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Topic: Vacuum Toilet Problems (Read 1356 times) previous topic - next topic

Vacuum Toilet Problems

I am having problems with our Magnum Opus Toilet and Vacuum System.  Basically the toilet will pump up to full vacuum and work normally most of the time.  But about ten percent of the time, the toilet will pump up to full vacuum and despite being at full vacuum the red light (Do Not Flush Light) will remain on steady or blink three times.  The green led Do Not Flush Light on the control board also repeats the sequence.  When the red light is on steady the service switch does not work to open the ball.  I have to turn the system off and back on using the Vacuum Flush remote panel to get the service switch to function.  When the light is flashing three times the service switch will work.  When the service switch is used there seems to be plenty of vacuum. Normally this will fix the problems for a while.  I looked at the Magnum Opus service manual and then is no error code listed for three blinks. This is getting to be a pain the neck. I have not called anyone yet and thought I would check with the forum first to see if anyone has any ideas.  I did not want to do any rebuild or major service of the system until we are settled for a while in one place.  Any ideas out there?
Jeff, 2002 U320, one slide. Used to full time, 125,000 miles on the clock.

Re: Vacuum Toilet Problems

Reply #1 –
js,

You don't have any info on the age of your coach, even though you think you have good vacuum have you ever replaced the duck bill valves?  Also is this happening at high altitude?  Altitude has an effect on vacuum. There is a great post by Steve on the ins & outs of how to service the system. You can check it out here  VacuFlush Toilet Vacuum Pump Rebuild  Hope you find some info there.

Pamela & Mike

You might think about adding some more info on your coach to the signature area.
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Vacuum Toilet Problems

Reply #2 –
I have spent more time getting "up close and personal" with our Vacu Flush Magnum Opus (Turbo Turd 3000) commode than I like to think about.  Our toilet definitely does not like high altitude, although it eventually builds up a vacuum and works normally.  I will tell you that the wires that lead into the control board that "hangs" on the back of the toilet innards are very touchy, and I have had them come loose.  At one point, I turned off the breaker to the toilet (at the foot of the bed) and when I lifted out the panel to examine it, one of the main power wires came completely off.  I have made sure that every wire to every connection is firmly anchored, and we have been good for a while.  One problem I have is with their customer service.  Dometic has purchased the Sealand stuff, and you must call them for Customer Assistance.  To order parts, they will tell you the distributor in your part of the country.  I ordered the seals and duckbills I needed and we have replaced a few parts.  If this thing goes, it is going to be cheaper to replace the entire toilet than to replace a circuit board.  I know there is a lengthy report on a sorry week we spent dealing with our commode ... I hope you have better luck!!
Carol & Jeff Savournin
Usta have a '93 U225 36', Usta have a '95 U320 40', Usta have a '02 U320 40'
Usta have a 2006 Born Free, Usta have a 2011 Phoenix Cruiser
Usta have a 2012 Jeep Wrangler Unlimited 4dr
"Your time is limited, so don't waste it living someone else's life."  Steve Jobs

Re: Vacuum Toilet Problems

Reply #3 –
Is your toilet over the tank. Does it need the vacuum flush to move the waste.  I had an electronic toilet that I changed to a standard old fashioned drop toilet.  It works much better.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: Vacuum Toilet Problems

Reply #4 –
Thanks for the replies.  We have a 2002 Foretravel and the black tank is not under the toilet thus the vacuum toilet is required.  Two years ago we had the pump rebuilt and the duckbills replaced.  We are in Tucson now (3,800 feet).  The problem has occurred at all altitudes including sea level.  We have summered in Durango Colorado (7,000 feet) in the past and had no problem.  I was writing to the forum because of my inability to get any help from Sealand/Dometic.  I have checked all the plugs behind and under the toilet and they appear to be okay.  So thanks for the suggestions.
Jeff, 2002 U320, one slide. Used to full time, 125,000 miles on the clock.

Re: Vacuum Toilet Problems

Reply #5 –
Quote from: jspunches –
But about ten percent of the time, the toilet will pump up to full vacuum and despite being at full vacuum the red light (Do Not Flush Light) will remain on steady or blink three times.  The green led Do Not Flush Light on the control board also repeats the sequence.  When the red light is on steady the service switch does not work to open the ball.  I have to turn the system off and back on using the Vacuum Flush remote panel to get the service switch to function.  When the light is flashing three times the service switch will work.  When the service switch is used there seems to be plenty of vacuum. Normally this will fix the problems for a while.  I looked at the Magnum Opus service manual and then is no error code listed for three blinks.

The older MagnumOpus owner's manual below, page 12 says 3 blinks means insufficient vacuum.  If it seems like you have decent vacuum, it could just be a flush ball seal in the toilet or the vacuum switch on the vacuum generator.

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There are 2 different versions of this manual.  One is dated 2004 for the 3000 and labeled with the Dometic brand.  The other is older (2002, one which does not say Dometic on it) for the 3006, 3008, and 3048.  I do know the control board changed somewhere around 2004.  Check the page on the board LEDs to see which manual applies to your control board.

Here is the newer one

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Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Vacuum Toilet Problems

Reply #6 –
Further, from the newer manual

TROUBLESHOOTING
A volt/ohmmeter (VOM) and the Toilet Wiring Diagram may be required for this section.
Caution: Portions of this section will require that power be applied to the toilet. Keep hands away from
the flush ball, motor drive arm and rotor shaft to prevent personal injury during testing and troubleshooting.
The control module uses a microprocessor to provide all the automatic and timing functions. The control module is on the right side under the access cover on the top of the toilet. The control module has input and output status lights that can be used in troubleshooting the toilet.

The program in the microprocessor monitors the input and output signals during a normal flush cycle. If the inputs or outputs do not follow the commands of the program, then the microprocessor may go into a "standby" mode and flash an "error code." The microprocessor is reset by placing the Mode switch in the SERVICE position temporarily, then returning the switch to the NORMAL position.

A safety circuit in the control module monitors flush ball operation. If foreign objects or low voltage prevent the flush ball from closing, this circuit prevents personal injury or damage to the flush valve motor. If this condition occurs, reset the control module by placing the Mode switch into the SERVICE position temporarily, then returning it to the NORMAL position.


Given 3 blinks, "Insufficient vacuum in system"

Check the "HI VAC" status light. If the light is off, the signal from the vacuum switch located on the vacuum generator or vacuum tank is absent and preventing the toilet from flushing in the NORMAL mode. Check
for loss of power to the vacuum generator or vacuum pump. Check for loose or defective wiring between the vacuum switch and the toilet.

Who knew a voltmeter could come in handy for troubleshooting a toilet? :))
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Vacuum Toilet Problems

Reply #7 –
Does the water remain in the bowl or does it gradually suck down?  One issue we had was mineral build-up on the rubber seal that rests on the half ball valve. It can flake off and prevent achieving a vacuum.  There is stuff you can buy from Sealand that is a sort of gel that is supposed to help dissolve and help get rid of the calcium or mineral buildup.  If the previous owner never addressed the mineral issue, it could be causing a problem.
Carol & Jeff Savournin
Usta have a '93 U225 36', Usta have a '95 U320 40', Usta have a '02 U320 40'
Usta have a 2006 Born Free, Usta have a 2011 Phoenix Cruiser
Usta have a 2012 Jeep Wrangler Unlimited 4dr
"Your time is limited, so don't waste it living someone else's life."  Steve Jobs

Re: Vacuum Toilet Problems

Reply #8 –
Just another thought ... If the commode thinks that your black tank is full, it will not flush. Perhaps there is an issue with that sensor connection that is requiring a "reboot" to work properly?
Carol & Jeff Savournin
Usta have a '93 U225 36', Usta have a '95 U320 40', Usta have a '02 U320 40'
Usta have a 2006 Born Free, Usta have a 2011 Phoenix Cruiser
Usta have a 2012 Jeep Wrangler Unlimited 4dr
"Your time is limited, so don't waste it living someone else's life."  Steve Jobs
 

Re: Vacuum Toilet Problems

Reply #9 –
Again thank you for the responses.  The new Manual was one I did not have and was helpful.  The water level in the Toilet is not falling when the Low Vacuum error code shows up.  I am thinking that there is something electrical going on down in the bay.  I have checked the wires as much as I can here but cannot find anything,  The most troubling problem is the non-blinking error light that cannot be reset with the service switch until the off/on switch is cycled.  This is more problematic than the Low Vacuum error.

Thanks again
Jeff, 2002 U320, one slide. Used to full time, 125,000 miles on the clock.