Thetford Cassette Cleaning (Report Back)

[Bill Ord]

Last November I mentioned that I'd read a tip in a French magazine which recommended adding a small amount of dishwasher salt to the cassette every time chemical was added. The idea was supposed to prevent lime scale forming. Derek Uzzell asked if I'd report back on the success or otherwise of this idea. I've used this now for 140 nights away this year and have found it did entirely prevent limescale build up in the cassette. A £0.70p bottle of dishwasher salt from Tesco has lasted the entire time. I also found that sprinkling dishwasher salt onto the "blade" in the toilet and adding water and gently rubbing with the toilet brush easily removed limescale. I'm still going to do my usual annual cassette thorough clean but it will be very much easier as there is absolutely no scale in evidence. The only down side was having to carry an extra chemical.

 

Bill Ord

[Guest Tracker]

Nice one Bill - I too have a dislike of limescale so I'll do likewise - thanks for the tip.

 

I wonder why Thetford don't put salt in the loo blue?

 

Or is it because they wouldn't then sell any of their loo cassette cleaner!

[empress]

Very helpful, Bill. Will try it ourselves.

 

Empress

[Basil]

Hi all, sorry to be thick but what do you mean by 'dishwasher salt' as our dishwasher uses salt but that is just what it is, salt and is crystals in a plastic bag not liquid in a bottle! Ours also uses dishwasher liquid cleaner and dishwasher rinsing agent.

I can't see that putting salt onto the blade of the toilet would be very helpful or would it?

 

Bas

[Brian Kirby]

Excellent, Bill.  Do you know whether the blue, or green, Thetford stuff makes any difference?  Also, roughly how much did you add - teaspoon?

[Derek Uzzell]

Bas:

 

Dishwasher salt is a particular grade of crystalline sodium chloride intended for use in dishwashers. The salt is used for the same purpose as (and is very similar to) water softener salt, namely to regenerate ion-exchange resins used to remove the hardness-ions calcium and magnesium from water. Dishwasher salt is in a granular form, with particles larger than common table salt and unlike table salt has no added iodine (included as a dietary supplement). The granule size ensures that the salt dissolves slowly and that fine particles do not block the softener unit.

 

Table, cooking, rock and sea salts may contain additives that can actually increase water hardness. Also, the fine consistency of some of these salts mean they are likely to clog when wet. Granular dishwasher salt should always be employed because it is very pure and is the right consistency. Granular salt is the ONLY type of salt that should be used to regenerate a dishwasher water-oftener.

 

There is a need to be aware that some varieties of ‘dishwasher salt’ use Dead Sea salt. This variety may contain minute insoluble organic matter that may adversely affect the resin within the water softener over time. If you are in doubt about the origins of the salt, ask the retailer or manufacturer.

 

(All you needed to know about Dishwasher Salt courtesy of GOOGLE)

[kelly58]

Would it be advisable to add the salt to the flush water tank or would the salt effect the pump , we live in a real hard water area , but we have noticed when in France the water is a lot softer so the use of salt would be less one assumes

[Bill Ord]

Hi,

The amount of dishwasher salt CRYSTALS added to the cassette each time is about 1 tablespoon.

 

Bill Ord

[Basil]

Derek Uzzell - 2008-10-30 7:29 AM

 

Bas:

 

Dishwasher salt is a particular grade of crystalline sodium chloride intended for use in dishwashers. The salt is used for the same purpose as (and is very similar to) water softener salt, namely to regenerate ion-exchange resins used to remove the hardness-ions calcium and magnesium from water. Dishwasher salt is in a granular form, with particles larger than common table salt and unlike table salt has no added iodine (included as a dietary supplement). The granule size ensures that the salt dissolves slowly and that fine particles do not block the softener unit.

 

Table, cooking, rock and sea salts may contain additives that can actually increase water hardness. Also, the fine consistency of some of these salts mean they are likely to clog when wet. Granular dishwasher salt should always be employed because it is very pure and is the right consistency. Granular salt is the ONLY type of salt that should be used to regenerate a dishwasher water-oftener.

 

There is a need to be aware that some varieties of ‘dishwasher salt’ use Dead Sea salt. This variety may contain minute insoluble organic matter that may adversely affect the resin within the water softener over time. If you are in doubt about the origins of the salt, ask the retailer or manufacturer.

 

(All you needed to know about Dishwasher Salt courtesy of GOOGLE)

 

Thanks for that Derek, so would you dissolve the crystals first if you were to put it onto the blade of the toilet, I can see that leaving them to dissolve in the waste tank would be ok, but I was wondering if there could be damage done to the seal on the toilet blade if you put solid crystals on it hence my origional question as the first poster (sorry forgot who it was) was saying that he used Tesco dishwasher salt in a bottle so thought maybe it was a liquid?

I am being genuine here by the way and trying to understand, as I know Thetford are very critical about what you can and can't use on their products.

 

Bas

[J9withdogs]

Am I being thick?

 

How does salt added to the tank get to the limescale?

[Brian Kirby]

J9withdogs - 2008-10-31 5:49 PM Am I being thick? How does salt added to the tank get to the limescale?

Janine

It doesn't remove the limescale, it prevents its deposition - I suspect by maintaining the free lime content of the urine in suspension, so that it is simply disposed of with the tank contents.

[Derek Uzzell]

Bas:

 

To quote Bill Ord:-

 

"I also found that sprinkling dishwasher salt onto the "blade" in the toilet and adding water and gently rubbing with the toilet brush easily removed limescale."

 

As Bill is evidently dissolving the solid grains of salt on the blade before the toilet is returned to use no harm should result. However, I'd be a mite wary of using this method with older models of Thetford toilet where the blade simply slides sideways, as was the case with the C2 bench model on our 1996 Herald. With this type of blade action, if any salt grains remain un-dissolved on the blade, or become trapped between blade and seal, there's the (small) possibility that the seal might be abraded. The blade on our present C-200S swivel-bowl toilet has a 'dual action', opening/closing vertically before/after moving sideways, so, even if granular salt remained on the blade or seal, it would be much less likely to cause damage. I don't recall having scale form on the blade of either of our motorhomes' toilets. This may because our motorcaravanning trips tend to be of relatively short duration and/or the way our toilets have been used.

 

Whether putting dishwasher salt into a toilet's flush-tank (assuming it's got one) is a wise plan would need to be proved in practice. Me, I'd wonder about the possibility of the salt 'sludging' within the tank and clogging up the water-feed from tank to toilet-bowl. Might be worth asking Thetford's advice, though I expect they'd recommend just using their Pinky-Rinsy stuff.

 

Having a SOG system on our motorhome, we don't use any toilet chemicals. I haven't found scale build-up within the cassette to be excessive and I find cleaning the cassette annually with a citric-acid solution is sufficient.

 

In the past I've said that I've never found the waste being emptied from our 'no chemicals' cassette especially objectionable pong-wise - something Mel Eastburn has occasionally highlighted regarding SOG systems. I now realise that my view had been coloured by our rare use of campsites meaning that the cassette emptying process had normally been out of doors. On a French campsite visited recently the chemical-toilet emptying point was within the toilet block in a small enclosed cubicle and - wow! - I rapidly understood why peoples' noses might be offended by the acrid odour. While this revelation won't encourage me to use toilet chemicals, I shall in future be particularly careful to empty the cassette downwind of other campers.