Vacu-Flush Issue

[Flytrade]

I recently had my vacu-flush head system worked on with new duckbill valves and toilet seals. All worked fine until I used the toilet one time on a recent trip. Now the system cycles about every 3 to 5 minutes.
I can't imagine anything can be wrong with the toilet, so the problem must be in the duckbill valves. If this is the case, is there anything I can put into the toilet to clear the valves, or am I looking at this all wrong?

 

[Sublimetime]

You are losing vacuume and that is causing the pump to cycle.
Does the bowl still retain the water during these cycles? If so , and you do indeed have all new duckbills than you probably have a leaking hose fitting, or a leak in the diaghram on the pump, or a leak around the foot pedal shaft.

listen very carefully along the entire line and you may hear the hissing.

 

[superwa]

Also sure that the new toilet seal is good? Somewhere there may be a leak

 

[hottoddie]

Do you use marine type toilet paper? Who did the work? Duckbills need to be installed correctly or they will deform and not seal correctly.

 

[Luna Sea]

also had same problem, it was seal around vacuum pump and black water tank.

 

[mobocracy]

Had the same problem and determined it was the threaded piping around the vacuum pump that was leaking air. Tightened up the piping and it's worked fine.

You can usually tell if the seal at the toilet is OK if it holds a uniform amount of water. A bowl valve leak will take water with it.

I'm most concerned long term about the hose from head to vacuum pump. I had to replace my pump out hose two years ago because it was badly permeated and I could not pump out (a bilge full of septic water is an awful way to find out..). But so far, haven't had any signs of permeation on that hose.

 

[The Bill Collector]

I recently had my vacu-flush head system worked on with new duckbill valves and toilet seals. All worked fine until I used the toilet one time on a recent trip. Now the system cycles about every 3 to 5 minutes.
I can't imagine anything can be wrong with the toilet, so the problem must be in the duckbill valves. If this is the case, is there anything I can put into the toilet to clear the valves, or am I looking at this all wrong?

Contact your vender ASAP... They installed and they should fix it.

 

[Marc Rainaldo]

In the pot you have a component with 2 o-rings. This was my problem on both of the vacuflush toilets.

 

[DougLas]

Try filling the toilet with hot water the hotter the better. Then flush the head

 

[Irie308]

In the pot you have a component with 2 o-rings. This was my problem on both of the vacuflush toilets.View attachment 76038

Yup, i had the same issue. I was able to find this by turning everything off on the boat and listening for the hiss of the vacuum sucking air.

 

[endless seas]

Temp fix is to tap the vacuum motor gently it will stop the cycling.

 

[Flytrade]

Had the same problem and determined it was the threaded piping around the vacuum pump that was leaking air. Tightened up the piping and it's worked fine.

You can usually tell if the seal at the toilet is OK if it holds a uniform amount of water. A bowl valve leak will take water with it.

I'm most concerned long term about the hose from head to vacuum pump. I had to replace my pump out hose two years ago because it was badly permeated and I could not pump out (a bilge full of septic water is an awful way to find out..). But so far, haven't had any signs of permeation on that hose.

I would up tightening the pipin as you did, and that seems to be working.

 

[Flytrade]

Try filling the toilet with hot water the hotter the better. Then flush the head

I did this a couple of times, but it didn't work. However, I like the idea and will keep it for future use. Thanks.

 

[mobocracy]

I would up tightening the pipin as you did, and that seems to be working.

Good news. I had done a complete refit of the vacuum pump (duck bills, gaskets, and pump bellows) the year before and I was annoyed that it stopped working again. I stripped the pump assembly down again and couldn't find anything wrong -- the duckbills were fine. I reassembled it and still wasn't getting a decent vacuum and was pretty frustrated, and tightening the fittings was a desperation move and it worked.