necessary to use RV toilet tissue, but it does break down quickly, making the task of emptying the tank a little easier. Once you’ve done your business, you can open the valve blade (if it wasn’t already open) and flush the bowl a few times with water by turning the flush knob. Close the valve blade after use. That’s it! Keep an eye on your tank level indicator throughout your trip. Once it turns red, it’s time to empty the tank. 😛
Emptying the Cassette Toilet Waste Tank
You should empty the waste tank on your pop up camper toilet as soon as the level indicator turns red. In fact, Thetford actually recommends emptying the tank before it is completely full. If the waste tank is too full, it will be more difficult to empty, so we usually empty our tank when it is about half full. Thetford cassette toilets were designed to be easy enough to empty in a bathroom toilet, but we haven’t done that yet. We usually use the campground dump station or the sewer clean-out at home. Check your campground rules for specific waste dumping regulations before you tote that tank into the public restroom. 😉 Here’s how to empty your waste tank.
- Make sure the valve blade is closed, and push the yellow safety catch down. Grasp the tank by the handle and pull it outwards.
- Rotate the emptying spout 90 degrees and remove the yellow cap.
- Hold the waste tank by the upper handle with one hand. Grasp the back of the tank with the other hand, making sure you can depress the vent plunger easily. This will allow you to empty the tank without splashing.
- Empty the tank into the appropriate waste receptacle by tilting the tank forward while depressing the vent plunger. Then thoroughly rinse the tank and valve blade with fresh water several times.
To thoroughly clean our waste tank, we remove the emptying spout by rotating it 180 degrees from the original position. It will then slide up and off the tank, allowing us to get the spout and tank really clean. We usually use about a quarter of a cap of Woolite and lots of fresh water. Then we replace everything and return the tank to its place under the cassette toilet. If we will be using the toilet again, we refill the deodorizing chemicals. If we are storing the camper, we open the valve blade to let the holding tank dry out well.
Cleaning & Maintaining Your Pop Up Camper Toilet
Cleaning your pop up camper toilet is actually pretty simple. You’ll want to steer clear of harsh or abrasive cleaners, as they can damage the bowl, valve blade, and seal. We usually use a little Dawn dish soap, a sponge, and water, but recently, I discovered a Thetford cleaner I really like. It’s called Aqua-Clean, and it is designed for cleaning RV kitchens and baths. It is safe for toilet seals, which was what I was most concerned about. I had a little trouble finding it. There wasn’t a cost effective solution on Amazon, so I had to drive to Camping World to pick up a bottle. It cost me about $10, but it will last for a long time. I really like that it does double duty, so I can use it for a general all-purpose cleaner in the pop up camper. I just spray down the outside of the toilet and wipe it clean with a wet rag. We use a lot of Thetford products, but I feel pretty comfortable that Thetford products were designed to work well with my Thetford toilet. There may be some other great brands out there, so if you use something different, please feel free to share in the comments. 🙂
To ensure your valve blade lives a long life, you’ll need to give it some love, too. The valve blade is like a rubber flapper, and can be damaged if not properly cared for. Once your valve blade and seal are damaged, they may leak or stick. To prevent that from happening, we use a toilet seal lubricant and conditioner from Thetford. We love this stuff. When we first got the camper, the valve blade stuck when we’d try to open it. After several applications of Toilet Seal, it now works perfectly. We use this stuff a couple times a year to keep everything running smoothly. We buy it on Amazon, but I’ve seen it at Camping World, too. If you can’t locate Toilet Seal, you can also use pure olive oil to lubricate and condition your seals. Never use Vaseline or vegetable oil, though, as these may cause leakage.
Thetford recommends that you empty your fresh water and holding tanks before traveling to reduce the risk of leaking or flooding. I’ll be honest, we’ve traveled a couple of times with water in the tank and had no issues, but it’s always better to be safe than sorry.
So that about sums it up! I hope you’ve learned a few things, and if you’re already a porta-potti pro, feel free to share your advice with us in the comments section.
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