Yep, another vacuflush question, the vacuum tank

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The Brockerts

Senior Member
Joined
Oct 17, 2014
Messages
263
Location
USA
Vessel Name
Moonstruck
Vessel Make
1990 Californian/Carver 48 MY
My systems is just like below. Can someone tell me about the vacuum tank? Is the tank "full of black water"? Is there any plumbing inside?, When I flush does it empty completely? Does it hold "black water" between flushes ? What is it's purpose?


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It's purpose is to build a volume of vacuum so that when you depress the pedal on the bowl the bowl is completely cleared. The force of the vacuum being pulled through the small orifice breaks up the solids, no macerator pump required. The system will not work well if at all without the tank.

After flushing t is not full of black water but some will remain. It's not a bad idea when leaving the boat to flush the system a few times to leave clean water in the tank.

VacuFlush: Get To Know The System
 
I've written a piece that I call "VacuFlush 101" that explains how it works (an amazing number of owners think they do, but don't) and how much water it really needs to prevent 90% of problems with it. I'll be glad to send it you--and anyone else who wants it--if you'll send me an email (no way to attach anything to a PM) ...I'll attach it to a reply.

And btw...I love it that you still have the original 3 separate component system instead a "vacuum generator" that bundles the vacuum tank and vacuum pump, complicating maintenance.

--Peggie
peggie.hall@gmail.com
 
Our system incoporates vaccum tank and pump into one, but these might help... at least conceptually:

VacuFlush: Get To Know The System - VacuFlush Toilet PARTS Diagrams - 508+ - Marine Sanitation & Supply


marinesan.com
marinesan.com

VacuFlush: Get To Know The System - VacuFlush Toilet PARTS Diagrams - 506+ - Marine Sanitation & Supply


marinesan.com
marinesan.com






Several consecutive freshwater flushes, including some with resting doses of something like NoFlex, can get the tank empty and "not gross" enough to work on.

-Chris
 
Our system incoporates vaccum tank and pump into one,

It doesn't...they're still separate, but "bundled" together into a "vacuum generator" to save space and make doing things like replacing duckbill a major PITA.

As for cleaning out the vacuum tank...the hoses and pump need rinsing out too. The flush water flow is too wimpy to fill the hoses, and rinse out the system. The solution: flush a full bowl of clean water once a day.

--Peggie
 
It doesn't...they're still separate, but "bundled" together into a "vacuum generator" to save space and make doing things like replacing duckbill a major PITA.

Ah, well, yes... but it's all the same "box" to take out of the boat when we need to work on it.

Not knowing any other version, it's all a PITA to me... compared to an electric macerating ter'let.

As for cleaning out the vacuum tank...the hoses and pump need rinsing out too. The flush water flow is too wimpy to fill the hoses, and rinse out the system. The solution: flush a full bowl of clean water once a day.

Yep, when I had to change our bellows (and duck bills while I was at it), I started flushing/rinsing the whole about 3 (or more?) days early, with full bowls and NoFlex or Cascade powder. Worked OK.

-Chris
 
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When I service the pump, I strip it down and soak it in muriatic acid. A simple water rinse and it’s ready to assemble.
 
It's great for all of us "amateurs" to have Peggy on TF with us - great coaching and the resources that she sends us is a great help.

It's been a while since I opined on VF, so I'll give a "Cliff Notes" version again: It's terrific. I bought a 2005 Camano in 2017 - it's now 20 years old. Total maintenance since 2017 so far is changing the duck bills - bought the cheap stuff and replaced it a month later with factory advised replacement. ("Cheap" has a way of being expensive, doesn't it!). My "good luck" has something to do with flushing after pump outs with three bowl fills of lightly soapy hot water. System stays clean smelling, functions well, and if no one breaks the "paper commandment", we have no problems. 3 second bowl water fill after paper seems to clear the paper well every time. (Paper commandment enforcement on my boat: If there is a paper clog, last VF user has to clear it.)

When anticipating a long period of non-use - a couple of months or more - I do a pump out followed with minimum water in the bowl and about a cup of veggie oil - whatever is handy, and my simple mind is convinced that doing this reduces risk of system corrosion while also lightly coating the duckbills. Also, a little oil on the pump piston seems useful at beginning and end of season, seems confirmed by quieter operation.

Hopefully mentioning good service from VF doesn't tease the Sanitation Device Demons into attacking my VF, but fair is fair - Dometic/VF merit a compliment now and then.
 
I've written a piece that I call "VacuFlush 101" that explains how it works (an amazing number of owners think they do, but don't) and how much water it really needs to prevent 90% of problems with it. I'll be glad to send it you--and anyone else who wants it--if you'll send me an email (no way to attach anything to a PM) ...I'll attach it to a reply.

And btw...I love it that you still have the original 3 separate component system instead a "vacuum generator" that bundles the vacuum tank and vacuum pump, complicating maintenance.

--Peggie
peggie.hall@gmail.com
Peggie, are the combined systems problematic? I have the old separate system but two vacuum tanks, two pumps etc does take up some space. I’ve wondered if a single integrated system would work or if the heads always need a dedicated vacuum tank and pump?
 
Peggie, are the combined systems problematic? I have the old separate system but two vacuum tanks, two pumps etc does take up some space. I’ve wondered if a single integrated system would work or if the heads always need a dedicated vacuum tank and pump?
Or go to a Marine Elegance and get rid of all the extraneous stuff since the ME is all contained in the head itself. And also loose the continual maintenance on the head.
 
I have seen two heads operating off of one tank and pump. Only problem being if you loose one you loose both. I like redundancy.
 
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