C4 Cassette® Toilet

Frequently Asked Questions

Cleaning and maintenance

What products should I use to winterize my RV sanitation system?

Clean toilet with Aqua Clean® or Aqua-Foam™. Add Toilet Seal Lubricant and antifreeze to the toilet bowl. Clean black and grey water tanks with Tank Blaster®. Add holding tank treatment, Drain Valve Lubricant, and antifreeze if freezing is possible, to each tank. Sanitize the fresh water tank with Fresh Water Tank Sanitizer.

What do enzymes do in my black tank?

Enzymes accelerate the natural breakdown of waste and toilet paper in the holding tank to reduce the malodors and prevent clogging during discharge.

Can I leave my dump valves open when I have sewer hookups at my camp site?

Never leave the black tank dump valve open during use even if you have a sewer hookup at your campsite. If left open during use, the liquids will quickly drain leaving a pyramid of solids in the tank directly below the toilet. The solids are a source of odors and can plug the toilet as well as the entire tank when trying to remove the build up. You can leave the grey water tank dump valve open with a sewer hookup.

However a good rinsing and cleaning with Tank Blaster® may needed overtime to remove any grease and solids built up in the tank.

Tank Blaster®

How do you use Level Gauge Cleaner?

To clean gauges, choose a warm day, above 75F, pour 1/2 of bottle of LGC into 40 gallon black holding tank through toilet opening. Pour 1/2 of bottle of LGC into 40 gallon grey holding tank through sink or shower drain. Flush the drain with running water and fill the tank. Mix by driving around and let it sit 24 hours. Drive vehicle again to loosen deposits. Empty and rinse holding tank. Product’s effectiveness doubles between 75 and 85 F. DO NOT use in freshwater tank.

Why do I need to use toilet treatments?

Toilet treatments are important for keeping holding tanks clean free from clogging. Treatments breakdown solids, clean the walls of the tank, and reduce malodors.

How does Aqua MAX® treat the waste in my holding tank?

The biological and enzyme ingredients in Aqua MAX® accelerate the natural breakdown of waste and toilet paper in the holding tanks to reduce the malodors. The fragrance in the product assists to mask any remaining odors.

How often do I have to replace the lip seal?

Thetford® recommends replacing the lip seal every four to six years, depending on how often the toilet is used. Some suggest treating the seal between the bowl and Cassette® at least twice a year.

What is causing the leak behind my toilet?

More than likely, the cause of the leak is a bad vacuum breaker and this would need to be replaced.

How do I clean my toilet?

Aqua Clean® is a multi-use cleaner for all surfaces including your toilet. A soft cloth or a sponge is recommended. Bristle brushes are discouraged as they may mar the surface of the toilet.

Troubleshooting

Where is the serial number located on my cassette toilet?

The serial number label can usually be found near the location where you remove the tank. There is also a serial number on both the cassette and the tank.

What can I do when the flush of my toilet doesn't work?

For models SC and CW, you need to troubleshoot the direct connection to the RV freshwater tank.

What should I do if I have a warranty claim?

For parts and/or service – including those under warranty – contact a local Thetford®/Norcold® Authorized Service Center (ASC) or an RV Dealer. Under the Warranty Program, Thetford®/Norcold® replaces or repairs toilets and/or parts, and pays the Authorized Dealer for warranty labor.

Warranty Information

How do I identify my toilet model if it doesn't have a data tag?

To help identify the Thetford® toilet, please send over some pictures of the unit and/or provide answers to the questions below:

Is the unit a hand flush, foot flush, or wall panel flush?

If a hand flush:

Is it a mechanical lever or an electric button?

If it is an electric button, does it have one button or two?

If a foot flush:

Does it have one or two pedals?

Locate the pedal(s) when sitting on the toilet (left side or center).

If a wall panel flush:

Does it have one or two buttons/switches?

*Please also include a picture of your wall panel?

Is the bowl porcelain or plastic?

How to

Should I travel with water in the flush tank?

It’s recommended not to travel with water in the flush tank to prevent water damage to the vehicle. For example, Thetford® advises against traveling with water in the flush tank of the C400 bench cassette toilet.

What is the weight limit capacity on my toilet?

All Thetford® toilets are tested up to 350 lbs. / 159 kg.

Where can I locate the serial number for my toilet?

Generally, there is a data tag on the back of the toilet (this can be a tight fit to get to) but can sometimes be on the base of the toilet, depending on the model.

RV Toilets Serial Number Identification

What's so different about my RV plumbing?

RV toilets use a small amount of water during flushing

• Only 1 qt of water is used for flushing, opposed to 1.6 gallons used by a home toilet

Holding tank holds waste for several days – it’s not a mini septic tank

Major challenges:

• Deodorizing the RV waste holding tank
• Keeping the holding tank clean
• Treating super-concentrated waste

Is a permanent toilet the same as a macerator toilet?

No, a permanent toilet is not the same as a macerator toilet. A permanent toilet uses gravity to evacuate waste into the holding tanks while a macerating toilet generally have a pump with a macerator that breaks down and pushes waste into the holding tanks.