Vacu flush runs

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J

John R.

I recently bought a 1998 Catalina 36. In the last week, the vacu flush pump suddently started acting up; it runs without stopping unless I turn off the power to it. I don't think the problem is that the seal in the toilet is bad; I've fiddled and fiddled with that and it doesn't help. Also, it seems that this would happen gradually, which hasn't been the case in this case. Could it be that the holding tank is full? Another possibility: The last time we went out, a guest flushed some toilet paper instead of depositing it in the trash basked in the head. It's been ever since then that the pump won't stop. Could this in some way cause the problem? If so, how do I fix it? Thanks for any suggestions.
 
R

Rick9619

Vacu flush problem

John, welcome to the world of they work real good when they work. Im sure Peggy will chime in here shortly. She is the expert period. You are not building up vacuum pressure so, you have a clog or a leak. Leaks are usually self critiqing because they stink. First and foremost, pump out the holding tank and check your vented loop for clogs. Is your toilet flushing or when you push the foot pedal or do you still see water in the bowl? If you can just barely put enough water to cover the ring, cut the breaker on and see is the pump trying to build pressure ie you see the water "pulsing". If it does then your ok. Your pump isnt shot. Run your lines from the head to the vacuum tank to the pump and to the holding tank. Wherever it makes a bend make sure no line has collapsed. Next task would be to change the duckbill valves. If they are more than about two years old they have probably opened up. Just undo the lines on either side of the pump and unscrew the fittings. I put a ziplock bag and a rubber band over the open lines. They may drip a bit so have some saniwipes and wear gloves! There are TWO duckbill valves on each side of the pump. Make sure you put them in the right direction! The duckbills should always be pointed downstream! We put disolvable toilet paper in ours all the time but if someone did regular tp, the system can handle it on a case by case basis :) Just remember a three second "book answer flush" is only for number 1. Number 2 is always about eight or so depending on size... er .. yuck. We dont spare water there :) Bottom line.. your duckbills are probably shot. IT is easy to replace them. Cheers
 
Dec 2, 1997
8,915
- - LIttle Rock
The first thing you need to do is READ THE MANUAL

It describe just about every synptom, causes and cures that a V/Flush can develop. If you don't have one, you can download and print it from here: http://www.sealandtechnology.com/pdf/600340006%20VacuFlush%20OM.pdf Rick is apparently unfamiliar with VacuFlush toilets, 'cuz NONE of what he told you applies. There are only 3 things that can cause a VacuFlush pump to run non-stop: 1. An air leak in the system. The first place to look is the bowl...if it's holding water, that's not where it is. 2. The next place to look is the duckbill valves--4 of 'em, two on the inbound side, two on the outbound side--in the vacuum pump...if they haven't been changed in at least 2 years, it's time. If TP or solids have gotten caught in 'em, that'll prevent the toilet from achieving full vacuum, which would prevent the pump from turning off. 3. A failed vacuum tank switch. That switch has a sensor in it that turns the pump off when full vacuum has been achieved. If the switch has failed, the pump won't turn off. If the toilet isn't achieving full vacuum, and if the bowl is holding water, the culprit has to be one of two things: 1. Stuff caught in the duckbills. The cure: a LOT of water through the system t rinse 'em out. Fill the bowl with water and flush it a couple of times. If that doesn't work... 2, Worn out duckbills. The cure; replace 'em. If the toilet IS achieving full vacuum, the culprit almost has to be a failed vacuum tank switch. Do NOT take ANYthing apart till you've downloaded and read the manual! 'Cuz blindly tackling a V/Flush based on the kind of advice you got from Rick is likely to turn one problem into 3, 4, or even 5. If you don't find the solution in the manual, call SeaLand: 800-321-9886
 
J

John R.

no link but thanks

Thanks for the clear and rapid reply. I tried clicking on the link you provided but got a message that that page didn't exist. Then I went to the sealand web site and found where their manual is listed, but I was unable to click on it also. Maybe it's not online yet. In the meantime, I'll try what sounds like the simplest "fix" - flushing the toilet with lots of water, and see if that works. It's also possible that the former owner has the manual stashed away somewhere. Thanks again. John
 
Dec 2, 1997
8,915
- - LIttle Rock
Manual is there...the link is just too long to fit

into a forum post. I've pasted it into the space to add a link below. I just tested it and it works.
 
R

Rick9619

Hey Peggy, just a question

I know your the expert and if you remember you just helped me solve a problem with the collapsed line on my eco vac. We put the 90 coupling in it and now it works perfect. Im thick skinned so .. but that was kind of an ouch. I didnt think I was that far off. You said 1. An air leak in the system. The first place to look is the bowl...if it's holding water, that's not where it is. I said "your toilet flushing or when you push the foot pedal or do you still see water in the bowl? If you can just barely put enough water to cover the ring, cut the breaker on and see is the pump trying to build pressure ie you see the water "pulsing". If it does then your ok. Your pump isnt shot. I dont see where that isnt plausible. Will the toilet flush on the pump alone? You said 2. The next place to look is the duckbill valves--4 of 'em, two on the inbound side, two on the outbound side--in the vacuum pump...if they haven't been changed in at least 2 years, it's time. I said "Next task would be to change the duckbill valves. If they are more than about two years old they have probably opened up. Just undo the lines on either side of the pump and unscrew the fittings. There are TWO duckbill valves on each side of the pump. Make sure you put them in the right direction! The duckbills should always be pointed downstream! Where was that bad advice? I said, "Run your lines from the head to the vacuum tank to the pump and to the holding tank. Wherever it makes a bend make sure no line has collapsed." That was exactly what was wrong with my vacu flush, and after talking on the PHONE you and I came to that conclusion and fixed it. I didnt mention the vacuum switch. Might very well be the problem. But wow Peggy that was kinda harsh. Your the expert, but since I have taken the darn thing apart and rebuilt it.... gee, ah whatever. Cheers
 
Dec 2, 1997
8,915
- - LIttle Rock
You're right, Rick..it was. I apologize

I confused you with another Rick in San Diego who has a Jabsco manual and got a little panicky! To answer your questions: "If you can just barely put enough water to cover the ring, cut the breaker on and see is the pump trying to build pressure ie you see the water "pulsing"." Any "activity" in the bowl is a sign that the pump is pulling water through the bowl around the dome. If that's happening in your bowl, it means the dome isn't sealing...the seal on the underside of the hole may just need a little cleaning, or you may be easing the pedal up instead of just letting it go...one of the most common mistakes that V/Flush owners make. They don't realize that the pedal is spring-loaded for a reason: to allow the dome to snap back into place with enough force to seat it. Over time, easing the pedal up can cause the spring to develop a "memory" that won't let the dome seat tightly any more. "Will the toilet flush on the pump alone?" No...'cuz the vacuum pump doesn't flush the toilet...the accumulated "vacuum" (suction) does. The pump only runs AFTER the flush to re-establish vacuum in the system. Here's how it works: The accumulated suction pulls bowls contents only as far as the vacuum pump...the drop in negative pressure turns the pump on to do two things simultaneously...pull all the air out of the system between the bowl and the pump to get it ready for the next flush, while also pushing the bowl contents the rest of the way to the tank, treatment device or thru-hull. When the sensor in the vacuum tank switch senses that the correct amount of negative pressure ("vacuum") has been reached, the pump shuts off. So without enough accumulated vacuum in the system, the only thing that can move waste through the system to the pump is gravity. If there's a low spot in the hose between the bowl and the the vacuum tank, waste will drain out of the bowl, but only as far as gravity will take it. If it's uphill to the vacuum tank, the bowl won't drain. If there's an air leak in the system, when the accumulated vacuum drops it cause the sensor in the vacuum tank switch to turn the pump on long enough to re-establish enough vacuum. Failing duckbills--or a bit of something stuck in 'em that prevents 'em from closing tightly (which why it's important to run plenty of water through the pump after each flush)--or a dome that isn't sealing are the most common reasons for the vacuum pump to cycle between flushes for no reason. It may start with just a brief "burp" only a couple of times a day...then get longer and more often....till finally the air leak becomes big enough to prevent the system from ever reaching enough vacuum...at which point the pump runs continuously. A failing tank switch sensor can also create the same symptoms. That's an EXPENSIVE part...so you always want to rule out air leaks before replacing it. You said, "You are not building up vacuum pressure so, you have a clog or a leak." If the tank switch has failed, it can cause the pump to run continuously even though the system has full vacuum. Nor does a continuously running pump indicate a clog. As long as there's no air leak, the pump will shut off. A clog won't cause it to cycle, either...it'll only prevent anything from getting past it. And btw, it's very rare for a vacuum pump to fail unless it's allowed to run continuously for so long that it burns out the motor...which is only likely to happen if the owner is brain dead or not aboard to hear it running. They do wear out after 15-20 years, and flushing a sharp object can put a hole in the bellows (which causes a whole different set of symptoms)...but a failed pump is almost never the cause of most problems. "Leaks are usually self critiqing because they stink." Nope...'cuz air is being pulled INTO the system through an air leak...it's not being pushed out. Permeated hoses would be the most likely source of any odor around the system. That's where I stopped reading your reply and jumped in with both feet, thinking you were the Jabsco owner. If I'd kept reading I've have seen that you did give good advice about the duckbills, especially the part about making sure they're aimed the right direction. If you don't have to remove the pump to change 'em, it's not hard to get 'em in right. But if you have to remove it, only the arrows on the pump provide a clue to which end is "in" and which end is "out"...making it all too easy to set it down backwards. I know, 'cuz I've done it. That's simple to correct, though--although taking the hoses off again and putting 'em back after turning the pump around can be a PITA...UNLESS you've already put everything back that had to be removed to get to the pump before testing the system. Lesson learned: always test the system immediately after any repair or maintenance before you put the hose clamps on and/or put anything else back.
 
R

Rick9619

Peggy ya saved my ego... thanks

Yeah I was wondering about the tank flushing on pump alone. Mine wont so you were right again. And I agree, the vacuum breaker, based on what his symptoms were, would probably be the last thing I would check because replacing it is gonna have to be done professionally and be probably a high dollar fix. I guess I was on the wrong track about the leak. You schooled me on permeation. I was thinking along the lines of an airleak, when the system is not energized, and a full bowl and lines would probably drip somewhere. Im betting, and I hope John gets back with us, is that his duckbills are shot. After I put the 90 bend in my system as you and I talked about, AND changed the duckbills, it works fantastically. And the manual, I agree with you, although i have read mine about 20 times. They lay out the schematic in a perfect world.. lol.. not a boat. And the trouble shooting is hilarious. Toilet wont flush.. check DC power, clog in lines, holding tank full.. DUH! Peggy, sweet of you to apologize but I would rather have an adult beverage with ya sometime. By the way, I just ordered the T series discharge pump. And your link was the best price. I will be in touch as to how we should integrate it into the system. Im going over on the 5th. Will pull the lazarettes and take some pictures for you to look at. No harm no foul Cheers
 
Dec 2, 1997
8,915
- - LIttle Rock
Oops, you're confusing two different parts

The vacuum breaker is part of the flush water intake plumbing that protects the fresh water system. It's located at the back of the bowl and has nothing to do with anything in the outgoing side of the system. The vacuum tank switch is located on the end of the vacuum tank, and is actually easy to replace. But the part itself costs an arm and a leg, so you don't want to buy one unless you have to. I'll be glad to help you figure out where to install your new T-Pump...give me a shout when you're ready.
 
D

Don

Thanks for the info everyone!

Thanks Peggy and Rick. I was surfing the net looking for information as to why my vacuflush keeps pumping and doesnt cycle off anymore. You guys gave me alot of information reading through the Threads. I downloaded and printed the manual and have a pretty good idea where to go to fix my problem this weekend (duckbills). I'll let ya know how it turns out. Thanks again. Don
 
D

Don

Life is good

Thanks again to all. Succesfull head repair with duckbill replacement. Thanks for all the information everyone. There's just nothing quite like a functional head. :)
 
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