Marine vs RV toilet

[Mako]

My toilet is located directly above the bblackwater tank, which offers the opportunity to use an RV toilet which directly discharges into the holding tank.

What pros and cons would there be to an RV unit versus a marine toilet with manual pump? Is there the possibility of smells coming up through the RV unit?

It would seem that they both use about the same amount of water, cost the same but the marine unit has more parts to maintain and get clogged.

Some feedback please.

 

[hollywood8118]

My toilet is located directly above the bblackwater tank, which offers the opportunity to use an RV toilet which directly discharges into the holding tank.

What pros and cons would there be to an RV unit versus a marine toilet with manual pump? Is there the possibility of smells coming up through the RV unit?

It would seem that they both use about the same amount of water, cost the same but the marine unit has more parts to maintain and get clogged.

Some feedback please.

If you can directly down into the holding tank you are the envy of most of us with marine heads.. We had that setup on Volunteer and I REALLY miss it.. dead reliable. Mine was very similar to a vacuflush with the big ball valve. You will need a good macerator as the waste isn't reduced in size by the toilets macerator and it will need to deal with larger "solids".

The smell if the tank is vented right should not be a issue.

HOLLYWOOD

 

[FF]

The RV toilet has 100% of the advantages, the boat "marine toilet , 0%

The water use per flush is 1/4 to 1/20 or less than a marine toilet , so the holding tank lasts longer.

The lack of a sea water pump (it uses a cup of fresh water) means no rebuild kits , no thru hull to service.

No stench of dieing stuff from the sea water.

Dropping straight down means no expensive hose to replace when the hose starts to stink.

RV is very simple so does not require a Guest briefing or demo.

As its RV the part to rebuild it are cheap and readily available.

Carry a spare for every decade of use.

AS on all things there are Quality units and cheapo units , a tall Sealand with white china bowl might be a choice.

Tall because even in a very rough seaway most guys think their aim is perfect.

 

[Donsan]

AS on all things there are Quality units and cheapo units , a tall Sealand with white china bowl might be a choice.

Tall because even in a very rough seaway most guys think their aim is perfect.

I always take my aim into a wide mouth plastic coffee can and then either dump it in the toilet or dump it over board. It is hard to miss.

 

[psneeld]

The RV toilet has 100% of the advantages, the boat "marine toilet , 0%

The water use per flush is 1/4 to 1/20 or less than a marine toilet , so the holding tank lasts longer.

The lack of a sea water pump (it uses a cup of fresh water) means no rebuild kits , no thru hull to service.

No stench of dieing stuff from the sea water.

Dropping straight down means no expensive hose to replace when the hose starts to stink.

RV is very simple so does not require a Guest briefing or demo.

As its RV the part to rebuild it are cheap and readily available.

Carry a spare for every decade of use.

AS on all things there are Quality units and cheapo units , a tall Sealand with white china bowl might be a choice.

Tall because even in a very rough seaway most guys think their aim is perfect.

Went that way and smiling ...

 

[FF]

"Went that way and smiling ."..

For how many years, ?

 

[psneeld]

I converted both my heads to electric as soon as I bought the boat 4 years ago.

One to an RV toilet as I had a good drop and access in the bilge to create a mini holding tank that gets macerator pumped to the big one whenever.

The other one I saved the bowl as it was good enough for now so to speak....and will switch to an RV type if I get around to it in my lifetime.

Both are nice in the fact that the macerator are stock and can be swapped in minutes without hugging a toilet. The may also both be upgraded to just a gupler type in the future now that I have an Electroscan system.

 

[meridian]

On a previous trawler had an RV unit on top of a 50 gallon holding tank. No odors no problems. It was easy to use a high pressure hose to give a final cleaning to the tank.

 

[funangler]

I use an RV style toilet over a 55 gallon tank. The system is very trouble free as long as you have a large air vent into the tank. The toilet drops the fluid into the tank so fast you need the air to exit through the vent or it will burp in the bowl on the flush. I had 5/8 inch vent that was not large enough. I add a 1.5 inch vent to the tank and no tank gases come up on flushing.

 

[hmason]

I have 2 Vacuflush heads feeding 2 separate holding tanks. Each tank can be pumped overboard with separate Sealand diaphragm pumps, or sucked out through a deck fitting. Am I correct that there is no macerator pump? Does the suction of the vacuum system "disassemble" the solid waste?

 

[Mako]

I add a 1.5 inch vent to the tank and no tank gases come up on flushing.

That seems like a very large hole to have in the hull, perhaps seawater could wash into the tank during heavy seas.

How far above the waterline does your vent exit the hull and is it towards the bow/midsection/stern? If you could do it again do you think that a 1" vent would have been sufficient?

 

[funangler]

I have the through hull 18 inches off the water and a loop that is about 3 ft off the water. The outlet is mid ship and never seem to have water intruding into the tank. If it was that rough I want the tank full anyways to lower my center of gravity and reduce the weight shift. The condition would be like waves greater that 10ft with a short interval. The 1 inch fitting would most likely be fine if the run was short. I had the 1.5 in hose and fitting already.

 

[FF]

With an RV setup , watching waste drip out the vent line is NOT how one knows the tank is full.

The waste level can simply be see at a glance or one could wait till its so full the toilet will not flush.

Therefore there is no need for a thru hull fitting for the vent , it can simply be lead to the cabin top to vent.

The amount of rain that might get in the open vent is minor , though a U shaped vent could be used.

1 1/2 or 2 inch is the most common size , as RV dump with a 3 inch outflow , to speed up the process.

RV will have grey water in the waste tank also , do there can be lots to dump.

 

[hollywood8118]

With an RV setup , watching waste drip out the vent line is NOT how one knows the tank is full.

The waste level can simply be see at a glance or one could wait till its so full the toilet will not flush.

Therefore there is no need for a thru hull fitting for the vent , it can simply be lead to the cabin top to vent.

The amount of rain that might get in the open vent is minor , though a U shaped vent could be used.

1 1/2 or 2 inch is the most common size , as RV dump with a 3 inch outflow , to speed up the process.

RV will have grey water in the waste tank also , do there can be lots to dump.

my setup in Volunteer was similar to this, but I believe it was a 1" vent. It went all the way up the inside of the mast and exited at the top.. plenty high enough to get the stink away. A really great setup.
HOLLYWOOD

 

[Capt.Bill11]

i always take my aim into a wide mouth plastic coffee can and then either dump it in the toilet or dump it over board. It is hard to miss.

That perhaps is perhaps TMI :d

 

[Capt.Bill11]

That seems like a very large hole to have in the hull, perhaps seawater could wash into the tank during heavy seas.

How far above the waterline does your vent exit the hull and is it towards the bow/midsection/stern? If you could do it again do you think that a 1" vent would have been sufficient?

At least one, or better off two vent lines that size, one on each side of the hull on two sides of the tank makes for a great system to promote good air flow to keep the good bacteria happy in your holding take.

Sea water getting into them is a nonissue if properly placed.

 

[funangler]

I placed mine out the side of the hull did not want to smell it up top. I also have the old 5/8 inch vent on the other side of the boat. You will get smell when the holding tank chemical get old. I tried bubbling the tank just got tired of listening to the motor and bubbles.