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Topic: Macerator toilet system to replace entire vacuflush system (Read 15395 times) previous topic - next topic

Macerator toilet system to replace entire vacuflush system

I am starting research into replacing the entire vacuflush system in basement and the Dometic/Sealand Magnum Opus model 3048 toilet with a macerator toilet.

 If I do the changeover it will either be this fall, or next year or two.  Our vacuflush basement mounted pump system and toilet are both working fine right now, so no hurry.  Quite a bit of noise with the vaccuflush, both from the toilet and from the pump in the basement.  Macerator would be quieter, and replace a aging system before it eventually has some type of failure.

Initial research shows a Dometic Masterflush 8700 series macerator toilet has nearly the same footprint (which is what we want), requires 20 amp service  and 12 gauge 12 volt wire.  Our current toilet has 12 gauge wiring to it, even though the vaccuflush toilet only requires 14 gauge and 7-8 amp fusing.

So the wiring is sufficent, but I need to check the fusing or breaker that serves the 12 gauge wiring and toilet.

We have a hamper behind the toilet with a false floor, so pretty good access to wiring and piping.  Under the bath sink in the counter, there is room for changing out vacuflush monitor to either a status panel for a macerator toilet with flush handle, or a remote flush controller for a macerator toilet without flush handle.

The remaining thing to determine inside the bathroom is the size of the discharge piping and water input piping size, to see if it will work as is or must be modified.  Also location of discharge and input pipes to macerator toilet (should be close).

In a bit I will discuss the basement vaccuflush pump system and piping that will have to be changed or modified.

Current system in diagram.

Re: Macerator toilet system to replace entire vacuflush system

Reply #1 –
I can see the following additional advantages to the swap out:

No more duckbills to replace every 3 years (I would guess the macerator system doesn't use them)

RV service folks are MUCH more familiar with macerator toilets (at least one toilet in every bath and a half DP is a macerator model) than VacuFlush systems.

ETA the one downside is you'll use more water/fill the black tank faster with a macerator toilet.  Just something to consider if you boondock or frequently do W/E-only sites.

Re: Macerator toilet system to replace entire vacuflush system

Reply #2 –
Quote from: Michelle –
I can see the following additional advantages to the swap out:

No more duckbills to replace every 3 years (I would guess the macerator system doesn't use them)

RV service folks are MUCH more familiar with macerator toilets (at least one toilet in every bath and a half DP is a macerator model) than VacuFlush systems.

ETA the one downside is you'll use more water/fill the black tank faster with a macerator toilet.  Just something to consider if you boondock or frequently do W/E-only sites.
I've been rebuilding the vacuflush generator every 2 years (and sometimes sooner) when in a stable location, to prevent issues when traveling.  I replace duckbills and bellows as well.  With 2 of us full timing, there is a lot of usage. 

Dometic Masterflush 8700 series macerator toilet has a water reducing usage feature that allow the toilet not refilling water after flushing (mainly for boaters in heavy waves).  It will still use more water than vacuflush, but less than normal mode. 

Re: Macerator toilet system to replace entire vacuflush system

Reply #3 –
Pics of inside layout.  The fan control will have to move up, to make room for macerator status display or flush contoller.  Easy access for wiring.

The toilet and hamper are on outside wall, drivers side.

Re: Macerator toilet system to replace entire vacuflush system

Reply #4 –
Dan, where are your grey and black tanks located in your coach?  Just wondering why FOT set up this type in your coach!

Re: Macerator toilet system to replace entire vacuflush system

Reply #5 –
Basement
Quote from: juicesqueezer –
Dan, where are your grey and black tanks located in your coach?  Just wondering why FOT set up this type in your coach!

Not a direct drop.  Hard to visualize inside the coach, but seems black tank is further back than toilet.  Plumbing runs are mostly hidden.

Black and grey are behind rearmost basement door, by the water manifold when viewed from passenger side, and behind drivers side rear dump valves.  40' tag axle coach.

Toilet discharges to rear of toilet, not downward.

I'll post some pics of basement plumbing when I can get file types to work.

Re: Macerator toilet system to replace entire vacuflush system

Reply #6 –
In the pic of basement vacuflush generator, the black pipe from the vacuflush is the one that dumps into the black tank.

The white flexible one is the one feeding from the toilet.  Above the black and grey tanks the white flexible hose connects to black rigid piping. 

Re: Macerator toilet system to replace entire vacuflush system

Reply #7 –
Quote from: AC7880 –
In the pic of basement vacuflush generator, the black pipe from the vacuflush is the one that dumps into the black tank.

The white flexible one is the one feeding from the toilet.  Above the black and grey tanks the white flexible hose connects to black rigid piping. 
There is little space and little access above the sewage  tanks (behind the water manifold cover) to merge the two black rigid pipes (feed and discharge). 

Seems easiest to retain the white flexible hose and modify the black dump pipe above the vacum generator to make a turn and then attach flexible hose to it.  I would hire a plumber to make that change.

Re: Macerator toilet system to replace entire vacuflush system

Reply #8 –
Quote from: juicesqueezer –
Dan, where are your grey and black tanks located in your coach?  Just wondering why FOT set up this type in your coach!


6106 is a custom floorplan.  It's a little AGDS, a little PBDS, and a little WTFS...  The couple who designed it did an amazing job IMHO.

Re: Macerator toilet system to replace entire vacuflush system

Reply #9 –
More investigation on possibly installing Macerator  8700 series Masterflush toilet and removing vacu flush toilet and the vacum generator in the basement.

Both toilets use a 1/2" npt fresh water feed from the rear.  Both use a 1.5" discharge to the rear.  Current vacuflush has 12 gauge wiring which the masterflush requires.  And in the basment, that 12 gauge feed already has 20 amp breaker.  So that makes things simpler all around.

I'm suprised Foretravel used a 20 amp and a 12 gauge wire as the vacuflush requires only 8 amps, but it sure makes the feasibility easier.

Next thing to figure out is the black tank full monitoring that shuts down the vacuflush when tank is full.  The macerator toilet also has recommended (but optional) full tank monitoring/auto shutdown. 

What are the odds the full tank system on the Masterflush will be compatible with existing wiring/sensor?  (probably low).

Tecma macerator toilets need 8 to 10 gauge wiring (depending on length of wiring run)  and 40 amp at 12 volt.  That is why I am not looking at Tecma.

Re: Macerator toilet system to replace entire vacuflush system

Reply #10 –
Drawback as Michelle pointed out is water useage.

 Vacuflush uses .27 gallon in normal mode, and .08 in low mode.

Masterflush use .85 gal normal, .45 gallon low mode.

We rarely dry camp these days, but do use some campgrounds with no sewer drop on site, but with a dump station.

If wanting spare Masterflush parts on hand in case of issues:
 macerator motor $413 to $489
water valve $41 to $106
control module $apprx $706

Expensive to have variety of spares on board.



Re: Macerator toilet system to replace entire vacuflush system

Reply #11 –
If I do this in stages, and do the macerator toilet inside the bathroom first, I wonder if the vacum generator in the basement would work in combination with the macerator toilet with no issues?

Then I could schedule a plumber for the piping change in the basement a week or two later.  I can easily remove the vacumn generator (pump) myself, but need a pro for the piping modification.

We are full timers and can only have the toilet system down during daylight hours only and only one day at a time.

Re: Macerator toilet system to replace entire vacuflush system

Reply #12 –
Updates?

Re: Macerator toilet system to replace entire vacuflush system

Reply #13 –
Too bad these Coach manufacturers have to make flushing a commode complicated. Our Prevost had the Headhunter system. Uses a ton of water and extra plumbing to route everything from toilet to black tank. If black tank was a direct drop, I would have put in a Dometic 320 - like we did in the Foretravel- which is a direct drop to the black. All manual- no electricity required.

Re: Macerator toilet system to replace entire vacuflush system

Reply #14 –
Quote from: Peter –
Updates?

Project on hold other than investigating how to potentially do it.  Other items (relocating our home base) have taken priority. Our homebase now is a Escapees co-op in Sutherlin Oregon, new homebase will be a Escapees co-op in Benson AZ.

 Also changing hydraulic engine cooling fans from electronic control to wax control is being considered, and higher priority if I proceed on it. 

I have a complete rebuild kit on hand I bought last year for the basement vacumn system, so I can rebuild in the interim if necessary.  I may do that in the next month or two to buy more time for potential conversion t macerator toilet.

My son in law in OK is a licensed plumber. I will have him take a look at plumbing routing in the basement sometime this fall.  Not asking him to do the work, just give advice. 

Re: Macerator toilet system to replace entire vacuflush system

Reply #15 –
Quote from: erniee –
If black tank was a direct drop, I would have put in a Dometic 320 - like we did in the Foretravel- which is a direct drop to the black. All manual- no electricity required.

I would do the same if direct drop.

Re: Macerator toilet system to replace entire vacuflush system

Reply #16 –
Dan, I changed the 01 U320 to the wax control and it worked fine.  My engine temp was usually 186 F  with a high of 195 powering up rolling hills and then back down to 186.

Re: Macerator toilet system to replace entire vacuflush system

Reply #17 –
Dan, I would not be too concerned with water issues with the macerator system.  We have installed a bidet in our coach and water usage is pretty high with this one, since it cleans itself before use and after.  Not an issue for us, remember, water is your friend when it comes to black tanks and issues.  Right now, I don't dump any more than before and we sometimes boondock or in a park with only W/E, plus we use the washer/dryer at least 3 times a week.  Having done plumbing work over the years, not licensed, but not afraid to take on just about anything with regards to plumbing, I went in and completely changed out my wet bay configuration on how FOT did theirs.  Works so much better!

Re: Macerator toilet system to replace entire vacuflush system

Reply #18 –
Juicesqueezer
Do you have pics of your wet bay alterations?

Re: Macerator toilet system to replace entire vacuflush system

Reply #19 –
Quote from: Peter –
Juicesqueezer
Do you have pics of your wet bay alterations?

I thought I had posted them once, but now have deleted those pics and I'm not tearing into the cover again to expose the inside.  Needless to say, I got tired of repairing the cables to the black and grey tanks and the weird setup with the 90's coming from those tanks, so went in and cut them all out and did a direct shot from black and grey out to the front of the bay.  I now have two gate valves out front and when I want to dump them both, I have a Y connector to allow this.  Not a difficult work around, but not for the faint of heart when it comes to doing the first cut!  Hope this helps!