Replacing sanitation line and wonder about the sizing required

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S41

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Aug 6, 2015
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US
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Currently boatless
I am in the planning stages of replacing all my sanitation hoses on our Symbol 41. I replaced the holding tank last fall after purchasing the boat. It was original to the 1986 boat. It was stainless with a few pin holes in the top. I replaced it with a plastic tank designed for holding sewer.

I don’t have any sanitation hose leaks, but a lot of fine cracks on the outside of the black hoses, especially where they bend. I am getting head order from some of these locations. Not horrible yet, but I am not waiting any longer.

We have two electric macerator heads with discharge lines that are 1” coming out of each one. One head uses fresh water and the other uses sea water. The fresh water head has a hose run of about 15 feet to the tank. This is the line that needs to be replaced. But, while I am at it, they are all getting done.

At this point, both 1” lines go about 5 feet then hook up to a lockable Y valve to allow direct over board discharge. I plan on removing the Y valves and run the lines directly to the tank on both heads. The boat has an overboard discharge pump from the tank that may get used someday that discharges overboard. In all my years of boat ownership, the holding tank has always been pumped to shore. But, down the road while cruising, I know this won’t always be the case.

On my aft head, the 1” discharge line connects directly to the Y valve through a 1” X 1 ½”reducer. The forward head has a reducer in line about 2 feet before it gets to the Y valve.

I am wondering if by removing the Y valves if I should be running new 1 ½” line to the tanks from each head or if I can run new 1” lines all the way from the heads and put the reducer just before the tank inlet? This would be a LOT easier to run the hoses and wouldn’t hold as much sewer in the lines if they don’t get pumped clean every time.

Except for three locations this is a pretty straight forward job on this boat.
Any thoughts from those that have done this job before? Will I be creating an issue using the smaller diameter hose?

Thanks!
 
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Bigger hose is better IMO. But you could certainly just reduce it towards the end of the run. And/or where it's the easiest to get at in the event of a clog.
 
This is one case where bigger may not be better. A smaller diameter means higher velocity which will keep it cleaner and leave less volume behind. Since it has already been macerated, 1" all the way should work fine.


David
 
In many parts of the world direct overboard discharge is the norm. You may want to hold on removing the y valves until you decide where you are going to cruise.
 
I reconfigured our OA 44 with down hill runs for both heads. No low spots in any lines. A riser pipe/hose directly after the head discharge (and hidden behind/under the adjacent counter) achieves the necessary elevation and also serves to keep clean fresh water in the bowls (concurrent fresh water conversion). Most Taiwan boats have enough space behind head and stateroom cabinetry to do this. Y valves moved under the vanities are located directly under the discharge of the vented loops. Valves accessed via a drawer in each cabinet. 1.5" lines for a largely gravity powered system. Reduced power consumption. No sewage stink from the system....ever.
 
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I don’t have any sanitation hose leaks, but a lot of fine cracks on the outside of the black hoses, especially where they bend. I am getting head order from some of these locations. Not horrible yet, but I am not waiting any longer.

10 years is about the average working life of ANY hose, so it's definitely time to replace your hoses...although I suspect that at least some of the damage to the outsides of radii in bends was done by heating the hose to make it bend tighter than it wanted to which stretched the "skin," weakening it enough to cause it to tear. If you'll have tight bends in your new hose, do NOT heat it to bend it...instead, break the hose and insert inline radius fittings...or go with a hose that DOES bend enough (more about hoses later).

We have two electric macerator heads with discharge lines that are 1” coming out of each one.

Sounds like you have Jabsco toilets....they're the only mfr who uses 1" discharge fittings. 1.5" is the standard size that every other toilet and tank mfr uses. So if you want to eliminate the reducing adapters, it would be a simple matter to replace the 1" discharge fittings on them with 1.5" fittings, available directly from Jabsco. Specify whether you need straight or 90 degree fittings, regardless of what you have now...'cuz all toilets ship with straight fittings when a 90 is what's really needed, which can make for some serious plumbing problems and leaks. Give Paul Campagna in tech support a call: 978-282-5246.

Whether to eliminate the y-valves and flush only into the tank depends on where you plan to cruise. If you're planning to do some ocean cruising, you'd certainly want the ability to flush directly overboard...but if you'll spend most of your time in US coastal waters inside the "3 mile limit," you can prob'ly do without the ability to flush directly overboard.

However, 15' is a very long run from the toilet to tank. About 6' is as far your toilets can move bowl contents in the time most people will keep their finger on a flush button without a lot of help from gravity...so unless it's downhill all the way, that could be a good reason to keep the y-valve in the discharge line, relocating it to a location that puts it higher than the top of the tank.

If your overboard discharge pump has been sitting unused for more than couple of years, it's prob'ly deteriorated to the point where it's unlikely to work. So depending upon how far "down the road" it will be before you can use it, either replace it or remove it altogether (it's easy to install one when you need one)
About hoses... this is NOT the place to skimp on price! Cheap hoses will permeate in a heartbeat. There are only two I recommend: Trident 101Trident Marine: Sanitation Hose is a double-walled rubber hose that's been on the market for about 20 years without a single reported odor permeation failure. It has only one drawback...it's as stiff as an ironing board, so not the best choice for a system that has a lot of bends tighter than very gradual sweeps. About 6 years ago Raritan introduced their SaniFlex hose Raritan Saniflex Hose ...flexible enough to make a U-turn. Pricy, but not single reported odor permeation failure either.

If you'd like a little one-on-one help in spec'ing out your plumbing runs, you're welcome to give me a shout...I'll be glad to help you.
 
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When I did mine ,I put in 1 1/2"PVC on the long straight run from the aft head. 1 " to a reducer1 " barbx1 1/2slip to PVC then another fitting 1 1/2 slipx1 1/2 barb on to a short hose then in to the tank. Saved on hose cost and PVC worked nicely.
 
If you're getting rid of those 1" Y valves I'd love to buy one I have searched high and low for them online.

Thanks
 
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