Vaccuflush Issue

[Deano]

We haven't had any issues with this system until now. The aft head flushes painfully slow without the usual vacuum noises. The forward head is on the same pump and works perfectly. I assume there is blockage somewhere but its not at the head itself.
Has anyone had similar issue and can advise me as to the most likely nasty location I should check first?
I've been running cleaning vinegar through that unit over the last couple days and I haven't seen much improvement.
Any suggestions are appreciated.

 

[seasalt007]

I made a little tool for just this issue using a plastic hose nozzle with male threads on the output end. To that I screwed a female hose mender fitting and embedded the small end into the middle (cut hole) of a mini plumber's friend.

To clear the clog, turn off the water supply to the toilet, remove all water from the toilet bowl, attach the hose nozzle assembly to your dock water hose, turn on the vacuflush pump, place your knee on the toilet pedal to hold the bottom open, place plumber's friend tightly over the hole and start blasting with short bursts of water pressure. Soon it will began sucking the water out of the bowl and it is fixed.

 

[Conrad]

We had a similar issue; judicious use of a plunger sorted it out. Rather than turn the water supply off I simply turned off the power to the toilet at the breaker (after ensuring there was vacuum).

 

[seasalt007]

For my system to work the pump has to be running for water to flow though it and so it will start sucking when the clog is cleared thus emptying the bowl.

 

[Deano]

Thanks Gentlemen for your responses. I will continue plunging, but judiciously this time. If I still meet with no success I wil try the power plunge.

 

[Deano]

Much time and judicious plunging later and no progress. Opted for the suggested power plunge and still no flow. I believe a guest last month may have deposited something of unnatural origin in that head. If no one suggests otherwise, I'm going to open the system at the vacuum tank and see what I see. Maybe give it a good dose of shop vac and see where that gets me besides disgustingly smelly.
Thank goodness for a spare head.

 

[Insequent]

My initial thought was opening at the duckbill valves. You may as well replace all four (two each side of the pump) when doing it.

But then I remembered you said two heads on one pump/vacuum tank. For my system thats a no-no, but for certain models apparently its OK.

Given your description the blockage has to be in one line, before its joins the second line. So disconnect at the join, and focus on the blocked line. Maybe just replace the blocked line as it could be kinked or have some other issue that will cause repeat obstructions.

 

[Alaskan Sea-Duction]

I believe a guest last month may have deposited something of unnatural origin in that head.

Sorry to hear. Because of the exact issue you are having, no one boards my boat until they have been "potty trained!"

I hand my guests a set of duckbills and rubber gloves. I explain everything they put in the head has to go through this little opening. They almost always ask what the gloves are for. I state those are yours to help me breakdown the system and you will get crap and pee on you!

They always get a funny look on their face. No plugged heads yet......

 

[Max Simmons]

Had same issue years ago. Aft head plugged, forward head fine. Pulled the hose off at vacuum tank and ran a small snake towards holding tank. Found blockage of "foreign object" at a fitting joining 2 pieces of hose. Luckily the snake's wire end screwed into the cotton object and held on as I pulled it out. All good after that.

 

[twistedtree]

My vacuflush had one pump per head. Are you certain you only have one pump? I ask because when one of our pumps was accidentally turned off, it behaved exactly as you describe.

In your case, it seems that the obstruction is pretty resistant to moving forward, so what about trying to pull it back? Could you release vacuum at the pump, then rig a shop-vac to the toilet and try sucking the obstruction back out the way it went down? I wouldn't want to be your shop-vac under such a scenario, but I suppose it's better than getting it all over you.

 

[Insequent]

Not sure how Deano is progressing with his issue, but I have now solved one of mine.

During my recent extended cruise the master cabin head, which is the one day guests mostly use also, started loosing vacuum. Not a huge issue as both heads have 'night switches' to stop the pump from starting up all the time. Apparently the normal cause of leaks is duck bills needing to be replaced, but in this case, at quiet times, I could hear the leak whilst in the head. So, either a loose hose or leaking floor flange. I deferred repairs until back home, then ordered parts.

A few days after the parts arrived I took them down to the boat. After a few more days of procrastinating I disassembled the vacuflush and cleaned everything up. I had to take the base assembly to my workshop at home to remove the completely rusted screw retaining the ball on its shaft. But, with new parts installed I reassembled everything and am now holding vacuum. Great success, one fixed.

Then the front head. A year or so back the bowl would not keep water all that long, so I installed new bowl seals. It is now holding water but still has a slow loss of vacuum. New duck bills, no change. New vacuum switch, no change.

Now for this head I have not been able to hear an air leak, so it may not be the floor flange leaking. If not then it is a hose leak or a perhaps a pinhole in the diaphragm pump. I now have a spare floor flange seal, but right now am not particularly in the mood to have to completely disassemble and clean another head.

Thinking back, I think that this vacuum leak has been there ever since the refit. At that time pumps were rebuilt and PVC pipe run for all but very short hose connections at the head, pump (both sides) and holding tank. The latter hoses connections were easy to check. The one at the head is really only possible to check when replacing the floor flange.

I am wondering whether I might have a very small leak from a join in the PVC pipe run. If so it might be quite tricky to locate and repair as the pipe run is mostly inaccessible. Are there any other sources of vacuum leaks that I should check before starting the floor flange seal replacement process? I am happy to procrastinate for quite a while whilst suggestions come in....

 

[Deano]

I haven't resolved the issue yet. I just had to replace the macerator pump and haven't felt like opening up the system. I will try the shopvac idea. It's a pretty easy and a much more pleasant task than opening the system again.