Thetford toilet seals

Mike Harding · Guru

Thetford toilet seals

Santa · Guru

G'Day Mike, I replaced the seals on my Thetford cassette a few months ago, easy job, I bought the parts from these people, they have a good range of Thetford spares and ship promptly. smile

https://www.caravansplus.com.au/bathroom/toilet-parts/

Bobdown · Guru

Hi Mike,

The seal is not designed to hold water while not in use, it will seal when the seat is sat on, then release the blade when finished, and leave empty.

A bit of olive oil or non petrol based lube is recommended a couple of times a year.

Bleach is a no no too, as not used in chemical toilets, use Thetford products for best results.

Cheers Bob

Possum3 · Guru

Agree with Bob regarding olive oil spray, but Nappy Soaker better for environment than products containing formaldehyde. Chronic or prolonged exposure to formaldehyde through inhaling can also cause severe side effects such as lesions in the lungs as well as laboured breathing which can lead to long term damage to the lungs.

Mike Harding · Guru

Thanks for you replies - I am pretty sure bleach was the culprit. Live and learn.

Bobdown wrote:
The seal is not designed to hold water while not in use, it will seal when the seat is sat on, then release the blade when finished, and leave empty.

That confuses me Bob; if the seal won't hold water when not compressed then it will allow gasses to escape from the holding tank which is not really what one wants. Also mine has been holding water most effectively for 11 months.

I use 35% sodium percarbonate nappysan as a break down agent and that works very effectively and may be poured into bush toilets which the Thetford products may not I believe.

Possum3 · Guru

Mike if I interpret Bob correctly he is saying he only puts water over the blade prior to using for No 2's. There are a lot of people that don't put any water over the blade as they believe when using for No 1's that miniscule amount of water is filling their cassette prematurely. Of course the units are designed to have water over seals at all times (odour control) - just remember to empty that miniscule amount of water and close the blade again prior to removing cassette for emptying.

-- Edited by Possum3 on Monday 7th of October 2019 05:05:51 PM

Santa · Guru

Mike Harding wrote:
I use 35% sodium percarbonate nappysan as a break down agent and that works very effectively and may be poured into bush toilets which the Thetford products may not I believe.

I also use sodium percarbonate (Nappisan) as well as a few drops of Eucalyptus oil for odour control, the original seals lasted 12 years, much cheaper and just as effective as the Thetford products. smile

Bobdown · Guru

Mike Harding wrote:
Thanks for you replies - I am pretty sure bleach was the culprit. Live and learn.
Bobdown wrote:
The seal is not designed to hold water while not in use, it will seal when the seat is sat on, then release the blade when finished, and leave empty.
That confuses me Bob; if the seal won't hold water when not compressed then it will allow gasses to escape from the holding tank which is not really what one wants. Also mine has been holding water most effectively for 11 months.
I use 35% sodium percarbonate nappysan as a break down agent and that works very effectively and may be poured into bush toilets which the Thetford products may not I believe.

The seal at the base of the bowl and top of the cassette will not hold any serious amount of water unless seated, otherwise you would not be able to remove the cassette easily, water will find its way down.

The blade on the cassette seals well, when carried it is on it's side and it doesn't leak, a little bit of water remains under the slide cover sometimes but the cassette doesn't leak or smell, you can't leave water in it like a 'P' trap to make a water seal for smells.

I like the Thetford bags you just drop in, no mixing or mess.

Still trying to show Jayne how to empty it, but she's a wake up to me.

cheers Bob

Tony Bev · Guru

I also brought a new seal from the same place as Santa, (Caravan Plus), I find them easy to deal with, and pay with PayPal

I found after I removed the old one, that a few granules from the Napisan/Boost were lodged in the seal, preventing the slide from holding water

I now use half a plastic milk bottle, (which fits in the lower cassette compartment, with Napisan/Boost), as a funnel, when adding the Napisan/Boost

Even after using bleach, some Olive Oil may soften the seal up, enough to hold water again

wendycarlene · Veteran Member

After about 10 years of falsely economising instead of using the Thetford products made for their things, I have proven that Thetford products work best. The cheaper Napisan equivalents work well, but the Thetford Green liquid is better, look for it on special and then stock up. There is now a pink spray to use after using the toilet not every time ,but say once a day, which keeps the seals in good condition, no need for eucalyptus and the like. Also there are fine paper things called Happy Bowl liners to use before bowel action, keeping bowl cleaner. Also ,some people only use toilet for urine, need to read instruction booklet. Thetford Toilet is made for both and works best if used that way. Much research has gone into this very convenient item for camping from the Portapotti to the bigger toilet.

SouthernComfort · Guru

wendycarlene wrote:
After about 10 years of falsely economising instead of using the Thetford products made for their things, I have proven that Thetford products work best. The cheaper Napisan equivalents work well, but the Thetford Green liquid is better, look for it on special and then stock up. There is now a pink spray to use after using the toilet not every time ,but say once a day, which keeps the seals in good condition, no need for eucalyptus and the like. Also there are fine paper things called Happy Bowl liners to use before bowel action, keeping bowl cleaner. Also ,some people only use toilet for urine, need to read instruction booklet. Thetford Toilet is made for both and works best if used that way. Much research has gone into this very convenient item for camping from the Portapotti to the bigger toilet.

We also tried the Napisan/Boost idea for a while. Have since returned to Thetford products which are more convenient to use and work better. I usually add a couple of bottles to our stock whenever Anaconda has a 30% off storewide sale. Never had a problem with seals.

Cupie · Guru

SouthernComfort wrote:
wendycarlene wrote:
After about 10 years of falsely economising instead of using the Thetford products made for their things, I have proven that Thetford products work best. The cheaper Napisan equivalents work well, but the Thetford Green liquid is better, look for it on special and then stock up. There is now a pink spray to use after using the toilet not every time ,but say once a day, which keeps the seals in good condition, no need for eucalyptus and the like. Also there are fine paper things called Happy Bowl liners to use before bowel action, keeping bowl cleaner. Also ,some people only use toilet for urine, need to read instruction booklet. Thetford Toilet is made for both and works best if used that way. Much research has gone into this very convenient item for camping from the Portapotti to the bigger toilet.
We also tried the Napisan/Boost idea for a while. Have since returned to Thetford products which are more convenient to use and work better. I usually add a couple of bottles to our stock whenever Anaconda has a 30% off storewide sale. Never had a problem with seals.

Me too.

Much prefer the Thetford products & the extra cost is nothing in the scheme of things.

I never buy anything from Anaconda unless it has at least a 30% discount.

ps .. A previous post if I read it correctly, seemed to suggest that some people put water over the flap/slide when using the toilet for a number 2. Perhaps I've been using it incorrectly for all these years. I just open the flap & 'thud' or 'plop'. Never use paper liners on the bowl either. Just position self correctly over the hole. Have I got it wrong?

pps. I too use olive oil spray on the bowl (to make it slippery) & the seal (to keep it pliable). I give both a good clean with 'Duck' or similar when emptying & re spray. All seals good after 20 years' use.

dieseltojo · Senior Member

Just some thing about seals on toilets of all description.

It is not a good idea to not use any oils directly or Vaseline etc. Some manufactures advise these things and as time goes bye with different models the components change to cheaper alternatives and you are the recipient of misinformation.

The more they make these things the cheaper they try to build them.

The only thing to use in the long run is an inert product like a teflon grease for seals provided from a bearing replacement supplier. That will solve any models problem over many years of changes to designs.

For example my toilet directions are straight out " Do not use olive oil on the seals" All they had to do was use neoprene seals but that would cost them 3 cents more per unit. smile

Mike Harding · Guru

Well the damn thing is sealing again now!

A pity really as I have just bought two replacements for $55. Oh well... at least I'll have spare toilet seals for the next ten years :)

Incidentally; when I pour the nappysan mix into the holding tank I do it via the emptying spout so it never touches the seal.

And for the people using Thetford breakdown products: they do an excellent job I have no doubt but *please* do not empty them into bush toilets as they will kill the bacteria which make such systems work - *only* empty into formal sewerage systems.