How can I prevent a Scaled Toilet

Here is a suggestion from a few years ago (on this forum):

"Someone here recommended putting urinal tabs or cistern blocks in the inlet system. I fitted a jasco strainer, pulled out the gauze and stuck in a blue tablet for a cistern. Loo hasn't smelt since and it has cleaned out the lime scale. Highly recommended."

I haven't tried it personally, but it is on my jobs list.

I suspect you'll be wasting your time.
 
I would be deeply suspicious about bacterial contamination if a fresh water tank was plumbed into a typical Jabsco-type marine toilet inlet. However there are (expensive) marine toilets designed to run with freshwater: eg some vacuum toilets that also use very little water compared to traditional pump types.
Likewise I would not be comfortable drawing from the main water tank. Ok when first installed but it doesn't take much scale etc to create q route back to the tank. The ones I have seen use y diverter valves to switch between sea water and fresh water.
I generally use a fresh water flush. Not plumbed in but just pull out the shower head from sink.
 
I've worked on the principal that you cannot flush too much, 20+ at least, it is not as if the water you flush is expensive. Good work out too.

Good principle, but remember that some of us have boats with holding tanks, which fill up quickly if you flush copiously.
 
Um. Is that right? That's a worry that you mention this, given your pedigree as an advisor. In a failure scenario, what would be dangerous in particular? Obviously you don't want sewage in the water tank but I can't see how that would happen, but I don't know.

My current and previous boats both have FW flush and use the domestic water tanks for the supply. And just about every mobo built today over about 35' ish will have FW flush from the domestic tank. So maybe the tech has moved on?
My motorhome has fresh water flush from the domestic tank but there is no pumpout as with a boat. I think my jabsco electric toilet would be similar as the flush and pumpout are completely separate. A jabsco manual toilet would be a very different matter, with flush and pumpout on a single pump.
 
A lot of people recommend using vinegar, or some stronger acid, to remove scale but I assume it has to remain in contact with the scale for some time (hours?) before it breaks it down.

Just flushing the chemical through the lavatory means the chemical is only in contact with the scale for a moment before it is washed away.

How do people fill the discharge pipe with chemical and keep it in there for as long as needed?

The only way I can think of is to disconnect one end of the pipe, raise it above the other end and pour in the chemical.

Given the difficulty that is often encountered removing stiff old plastic pipe, and getting it to seal well on replacement, I think I would just fir a new length of pipe and save myself a lot of bother.
 
Urinals flushing regularly with fresh water, having those blocks in them or getting drain cleaner (trade strength) poured down them does jack (makes a fair bit of toxic smoke though) The only solution is to remove the pvc piping, beating it to dislodge the build up and replacing... It is quite incredible how quickly urinals become blocked on land based toilets !
So how do you prevent a scaled up toilet ? Not sure you can without using nasty chemicals that are not really fair on the marine life..and what will thoise nasty chemicals do to your khazi?
 
We had a blocked urinal in our surgery. The plumber who came to clear it told us that those deodorant blocks were a plumber’s best friend, He said they were the main reason for blocked urinals. He advised us never to use them again.
 
My motorhome has fresh water flush from the domestic tank but there is no pumpout as with a boat. I think my jabsco electric toilet would be similar as the flush and pumpout are completely separate. A jabsco manual toilet would be a very different matter, with flush and pumpout on a single pump.
Vyv, thanks. Now I get it. Yes my boat WCs are electric with fw flush supplied by a flush pump and the waste extracted to a tank, by a macerator and discharge pump. Never the twain shall meet...
 
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I agree with fresh water flush and plenty of it.
We do have rim block and that does seem to help.
Elsan blue kills odours when they do arise - but is nasty stuff. I intend to change to Ordourlos when the Elsan is consumed. But that is probably no help with scale - keep flushing.
 
A lot of people recommend using vinegar, or some stronger acid, to remove scale but I assume it has to remain in contact with the scale for some time (hours?) before it breaks it down.

Just flushing the chemical through the lavatory means the chemical is only in contact with the scale for a moment before it is washed away.

How do people fill the discharge pipe with chemical and keep it in there for as long as needed?

The only way I can think of is to disconnect one end of the pipe, raise it above the other end and pour in the chemical.

Given the difficulty that is often encountered removing stiff old plastic pipe, and getting it to seal well on replacement, I think I would just fir a new length of pipe and save myself a lot of bother.

I always fill our Raritan bowl with half a 5 litre container of ebay white vinegar on leaving the boat for more than a week, so about 2.5 Litres. This is pumped until the vinegar is right at the bottom of the bowl. By turning off the outlet seacock at this point I am fairly sure I have neat white vinegar in all or most of the outlet pipework, from the bowl to the seacock.

Upon returning to the boat and if in clear water I have had someone open the seacock and pump vigorously, after filling the bowl with fresh water first. A fine whitish cloud can be seen from near the outlet pipe if the current is from Port to Starboard at the point on the boat where the toilet outlet is situated. No current, nothing seen. I believe this cloud is the build up from the pipe, softened and discharged with the flushing. How much IS actually removed, cannot, of course, be measured.

Fairly subjective, but absolutely no doubt in my mind that white vinegar softens the build up in the pipe. It certainly keeps the bowl sparkling clean.

We are fortunate our boat had had very little use when we purchased her and the last two years were in fresh water. The holding tank has never been used so far - saving that for the future.

White vinegar is far from being a powerful acid, but regular use appears to work for us. I fitted a new Raritan overhaul kit to the pump two seasons ago and the pump and valves had little build up. The lead weight had become unattatched from the flap valve, the replacement is a moulded in rubber one.

I hope this helps.
 
I always fill our Raritan bowl with half a 5 litre container of ebay white vinegar on leaving the boat for more than a week, so about 2.5 Litres. This is pumped until the vinegar is right at the bottom of the bowl. By turning off the outlet seacock at this point I am fairly sure I have neat white vinegar in all or most of the outlet pipework, from the bowl to the seacock.

Upon returning to the boat and if in clear water I have had someone open the seacock and pump vigorously, after filling the bowl with fresh water first. A fine whitish cloud can be seen from near the outlet pipe if the current is from Port to Starboard at the point on the boat where the toilet outlet is situated. No current, nothing seen. I believe this cloud is the build up from the pipe, softened and discharged with the flushing. How much IS actually removed, cannot, of course, be measured.

Fairly subjective, but absolutely no doubt in my mind that white vinegar softens the build up in the pipe. It certainly keeps the bowl sparkling clean.

We are fortunate our boat had had very little use when we purchased her and the last two years were in fresh water. The holding tank has never been used so far - saving that for the future.

White vinegar is far from being a powerful acid, but regular use appears to work for us. I fitted a new Raritan overhaul kit to the pump two seasons ago and the pump and valves had little build up. The lead weight had become unattatched from the flap valve, the replacement is a moulded in rubber one.

I hope this helps.
Thanks I'll try that.
 
I’ve been doing this for maybe 5 years now and no scale, no smells, no problems. Do the business. Fill enough, say a third full to flush away, once clear, fill the bowl 2/3 full then flush away. That’s with a salt water flush. When leaving the boat. Fill the bowl with fresh, flush to empty, then leave. I’ve never needed vinegar or acid.
 
Hi all. Thanks for all your tips. I did a test today on 4 descalers/cleaners.
Unfortunately because of the lockdown I could not get hold of normal descaler (Sulfamic Acid I think) but I did try Sodium Hydroxide, Sodium Hypochlorite, Sprit Vinegar and Cider Vinegar. I have made a video of the tests if anyone is interested


The most potent and effective of them all was Sodium Hypochlorite which reduced the deposits to a foam paste. It is used in domestos and is an approved toilet cleaner so I would imagine that it would be safe for the toilet and pipe innards. My main concern is that the bottle had a warning to fish and wildlife on it and I need to look further into this to see just how potent it is.
I think the main lesson I have learnt from your comments is that we need to flush more. I looked at the Jabsco electric pump conversion but at nearly £400 I think that we shall keep pumping.
Other than that we shall do as the French and pee over the side.
 
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For many years Ive used a chemical cleaner, as mentioned before, Agua fuerte. Strong water. Hydrochloric acid at 26% solution. Its less than a euro a litre in most places in Spain.

On my liveaboard boat and commercial yachts Ive owned or operated, problem gone. No more taking blocked pipes off and cleaning/replacing.

Yay.
 
For many years Ive used a chemical cleaner, as mentioned before, Agua fuerte. Strong water. Hydrochloric acid at 26% solution. Its less than a euro a litre in most places in Spain.
On my liveaboard boat and commercial yachts Ive owned or operated, problem gone. No more taking blocked pipes off and cleaning/replacing.
Yay.

Only problem though, muriatic/hydrochloric acid can dissolve the tin in bronze skin fittings o_O
 
I am in the HCL (brick cleaner etc) camp. Once a season fill the bowl with a 50% solution of brick cleaner leave it to fizz then pump through. I find a 5l bottle of this stuff will totally clear the pipes - fill the bowl and repeat until its all gone. Remeber to let it stand to give it time to work. The same solution is ace for cleaning bronze props - just put them in and within a couple of minutes all the scale is gone and a mirror finish returns. Just be careful with splashes etc as it is acid

I have thought about re- using the black water tank ,which I only use rarely, as a source of fresh water solely for the head. If perchance it runs out I can re fill with sea water and there would be no chance of contamination
 
I posted this before . Be careful using HCL in your heads.

This is what happened to my Henderson MkV when I used HCL in my Lavac.

35917583272_b3c9b2cdd5_b.jpg


The HCL loosened the partially blocked outlet hose and a piece broke off and totally blocked the pipe which caused a buildup of pressure against the pump inlet valve blowing the pum apart.

This was the blockage in the pipe partial on the left and the piece blocking the whole pipe on the right.

36046505646_d8faa1ab2b_b.jpg


I replaced the yellow pipe with the white hose old for heads and the build up seem less but I also fitted an electric diaphragm pump with a timer which can be set to operate for the time needed to fully clear the outlet pipe.
 
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