vacuflush descaling

[Muaddib1116]

I just spent all morning head first in a hole rebuilding a Sealand Vacuflush VG2 and it wasn't the most fun I've had. The duckbills between the bellows and the vacuum tank had gotten stuck open with some mineral build up. Since I have a fresh water head system, the internet suggests it is uric scaling. What's a good product that I can run through the system to try to break up and disolve this, without doing a full disassembly and soak? I ran across suggestions for Sew Clean, but then of course found comments that this is just expensive diluted phosphoric acid. Any suggestions?


On another branch of the preventative behavior tree, I think based on some old posts of Peggie's that I found, that I wasn't running enough water through, and I wasn't holding the bowl valve open long enough, so waste was sitting in the vacuum tank and probably the duckbills. I will be holding the flush pedal down much longer and also performing more rinsing flushes, to help prevent buildup.

[tkeithlu]

Wasn't that fun? One of my oldest and least pleasant cruising memories is rebuilding a manual Jabsco toilet after someone, widely suspected but never proven to be the admiral (my sailing friend's mother) swallowed the pits in our cherry dessert the night before.

Maybe Peggy will arrive with expert advice, but until then, if it really is uric scale, that's lime, and vinegar will dissolve it. And, yes, clearing the pipes could keep you from having another morning like this one.

[peghall]

I'll be glad to send you--and anyone else who wants it--my article "VacuFlush 101" that explains how it works (an amazing number of owners think they know but actually don't) and how much water it actually needs to keep it trouble free if you'll either send me a PM that includes your email address (no way to attach anything to a PM) or better yet, an email (just select email instead of PM).


While vinegar--use only distilled white vinegar--won't dissolve mineral and urine crystal buildup (actually it will, but it's so labor intensive it isn't worth the effort), a weekly cupful--no more than two--of undiluted vinegar flushed all the way through the system, followed by about a quart of clean fresh water after 45-60 minutes, will PREVENT mineral and urine crystal buildup in hoses and duckbill valves. Never leave vinegar sitting the bowl of other toilets or in a VF system because soaking in vinegar will cause soft rubber (joker valve, duckbills) to swell and distort. That's why it's important to rinse the vinegar out after 45-60 minutes.


--Peggie

[Muaddib1116]

Thanks Peggie! I actually got your article from you in the fall, but I think I missed somethings in the last paragraph, which I've now read.


I will start doing a weekly vinegar flush. I assume I should turn the water off, and empty the bowl/VG before flushing the vinegar? and then hold the pedal down so that it pulls the vinegar all the way through?

[Ded reckoner]

I'm sure Peggie has forgotten more than I've learned about these systems. But, here's my two cents worth.

We use our system daily. I replace the duckbill valves every year. In my estimation, with our use, these can't go two years. I've never had to replace the toilet bowl ball valve. I only replace the head seals as needed.

I've never found anything to descale the internal parts. I haven't tried extremely caustic or acid solutions because I don't want to inadvertently hurt the system. But, I've tried a lot of solutions.

If you're on the dock, then running lots of water when flushing sounds reasonable. But, if you're out and about, that likely won't do because you will have to make a lot of water (or hauling it in) and have to deal with a holding tank that fills up quickly. More to the point, in my experience, extreme flushing helps some but won't stop scaling. If you tore apart your system to notice the condition of your bellows and inside the bellows assembly, you will not be happy seeing the scaling that's occurred.

A service provider in St Pete recommended just replacing the entire pump assembly (which sits on top of the tank assembly) every couple/few years.

[peghall]

No. Turning off the water is a good idea, but that's all you should do before a vinegar "treament." Stepping on the pedal releases the vacuum and creates suction that pulls bowl contents all the way to the vacuum pump.So stepping on the pedal is ALL you need to do until you're ready to LIFT the pedal to bring in about half a bowl of rinse water (turn the water back on first) and then step on the pedal to send it all the way through to the vac pump.


--Peggie

[peghall]

I've never found anything to descale the internal parts.

Scale is the result of using too little water. Although the SeaLand/Dometic claim that it can use "as little as" 1 pint of water is way too little, it's not necessary to use a lot more than that. You can get away with holding the pedal down only 3-4 seconds following urine only if you always add at least a quart of water to the bowl ahead of solids and hold the pedal down 7-10 seconds to flush solids, and flush a full bowl of water through once a day. That MIGHT increase your water use a whole about 3 quarts/week...One whole gallon if you use the vinegar treatment I described in a reply to someone else to prevent scale.

That service provider in St Pete just wanted to sell $500 vac pumps! Replace parts in them--motor, eccentric, bellows--only as needed.

Fwiw, VF was the toilet on my last two boats and I was a dealer for nearly 10 years. So I am intimately acquainted with 'em!

-Peggie