This camper could throw sewage out of the exhaust pipe

Sewage in a camper, caravan or motorhome These are the sewage waters. The ones that come out of the toilet in these recreational vehicles. They are stored in a tank full of chemicals that must be emptied. A very unpleasant task, one that requires luck.

But a specialist in camper accessories found the formula to dispose of them while driving: as convenient as pressing a button next to the steering wheel to release them through the exhaust pipe onto the roadYou read that right.

“Now you can evacuate your tank comfortably from the driver’s seat”

The system in question was called Thermasan, developed by Thetford. This firm continues to offer solutions for this type of vehicle, from the kitchen to the bathroomBut if you go to their sanitary section you won’t find this Thermasan anywhere.

It was launched in the 1960s and by the mid-1970s it was already in its third generation. It could be equipped with various recreational vehicles: for example, the 1970s GMC Motorhome, But before that, the Ford Condor Motorhome or Airstream caravans did so. At the end of the 70s it stopped being soldThere were several possible reasons, but first let’s look at the system itself.

Thermasan system advertising brochure

From the toilet to the road. The operation of the Thermasan was simple: emptying the sewage tank through the exhaust, burning it. Although some of this wonderful waste was also spilled onto the asphalt: approximately 20 liters per hour according to the GMC manual.

For this purpose, the sewage tank was connected to the exhaust manifold: this waste was blown in by a pump driven by a windshield wiper motor. A grid prevented solid waste from entering the exhaust, avoiding clogging it. For more details, here is the installation manual.

The system was operated from a control panel on the steering wheel: When the engine reached a sufficient temperature and was travelling at more than 50 km/h, a warning light came on and evacuation could be carried out. Or more specifically, when The exhaust gases exceeded nearly 480ºC. This is what allowed these residues to be disinfected, according to its creators.

In reality, however, the tank had to be emptied continuously, as not all of the contents were released to prevent it from drying out inside. But instead of emptying it every so often, Thetford indicated that doing so once or twice a year was sufficient.

Thermasan system advertising brochure

Why did it only last a decade on the market? We can think of many reasons why this technology is not present in camper vans and motorhomes today. The obvious one is that it is not necessary to go around dumping such unhygienic ballast on the road. But in reality there were other reasons.

On a GMC forum A user asked why Thermasan was no longer being fitted to recreational vehicles. The answer with the reasons was given by a former Thetford employee.

The first that Motorhome sales dropped significantly in the mid-70s due to the oil crisis. This led to the bankruptcy of many camper van companies: this was not the case with Thetford, but as Thermasan was an extra, it had a good chance of being marketed.

On the other hand, emissions regulations were beginning to be adopted at that time. And Thetford began to encounter obstacles to selling it in some US states because it meant modify and drill the exhaust systemThey also had problems with the hose that connected the tank to the exhaust, which degraded quickly due to high temperatures.

But another reason had to do with using the system itself. With the heat of the exhaust gases, the water evaporated, and cellulose and biological solids were also burned. Feces, that is. But not the urea or ammonia present in urine. “That means you’re left with a warm diaper smell.”says this former employee of the company.

Although it was not proven at the time that this bothered users, it is clear that no one likes such a stench to be present in the vehicle while living on board or simply driving.

The truth is that similar technologies have been attempted to be relaunched, but also without success. In 2011, A new interpretation of Thermasan was made which did not get the necessary investment. In addition, there is a portable toilet called Incinolet which burns waste instead of storing it in a tank. It can be installed on ships, trains or facilities without access to sewers. But of course, it doesn’t dump feces and urine in the process.