Best wastewater hose to use

[GordMay]

Dometic’s (SeaLand) new (Italian made)? OdorSafe Plus hose is claimed to deliver 20% more resistance to odor permeation compared to the previous OdorSafe brand hose.
http://www.vacustat.com/pdf/OdorSafe%20Plus%20NR.pdf
Hose / Fittings
http://www.cruisersforum.com/forums/...-bay-4515.html

[Triton318]

Originally Posted by drh1965

Both vented loops will be mounted on the bulkhead above the head.

Seven years ago, when rebuilding my Triton, I installed a Blake Lavac marine toilet with an intake hose and a hose that goes from the toilet to the diaphragm pump and then to the discharge through-hull/seacock. I never installed vented loop fittings for either the intake or discharge side (partly because its function seemed to elude me and partly because the fittings were so expensive). Each hose does, however, have a loop that is situated above the waterline. Still...I often wonder if something catastrophic is going to happen because I don't have the vented loop fittings. To date, I've never had a problem with water coming in when it shouldn't. (Also, I always close both seacocks when I leave the boat.)

[rebel heart]

Originally Posted by Triton318

Seven years ago, when rebuilding my Triton, I installed a Blake Lavac marine toilet with an intake hose and a hose that goes from the toilet to the diaphragm pump and then to the discharge through-hull/seacock. I never installed vented loop fittings for either the intake or discharge side (partly because its function seemed to elude me and partly because the fittings were so expensive). Each hose does, however, have a loop that is situated above the waterline. Still...I often wonder if something catastrophic is going to happen because I don't have the vented loop fittings. To date, I've never had a problem with water coming in when it shouldn't. (Also, I always close both seacocks when I leave the boat.)

I did the same thing a few months ago: Lavac went in, and no vented loop if you're discharging overboard. I'm going to go back through and clear that out however. It hasn't caused me any problems either, but then again I haven't needed to use my seat belt yet either.

[drh1965]

You guys are playing with fire. On my boat, the PO's broker broke the joker valve in the "wet" Flush setting. He then left the scene. I came to check on the boat and found that the toilet had syphoned water out of the sea until the bowl was filled to the top and it was continously dripping around the seat. Had I not checked on the boat, the bilge pump might have flattened the batteries (glub glub glub goes the boat). Had the top of the head been below the water line, the boat would have likely sunk pretty fast.

If a vented loop had been installed well above the heeled water line, the syhon action would have been broken (assuming the vented loop was clean and functioning properly) even though the head was broken. The same exact principal applies to the output side of the head. You can end up with holding tank or sea water syphoning back through the head.

[cal40john]

Originally Posted by Triton318

Seven years ago, when rebuilding my Triton, I installed a Blake Lavac marine toilet with an intake hose and a hose that goes from the toilet to the diaphragm pump and then to the discharge through-hull/seacock. I never installed vented loop fittings for either the intake or discharge side (partly because its function seemed to elude me and partly because the fittings were so expensive). Each hose does, however, have a loop that is situated above the waterline. Still...I often wonder if something catastrophic is going to happen because I don't have the vented loop fittings. To date, I've never had a problem with water coming in when it shouldn't. (Also, I always close both seacocks when I leave the boat.)

It only matters if the top of your head is below the waterline at any time, any heel angle.

Loop a hose from a seacock to above the waterline and back down below the waterline in your boat. If you started with air in the hose when you open the seacock, nothing happens. If you suck on it so water is in the entire hose, now water will come into your boat. (Sorry if you were real clear on what a siphon was.) Now plug the end of that hose into your head that has had a few years of service such that the valves in it don't seal 100% and the water will continue to come in if the top of the bowl is below the waterline. If the top of your bowl is above the waterline, water will come in until it is level with the water outside the boat. Actually you have no valves on the intake side of your Lavac, so either your head is above the waterline, or you have an air leak in the intake hose that you aren't aware of. Are you sure you didn't install the air bleed valve that comes with the head? The air bleed valve is an anti-siphon break. Any sort of hole in the hose near the top of the loop will allow air into the hose breaking the siphon. A more complicated siphon break has a one way valve that when the water in the hose is under pressure the valve closes to prevent contents of the hose from coming out. When the contents are trying to siphon into the boat the pressure in the hose at the top of the loop is less than surrounding, the valve will open allowing air in and breaking the siphon.

http://www.blakes-lavac-taylors.co.uk/pdf/lavac.pdf

If you do have the air bleed in the intake hose, and therefore there is a possibility that your head is below the waterline, and the check valves in your diaphragm pump leak and you somehow leave the outlet hose full of water, then you will benefit from an anti-siphon valve in your outlet hose.

Many years ago on a trip from Hawaii to Seattle, the boat I was crewing on had a Lavac head. On the tack that put the head on the high side of the boat, normal pumping action did not produce enough vacuum to lift the water to the top of the loop. The air bleed let air in too fast. We resorted to bringing pots of water from the galley to pour into the head. One day I planted my feet in the corners of the room, my back against the bulkhead and pumped as fast as I could. Once I got the water around the corner (over the top of the loop), I got water to flow into the head.

John

[LifesAnAdventure]

As a general contractor of 25 years and a sailor for 40 years I would lean towards using tubing over pvc of any wall size. I am actually in the process of changing my head and hoses to my holding tank. I thought the odor was solely from the hoses but when I removed the holding tank from it's holding area I found that someone previous to me owning the boat had drilled a hole into the tank and I had odors as well as liquid and solids spewing into my bilge. I was pretty upset when I found this but thinkful I did. A hardware store owner on the island I keep my boat suggested using some silicone and a stainless steel screw to plug the hole in the poly tank. I did this just the other day and when I go back to the boat Wednesday I'll see how it looks. I will be placing my order for Trident Sani Shield Sanitation Hose #102. The best price I found was at Defender.

Has anyone found a better price any place other than Defender?

[janice142]

Defender is having their once per year, 4-day sale. It ends tonight at 2350.