What To Do If Thetford Toilet Does Not Hold Water And Always Has Bad Odor?
Updated 09/25/2025 | Published 09/15/2025
Products Featured in This Question
Question:
i have a 2003 cascade. toilet thetford 20920. Not holding water in holding tank so always has bad odor?
asked by: Betty S
Expert Reply:
Hello Betty, thanks for reaching out. It sounds like your flush ball seal is bad. They can warp or crack which causes water to leak and lets bad smells out. We may have the seal you need, but I was not able to find any good references to the part number you provided. Even the Thetford site didn't show anything. The flush ball seals are largely model specific.
For example, the Replacement Waste Ball Seal # TH34FR33AB is for the Thetford AquaMagic Style II toilet like part # TH35SE. So if this is what you have, replacing the flush ball seal should resolve the issue.
Product Page this Question was Asked From
Replacement Waste Ball Seal for Thetford AquaMagic Style II Toilet
- Accessories and Parts
- RV Toilets
- Seals and Gaskets
- Flush Ball Seal
- Thetford
more information >
Featured Help Information
Instructions
Continue Researching
- Search Results: accessories and parts
- Search Results: rv toilets accessories and parts
- Q&A: Looking for Replacement Water Valve and Ball Gasket for Thetford 42058 Aqua-Magic Style II RV toilet
- Search Results: trailer leaf springs
- Search Results: spring
- Shop: Replacement Waste Ball Seal for Thetford AquaMagic Style II Toilet
- Search Results: hitch alignment
- Search Results: hitch guide
- Shop: Replacement Waste Ball Drive Arm Kit for Thetford Aqua-Matic Style II RV Toilets
- Search Results: morryde safe~t~rail telescoping rv hand rail
- Shop: Thetford Aqua-Kem RV Holding Tank Toss-In Pouches - Qty 16
- Shop: Replacement Flush Ball Seal for Dometic RV Toilet
- Shop: Rhino Premium Enzyme RV Septic System Liquid Treatment - Pine Scent - 4 Oz Singles - Qty 8
- Shop: Pure Power Blue Treatment for RV Holding Tanks - Fresh Clean Scent - Drop In Pouches - Qty 12
- Shop: Thetford Tank Blaster RV Holding Tank Cleaner - Black Water and Gray Water Tanks - Qty 4
- Video: Breaking Down the Thetford Aqua-Magic Style Plus RV Toilet
- Q&A: Is the Flange Seal in Thetford Repair Kit TH94MA the Same as TH43RA?
- Video: Review of Thetford Replacement Waste Ball Seal AquaMagic Style II Toilet - TH34FR33AB
- Q&A: Looking for Replacement Flange Seal for Thetford Aqua Magic Style II RV Toilet
- Video: Feature Breakdown: Replacement Hehr-Style Window Latch for Double Pane Windows
- Video: Review of Thetford Replacement Water Valve Aqua Magic Style II Toilet - TH78SA
- Q&A: How Long Does It Take To Install An Air Lift Air Bag Kit
- Q&A: Option For Replacing A 3313195.000 Thermostat In A 2017 Keystone Bullet Premier RV
- Video: Alpha Systems Patch Kit for SuperFlex RV Roof Membranes Feature Review
- Q&A: Replacement Flush Valve for a Thetford 42072 Toilet
- Q&A: Will the Replacement Water Valve for Thetford Aqua-Magic Style II RV Toilet Work w/ a Thetford 42070
Betty S.
9/25/2025
Not sure if I asked the question correctly. I don't think it's the actual above the floor toilet portion that is leaking. When I do a pump out, I add 5 bowl full of water to the holding take to avoid odor (parts per million). That water does not stay there and seeps out therefore each time the toilet is used it is waste only with no water and thus bad odor. The last time I did a pump out, the end of a plastic coat hanger came out and that's when the problem started. What is the bladder seal? Do you think that is something that would solve my problem.