Vacuflush not pumping

aero3113

The head stopped building vacuum. Green light is on but nothing happens when the foot pedal is pushed, just water flow vacuum pump doesn’t come on. What should I look at first? I tried a plunger so I don’t think there’s a clog.

YYZRC

I had issues with my vacuflush on Friday. I replaced duckbills and bellows last summer so I was pretty confident that wasn’t the issue. It was a clog at the elbow where the poop enters the vacuflush “tank”. 

aero3113

Yea, nothing was flushed other than liquid and some toilet paper. I’m thinking the vacuum switch went bad. I think there’s a way to test it. But if the green light is on, that means it’s holding vacuum, correct? It’s possible there is a clog.

Aqua_Aura

My vacuum switch went bad and I ordered a new one, in my case that system was staying on and not building vacuum because the diaphragm switch had a bad seal. You can push on the switch portion of the diaphragm vacuum sensor to manually turn on the pump and then I would check for power at the pump with a test light and manually press the diaphragm switch. 

aero3113

Thanks @Aqua_Aura , I’ll try that.

aero3113

@YYZRC the only way to access is through the galley fridge, correct? The port side seat storage bin should be removable!

Aqua_Aura

If the diaphragm failed it would leave the pump on however if the switch portion failed it wouldn't turn the pump on. It's a really simple system even an aircraft mechanic could figure it out 😉 

Those diaphragm switches are surprisingly expensive. 

aero3113

@Aqua_Aura if the switch portion failed, would I still have a green light in the head showing good vacuum? Since I have the green light, why won’t it flush when I push the pedal? Would a bad switch cause that?

Aqua_Aura

Not sure what the light indicates. I don't have that. If the light is indicating "ready" as in it has vacuum than maybe your switch is stuck in the off position and that would explain why the pump is off and the light is green thinking it's ready. 

aero3113

Yes, the green light indicates “ready”. When the pump is running the red light is on and indicates “do not use”. So it sounds like it could possibly be the switch. I read that you can jump the B terminals to test the switch. 

YYZRC

aero3113 said:

@YYZRC the only way to access is through the galley fridge, correct? The port side seat storage bin should be removable!

Sadly yes, icemaker or fridge has to go. 

Aqua_Aura

aero3113 said:

Yes, the green light indicates “ready”. When the pump is running the red light is on and indicates “do not use”. So it sounds like it could possibly be the switch. I read that you can jump the B terminals to test the switch. 

I don't see why not. You would just be bypassing the switch and supplying voltage to the motor outside of the switch. 

Dream_Inn

I'm betting you have a clog.  I have the light and what sounds like the same setup.  Extremely familiar with it (FYI, if you need parts, or even an entire new unit, I have all of it to sell).  Usually if switch is bad, it will keep running as it only closes when vacuum pulls it enough to break the connection.  This wouldn't have anything to do with duck bills, again if they were bad it would keep running.  Green light usually means it is vacuumed and ready to go.  Clogs usually happen right in bottom of tank.  When you flush, does the water just stay in toilet?  If yes, turn water off, run it out in sink.  Then hold ball open and, using rubber gloves, reach into toilet and see if there is anything in the hole in the bottom.  (this happens sometimes on my boat after a make good use of it :- )

aero3113

I did some troubleshooting and jumped the switch at the B terminals and the pump came on. I then went to the toilet and tried to flush and it worked as normal but the pump did not come back on to vacuum up the system. I replaced the switch and all is good! ⚓️

earl1z19

That switch is stupid expensive for what it is but better than **** in a bucket I suppose

aero3113

Yes, cost me $162 including tax! Cheapest I could find and it was a local shop so I was able to pick it up.

mattie

Pretty much the most expensive part in the VacuFlush system.
Hate those things.

Dream_Inn

aero3113 said:

Yes, cost me $162 including tax! Cheapest I could find and it was a local shop so I was able to pick it up.

I've got a couple of them that I'd sell for much cheaper if anyone needs one. I'd sell one, but the other is on a completely rebuilt "spare" box ready to go.