BLOCKED HEADS PIPE!

phatcat1

phatcat1

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On Cento, our 2004 L36 we had a bit of a problem with our heads pipe over the new year holiday!.

We have always been very careful (read "paranoid") about what goes down our heads since we have had her.

Over the holiday period when aboard, the heads "blocked" one morning, absolutey solid, so I duely take the Jabsco apart to find no probs with that! That means the 2 way diverter in the aft transom locker must be the next suspect, so after half an hour of resting on my head and having to remove the diverter to get the pipe off, pumping the Jabsco reaveals the blockage must be in the 5 metre pipe that runs from heads, under shower tray, under aft bunk, ond out of transom! We try blowing pressure up pipe but nothing!

Only 1 course of action - replace pipe! So last Saturday, Neil from Yuletide and myself (thanks Neil) set about replacing pipe! Not an easy job (if you excuse the pun!) and anybody wanting to do it without removing the heads and shower tray should contact us and we will go through the process!

However, when old pipe was removed, it was solid with calcium/salt deposits for its entire 5 metre length, and it felt like concrete! The inner bore, instead of being 1.5 inches, was less that 0.5 of an inch, and some of this "shale" had broken and blocked the pipe!

See the attached picture

I found this quite shocking after only 4.5 years!

As I do not want to do this job again - How can we stop this build up?

Is there a particular cleaner we can use to prevent it?
Will regular de-scaling work?
Has anyone else had this problem?

HeadsPipe.jpg
 
I did not know it was unique to men!!

The other important action is to ensure the pipework is completely flushed of residual urine; the pump is small bore while the pipes are large and can be long. 20 pump strokes is a minimum. It can be difficult to convince the crew to do this at night /forums/images/graemlins/blush.gif
 
The clue as to why this happens is in your description of the design. The 5m of discharge pipe means that only rarely will anyone ever pump through sufficient seawater to completely flush the pipe through. You cnstantly have a mixture of seawater and human (women's is much the same as mens) urine in the pipe, precipitating carbonates like crazy.

One solution is to ask everyone to do a lot more pumping and particularly when leaving the boat to pump through a load of seawater finishing off with a bit of vinegar. A more satisfactory solution would be to create a new outlet as close to the head as possible and blank off the old one.
 
If you can get the pipe out completely it is much easier to clear it. In Spain, we bought some acid solution (cant remember which) called Aguaverte available in the supermarket which reacts with the calcium, all of which comes bubbling out of the end. We also spent many minutes 'twacking' the pipe on a concrete surface to break up the hard stuff.

Put the pipe back in, with great pain, tested it with more than just urine and blocked it again straightway. More Aguaverte down the pipe brought the whole lot flying out of the pipe all over the floor of the heads !! My mate and I just sat and laughed for while!

In hindsight, I wish I had walked to the chandler and bought a new piece of pipe.
 
Nick, if its any consolation, I had to do Full Circles last year. Took it out and banged it clear over the transom, and put it back again. A real pain, but not as bad aas yours shown.
What have you been eating? /forums/images/graemlins/laugh.gif

We usually put a mixture of coca-cola and olive oil in the pipe for 1 weekend in 4, but always leave the system full of fresh water to avoid the smell issues.

We do put biodegradeable paper down our loo with no problems.
 
[ QUOTE ]
Hydrochloric acid / Brick Cleaner, diluted as req
do be very careful with it + eye protection + rubber gloves

[/ QUOTE ]

Yes but how do you use it in practice? Shut off the sea cock? In which case will you bu**er up the fl;ap valve? Or do you simply pump the acid into the loo and leave the gasses to come out to seaward through the open ssea cock. In which case what about dissolving the sea cock?

Anybody actuall done this?
 
[ QUOTE ]
I also pump fresh water through when leaving the boat so there is fresh water only left in the outlet pipe. Pretty sure I read this tip somewhere here.

[/ QUOTE ] I read the same and we always run a good quantity through at the end of a weekend when we put the vinegar through. Male urine is a bit worse for the deposits but much much worse for the smell, it reacts with saltwater to give off amonia. Regular fresh water and mild acid flush is essential, but as has been said, flushing all the human waste through is as important.
 
I think that's a lovely picture of what the doctor sais about my arteries . . .

If in a hot climate (lots of evaporation) make sure you can access your heads pipes easily, and take the pipes off every two years to clean them out or replace them.

Hydrochloric acid only partially works, because you can't keep it in contact with the upper loops of the exit pipe near the siphon vent, so that remains narrowed. Also, a very large quantity is needed for the amount of deposit you're showing here.

I'm sure our resident chemist will come up with a description of what hydrochloric acid does to bronze . . .
 
I find it strange all this talk of making sure the system is full of fresh water to avoid smells. I've always operated on the reverse principal - never had a smell problem with sea water (which seems to have some sort of disinfectant effect), but have done with river water, so I try to remember to flush through with sea water if leaving the boat for a while.

Has my imagination been playing tricks on me all this time?
 
I always thought the smell was dead bacteria in the inlet pipe, where lack of light kills them, and they produce a sulphorus odour as they die and break down. We only get the smell when we pump the heads for the first time when the boat has sat for a week or more.
 
I recall reading that harpic ( being bleach) attacks neoprene which the pumps depend on...

Am I wrong?

Also surely 5m is excessive for a heads waste? I dread to think how many pumps it would take to clear so much volume as 5m of discharge hose, surely 20 pumps won't even clear half of it?
 
[ QUOTE ]

Anybody actuall done this?

[/ QUOTE ]Yes, for years and my father did before me for twenty years. Fill the toilet pan with water -- ideally fairly hot fresh water but cold salt is OK. Add a good teacup of concentrated Hydrochloric Acid. If it is weaker acid, use a couple of teacups. DO NOT UNDER ANY CIRCUMSTANCES MIX WITH ANY OTHER CLEANERS OR BLEACHES OR YOU WILL GENERATE CHLORINE GAS. Pump out and in the last few pumps, squirt a couple of tablespoons of vegetable oil into the pan to lubricate the works. Leave with the lid down for a few hours, if possible. This should be done every week. With this treatment you will never get a scale buildup.
 
[ QUOTE ]
Also surely 5m is excessive for a heads waste?

[/ QUOTE ]

My fwd heads is 8m.... dont forget that it has to go up to the deck level before coming back down to the hull.
 
Just a thought, but if these deposits are brittle, how would regularly working your way along the length of flexible pipe, squeezing/kneading it do to clear it. Break it all down to bits and flush through?

Just comparing this to what my kettle does. Sort of scales up and then sheds every now and then.
 
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