Vaccuflush pump runs constantly, need help

[Montenido]

Howdy folks,
I have two separate vaccuflush set ups, one forward, and one aft. Recently, the forward pump has started to run constantly when the breaker is on. I am new to this type of system, and was wondering if any of you with vaccuflush experience might be able to point me in the right direction for fixing the problem.

The fwd head appears to be functioning normally except for the pump not shutting off automatically. Suggestions?

Cheers, Bill

 

[rochepoint]

Usually the duckbills (4) at the pump, here is a link to the troubleshooting manual I posted in the library on the site .....http://www.trawlerforum.com/forums/downloads.php?do=file&id=5

 

[Montenido]

Thanks Mike,
That will help a lot!

Cheers, Bill

 

[hmason]

I had a similar problem that turned out to be a defective pressure switch on the vacuum tank.

 

[yachtbrokerguy]

Many boat builders now install a "night switch" in the head to turn off the vacuum pump so it does not run and make noise when sleeping.
This is not a repair of course but for many older boats the owners will add the switch as an in expensive temporary repair.

 

[bcam]

It seems amazing that there isn't a YouTube video about replacing the duckbills.
The only one I find has a guy talking about it, but no how-to.

 

[DHeckrotte]

Ducks resist replacement of duckbills.

Google for your correct manual; here's one: http://www.dometic.com/QBankFiles3/...Systems/VacuFlush-140-Series-Manual_11710.pdf

Read it and weep.

 

[Alaskan Sea-Duction]

Are both heads holding water and not leaking down?

 

[HeadMistress]

Howdy folks,
I have two separate vaccuflush set ups, one forward, and one aft. Recently, the forward pump has started to run constantly when the breaker is on. I am new to this type of system, and was wondering if any of you with vaccuflush experience might be able to point me in the right direction for fixing the problem. The fwd head appears to be functioning normally except for the pump not shutting off automatically. Suggestions? Cheers, Bill

First flush at least one FULL bowl of water to rinse out anything that may be preventing a duckbill valve from closing completely. If that doesn't solve the problem, the two most likely culprits are worn out duckbill valves and/or a failed vacuum tank switch. Duckbills (there are 4 of 'em, btw...2 in the inbound valve nipples and 2 in the outbound)--have an average lifespan of about two years. The vacuum switch averages 5-6 years.

Start by replacing the duckbills...it's not a difficult job--although access to the pump can make it a lot more difficult...just remove the hoses from both ends of the pump (put a plastic bag or disposable aluminum pan under 'em to catch any spills) and unscrew the valve nipples...replace the hoses.

If that solve the problem, it has to be the switch. You can order the duckbills and the switch from Dometic 800-321-9886.

Since you're new to VacuFlush you'll prob'ly find a couple of documents I've created useful. "VacuFlush 101" explains how the system works and how much water it actually needs if you want to prevent problems...the other is the trouble shooting guide that covers just about every symptom, probable causes and cures that a V/Flush can develop. I'll be glad to send 'em to you and anyone else who wants 'em if you'll send me a PM that includes your email address (can't attach anything to a PM).

Peggie
http://www.amazon.com/New-Get-Rid-Boat-Odors/dp/1892399784/
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

 

[Alaskan Sea-Duction]

Listen to Peggie she is the "Queen of poop!"

 

[bcam]

I an sure it's the duckbills that are the problem. I have a hard time believing that there isn't a guide to replacing them. I have the manual and it says rplace them with no illustrations pertaining to the replacement.

My issue is that I tend to go to far when taking things apart. Ask me how many parts there are in a 3 speed bicycle hub. Just don't ask how I know. I am sure that if I start and manage to disassemble the system, someone who I am paying to repair the system will say "If you just do this two step process, it would have been all you needed to do".

In the mean time, it is the guest head and I leave it turned off, so it doesn't keep us up at night.

 

[Montenido]

Thanks everybody for the great suggestions and links. I will try all of the above, and Peggie, a PM has been sent.

Thanks again, Bill

 

[Jetstream]

Bill we have the same system with two VacuFlush heads. I have put new duckbills in both and it is an easy job. There were only 2 in each of ours and it took about half an hour for each. I did coat them in silicon grease when putting them in as I have found it preserves the rubber in this type of sitiation. Since then we have adhered to Peggie's 101 tips for the system and had no problems,

Brett

 

[HenryD]

I was helping a sailboat docked next to us and his vacuflush pumped for about 2 minutes and stopped. We were in the engine space...not a room, just our heads in hatches. A few minutes later it pumped again. His wife heard air leaking from the toilet and poured a few ounces of bleach in the bowl. I asked why bleach and they said they used it instead of water at times. This did not sound like a good practice to me but I simply do not know - will the bleach damage the bowl seals and duckbills? Aside from the cost, that much bleach must also play havoc with the holding tank?

 

[HeadMistress]

I was helping a sailboat docked next to us and his vacuflush pumped for about 2 minutes and stopped. We were in the engine space...not a room, just our heads in hatches. A few minutes later it pumped again. His wife heard air leaking from the toilet...

An air leak in the bowl means that the "dome" is no longer sealing. That may mean that it just needs cleaning or it may mean that the kit (which used to be called the "ball, shaft and cartridge kit" but I think they've renamed it) needs to be replaced. Their use of bleach, plus I'd bet real money that they ease pedal up after use instead of just letting it go to spring back into place with enough force to seal, is prob'ly caused it to fail. He prob'ly needs to replace the duckbills in the pump too.

...will the bleach damage the bowl seals and duckbills? Aside from the cost, that much bleach must also play havoc with the holding tank?

YES...to both questions. NEVER use bleach in any sanitation system...it's not only corrosive and destructive to rubber, but also breaks down hose resistance to odor permeation. Plus, bleach and the ammonia in urine is not a good combination, especially if they're using very little flush water.

My "VacuFlush 101" article and the trouble-shooting guide from the V/Flush manual will help 'em prevent 99% of problems with it and tell 'em how to solve the other 1%, If you'll send me a PM that includes your email address (can't attach anything to a PM), I'll send them to you.

Peggie
http://www.amazon.com/New-Get-Rid-Boat-Odors/dp/1892399784/
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein

 

[bayview]

The simplest answer is often correct. before taking things apart see if the bowl holds water. If not the duck bills are not the problem, junk in the bowl seal is. do what Peggy said to flush the system.

 

[Conrad]

We are going into our third year with our newly installed vaccuflush systems.

We have had the same symptoms pop up, and the solution was exceedingly simple.

We took the toilet bowl brush and and gently (after turning off the power to the pump) moved it around the seal with the ball valve open.

That has happened twice and worked like a charm.

 

[Montenido]

Update

Hi folks,

After my last trip to the islands I finally got around to changing out the duckbills. It was quite easy, so after I finished with the forward head, which was the one running all the time, I changed out the rear head, which was working fine. You know the old adage about not fixing something if it isn't broken? Well, that is good advice. While I was messing with the rear duckbills, I noticed a drip coming from the hot-water-out fitting on my water heater. When I tried to move it, it snapped off in my hand. Now, some parts are readily available in La Paz, and some are not. This one was not. So I left the boat with a non-functioning freshwater system. Of course, there are no shut offs in place to isolate the water heater, so I am tracking down pieces to bring back on my next trip.

The rear head works better, as does the forward head, although it does still cycle fairly often, just not constantly. The projects continue...

Cheers, Bill

 

[dz1drwww]

Before I change the duckbills on my systems I squirt a few pumps of hand soap into the bowl then fill it with water and flush. I do this two or three times, then work the duckbills. If nothing else, it makes the dirty job a bit cleaner.....

 

[Maerin]

The bowl seal can get grit or urinary salts buildup on the rubber. Sometimes the solution is as simple as opening the ball by stepping on the pedal then take a finger around the underside of the rubber seal to clean it. Oh, don't be such a prude, you flushed it with fresh water first, didn't you?

To counter urinary salts buildup, white vinegar is a good preventive, it won't mess with the system, all natural! Just put a 1/2 cup in the bowl and let it stand till morning.

If cleaning doesn't keep the water in the bowl, time for a new seal like Peggy mentioned.