Vacuflush Blowing Fuse

[LowNSlow77]

Has anyone ever had the problem of the vacuflush toilet blowing its fuse when the vacuum pump is turned on? The problem is in the forward head so we have been ignoring it for some time. We started to look at it as we were on on the boat and having to share our head with my son is getting old.

We have changed the duckbills and the bellows along with its gaskets but still when we replace the fuse behind the switch for the vacuum generator it starts to run, quickly begins to slow down and pops the fuse.

I have even gone so far as to use a plunger. My wife can hear water getting to the holding tank when I use the plunger. I have reached into the toilet and confirmed there is no blockage at the base.

The other toilet has a separate vacuum generator and is working fine. It does share the same holding tank so I am assuming it is not a vent problem.

Hopefully someone has an idea that I have not thought about.

On the upside I am alot more familiar with my vacuflush system now and there did not seem to be much in the way of fecal material in the liquid we have dealt with.

 

[HeadMistress]

The two most common reasons for a VacuFlush to blow a fuse or trip the breaker are a blocked tank vent or a clogged vacuum pump--either the bellows or the duckbills, or both. The tank vent is easy to clear, scrape out the vent thru-hull with a screwdriver blade or whatever you have handy that works—which may require removing a screen but that’s ok ‘cuz screens actually create more problems than they solve. Then back flush the vent line with plenty of water. You can prevent future tank vent blockages by back flushing it every time you wash the boat and/or pump out.

Fixing the vacuum pump requires taking the pump apart to clean it out (and also replace the duckbill valves—4 of ‘em, two in, two out), so this is a problem that’s a lot easier and considerably more pleasant to prevent than it is to cure. If someone hasn't flushed something they shouldn't have, it's a certainty that you aren't putting enough water through it. Over time that will cause waste and toilet paper to build up in it till it finally jams up the bellows. And when the bellows can’t move, it causes the motor to overheat and trip the breaker.

Other possibilities include loose or broken electrical wiring or the gear motor worn or defective.

I've written a piece I call "VacuFlush 101" that explains in detail how the system works (an amazing number of owners think they know but actually don't) and how much water it needs to keep it working...I'll be glad to send it to you--and anyone else who wants one--along with the trouble shooting guide from the owners manual if you'll send me a PM that includes your email address (can't attach anything to a PM).

Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

 

[LowNSlow77]

Peggie,

The baffling part is that I changed the duckbills and the bellows and there were no clogs. I changed them anyway since we were there.

I also thought about the venting, but the other vacuflush toilet relies on the same vent and it is working fine.

 

[LowNSlow77]

Peggie,

My wife has asked me to ask you about the vented loop after the vacuum generator. Could a defective vent on the loop cause the motor to blow the fuse? We cleaned the vent on the loop but are not sure if it is working correctly at this point.

 

[HeadMistress]

A vented loop is just a piece of pipe that's a 180 sweep. The air valve (if there is one, not just a hole in the nipple on the top of the loop) only opens and closes to break a siphon. Neither the air valve nor the open hole has any impact whatever on whether anything can pass through the loop, only on whether it can break a siphon. So unless a buildup of waste and/or TP has created a blockage in the loop itself, the answer to her question is no.

However, I don't know why you'd need a vented loop in the system unless it's it's either an uphill run from the vacuum pump to a tank that's too far from it, leaving waste in the line to run back to the vac gen without one or there's a y-valve in the discharge line that allows direct overboard discharge. But both open up some possibilities...

The suction only moves bowl contents to the vacuum pump...the pump pushes it the rest of the way to its destination while it simultaneously pulls the air out the system between the bowl and the pump. It only runs until the sensor in the vacuum switch says it's achieved the necessary amount of vacuum. If that's not long enough to let the pump move the entire flush to the tank or thru-hull, what's left will sit in the discharge hose between the loop and the tank till it's pushed further along by the next flush. If too little water is going through behind each flush to rinse the system and you're not flushing a bowlful of clean water through it at least once a day either, waste can build up in the hose between the loop and the tank till it creates enough back pressure to blow the fuse, if not yet a total blockage. And from your description of what's happening, it sounds like that's likely to be the problem. See #14 in the troubleshooting guide I sent you along with the VacuFlush 101 doc.

 

[LowNSlow77]

Okay that sounds logical. There is quite a long run from the vacuum generator to the holding tank, and the discharge into to the holding tank is above the vacuum generator.

I guess the question now becomes how do we clear the hose that has clogged? I know a snake is not recommended, and chemicals are not supposed to be used, but is there another option?

 

[LowNSlow77]

Peggie,

For some reason there is a difference in your reply on the forum as to the notice I received by email. In the email it indicated that "There aren't any fuses in a V/Flush, so I'm guessing you mean it's tripping the breaker."

Oddly enough my vacuflush does have a fuse. Each head has a switch to turn on the vacuum generator associated with that toilet. The switch has a fuse immediately behind it. The second vacuflush toilet works fine even after the fuse in the forward head has blown.

Not sure if that makes a difference, but wanted to make sure that the quirks of my system were not part of the problem.

So my system has a vent loop and fuses that are not part of the standard system. I guess you can tell it was a later installation and not a factory install.

 

[HeadMistress]

There is one product that's safe to use: Sew Clean Sew Clean (pronounced "soo clean" as in the first syllable in "sewer").

Since you can't flush the toilet, you're gonna have to take some hose connections apart. The most likely place for the blockage is the one from the loop to the tank, so tackle that one first...removing it from the loop shouldn't be too messy...it's the high end. It helps that the toilet hasn't been in used in a long time, so what's in the hose should have dried out. No reason you can't use a snake here either. If you do, also use the Sew Clean to completely clean out the hose. Read and FOLLOW the directions...contact the company if necessary...they're very responsive. After you've cleaned out that line, tackle the one from the pump to the loop...if flushes couldn't get over the loop, they ran back down to the pump. You can use a snake here too. You've already disconnected the discharge hose on the pump to replace the duckbills...if nothing ran back out, anything that's in that hose has dried out.

If this doesn't work, it's time to talk with Dometic/SeaLand 800-321-9886


Oddly enough my vacuflush does have a fuse. Each head has a switch to turn on the vacuum generator associated with that toilet. The switch has a fuse immediately behind it. The second vacuflush toilet works fine even after the fuse in the forward head has blown.

The switches in the head are "night switches" that allow each toilet to be turned off without having to turn them off at the breaker. The fuse is only wired to the switch...has nothing to do with the toilet except to cut power to it.

 

[HeadMistress]

For some reason there is a difference in your reply on the forum as to the notice I received by email. In the email it indicated that "There aren't any fuses in a V/Flush, so I'm guessing you mean it's tripping the breaker."

For some reason there is a difference in your reply on the forum as to the notice I received by email. In the email it indicated that "There aren't any fuses in a V/Flush, so I'm guessing you mean it's tripping the breaker."
I edited that out after a quick check of the manual for the vacuum generator revealed I was wrong. There aren't any in the older systems that have 3 separate components--bowl assy, vac tank and vac pump...when I realized you had vac generators I grabbed the manual for them and found yours does. So I made a quick edit to correct my error. Apparently the email went before I had time to do that.

And now I'm not sure whether my reply above refers to a "night switch" or the fuse you're blowing. This reads like the description of a night switch..

Each head has a switch to turn on the vacuum generator associated with that toilet. The switch has a fuse immediately behind it.

Now I'm not sure whether it is or not...or whether that's the fuse you're blowing.

 

[LowNSlow77]

Okay, it's called a night switch. I learn something new every time I look at this.

There is a fuse behind the night switch and that is the fuse that is blowing. When we use that switch the vacuum generator starts up, but quickly begins to labour and shortly that night switch fuse blows. I am not sure how much difference that makes.

One other question. Is there a preferred place to buy your book in Canada? Need to bone up on the system generally.

 

[Alaskan Sea-Duction]

If the duck bills and pump bellows has been changed, then it could be the pump it self. Here is where I get my parts from:


Marine Sanitation - Marine toilet experts

 

[HeadMistress]

There is a fuse behind the night switch and that is the fuse that is blowing. When we use that switch the vacuum generator starts up, but quickly begins to labour and shortly that night switch fuse blows. I am not sure how much difference that makes.

OK...it IS the vacuum pump that's blowing the fuse. At least one of the 6 probable causes listed in #14 in the trouble-shooting guide (scanned from the owners manual) I sent you has to be the culprit. We've eliminate all of 'em except a blockage in the discharge line....so my money is still on that one.

Nautical Mind is a Canadian bookseller that carries my book. However, if you can use the kindle edition, Amazon is the only source. You don't have to have a kindle device...all you need is the kindle app on a smart phone or tablet. Title of my book in my signature is the link to Amazon.

 

[ranger58sb]

There is one product that's safe to use: Sew Clean Sew Clean (pronounced "soo clean" as in the first syllable in "sewer").

Peggie, do you know the difference in concentration (if any) between Trac's Barnacle Buster and their Sew Clean (Raritan's C.H.)?

Checking MSDS for each, both say phosphoric acid, but I haven't found (or understood) the percentage of acid in their solutions. Comparing non-pre-diluted versions...

The BB instructions say to dilute 4:1. The SC instruction say to delete between 5:1 and 8:1.

Do you think BB diluted to between 5:1 and 8:1 would pretty much be/act the same as SC?

BTW, does scale (uric acid, struvites, etc.) harden when exposed to more fresh air than usual? Our electric freshwater system, which had been working fine, seems to have acquired a hard clog after the discharge hose was standing open for a week or so (while I was waiting for new screws to use when changing the joker valve).

-Chris

 

[HeadMistress]

Peggie, do you know the difference in concentration (if any) between Trac's Barnacle Buster and their Sew Clean (Raritan's C.H.)?

I suggest you ask them...Email and phone numbers on their website here:
https://trac-online.com/product/sew-clean-®

BTW, does scale (uric acid, struvites, etc.) harden when exposed to more fresh air than usual?

Anything that can't just evaporate will harden when allowed to dry out. However, struvites don't have to dry out to harden...buildup is very common on holding tank walls in RVs with toilets that use very little flush water to dilute them.

I think you'll find this wikipedia article on struvites in the human body and in waste water treatment informative: Struvite - Wikipedia article

 

[ranger58sb]

Yeah, been trying that... waiting for a call-back...

-Chris

 

[ranger58sb]

Called them again, got through...

Their answer is that the two products are basically the same but BB also has some algaecides added to target marine growth. And yes, I can use it for sanitation hoses, using the SC instructions and dilution recipe (e.g., from 5:1 to 8:1) and letting it sit for 12-14 hours, copious flushing afterwards, repeat if necessary.

I hadn't originally considered that any scale present in the hoses would likely dry out and maybe become a hard clog. Trying to figure out how a previously well-working system could go so far south without even having been used... has been messing with my mind for a few days.

Interesting article on struvites; thanks for that, Peggie. 'Splains a bit about our cat's problem, and her special diet, too.

-Chris

 

[HeadMistress]

Thanks for that information...I've saved it to my files for future reference.

I have TWO cats on a special urinary cat food...d'd stuff costs a fortune!

 

[ranger58sb]

Thanks for that information...I've saved it to my files for future reference.

I have TWO cats on a special urinary cat food...d'd stuff costs a fortune!

Yep! Deb orders cat's food in from somewhere, periodic deliveries... Cat also has to come with us onboard now, since she also developed a thyroid thing and needs meds 2x/day... but at least she seems content enough. Doesn't seem to care for the engine noise, but tolerates it well enough.

Yesterday's BB treatment (following SC instructions, and 5:1 dilution) seems to have made significant progress against the hard clog in our discharge hose. Good thing, too, since it's raining buckets and we weren't relishing trips down the dock to the marina heads!

-Chris

 

[C lectric]

Some of those deposits do not have to dry out. The scale will coat the hose/piping ID slowly closing the effective ID to a point where things simply cannot work well.
Then a wad of toilet paper or whatever can finish the clog.

 

[ranger58sb]

Some of those deposits do not have to dry out. The scale will coat the hose/piping ID slowly closing the effective ID to a point where things simply cannot work well.
Then a wad of toilet paper or whatever can finish the clog.

We hadn't flushed with anything other than freshwater during all this, mostly just as test flushes... but I think our system might have been close to the self-constrict phase anyway, and we maybe just hurried it along by letting it dry out.

Yet another learning experience.



-Chris

 

[LowNSlow77]

I thought I would come back to the thread to give a follow up to what the problem was in case anyone looks at this in the future. The problem that started this was the fuse blowing in the night switch on our vacuflush. As the discussion above notes the thought was that there was a blockage in the line to the holding tank. In the end that was correct and I was able to dislodge the blockage by using an old garden hose with the end cut off. It was flexible enough to get into the pipe, but stiff enough to deal with a clog.

But that was not the only problem in the end. We ended up bringing in a vacuflush specialist as there were still issues. It turns out there were also problems with the pressure switch on the vacuum generator along with a fault in the night switch as well. We are at the point where the system is rewired from the the vacuum generator to the night switch which has been replaced, and a new pressure switch is on order. The system does work with a used pressure switch, but that used pressure switch introduced a vacuum leak so we are getting a new switch installed.

So I guess the moral of the story is that your problem may actually be a series of problems so keep an open mind. On the upside, or downside, my wife and I now have a much better understanding of the system and an intimate knowledge of the bilge. I think there might be a time when we get rid of this system in favour of a new one like the Masterflush toilet to deal with some of the quirks of our system, but for now it appears to be working. (Knock on wood)