Sanitation Lines

[Wayne162]

Does anybody know where one can purchase MDPE pipe in the United States? My story begins with a clogged head in the aft stateroom on my maiden voyage with the new boat from Myrtle Beach to Charleston, SC my home port. The fluid level would not go down. I donned the wet gear to clean out the nasty's the previous owners had left, and took the Crown head apart. The head appeared operationally fine with a need for some new gaskets and impeller, but they were not the immediate issue. I pumped out the rear holding tank and disconnected the sanitation line at the head. I ran a snake through it around a lot of calcification and got to a hard blockage at about 7' of a 10' run. I could not clear the problem.

While looking for a boat, I went on about four Carvers including the one I purchased. Every boat we went on had a smell that I have since been told is "Potty Boat". All of the owners and brokers advised that the boats had just been closed up for a while. I can air it out, but it never really leaves its just not as bad. I did have a local sanitation contractor come on board to let me know what he thought about the clog. After an hour long sales pitch he left with his price of $6000.00 to fix it.

I have since been reading alot and have decided to replace the sanitation lines to alleviate the clog and hopefully the odor. But it appears that the sanitation lines often fail and are pricey. I want to replace the current lines with Medium-density polyethylene (MDPE). It is flexible and impervious to permeation. My problem is, I cannot find it available in 1 1/2 ID near me. Any thoughts are appreciated.

[waybomb]

There are a few manufacturers of impermeable hose; some even guaranteed for life to not let odor through.
Search the net.

[Viper]

You can use rigid PVC where ever possible, especially anywhere that liquid or solids will always be in the line since it is impermeable. Where impractical to use rigid line, use one of the premium hoses on the market, they are more expensive but worth it in areas as mentioned above. I can't remember the manufacturer but there is a premium grey hose on the market that's supposed to be the best but Dometic's (SeaLand) OdorSafe is a very good hose too compared to others.

You may want to consider that the blockage you're running into may actually be a check valve in the line. Some OEMs use them and put them in the worst possible places for access.

[burceh]

Along these same lines, any idea what is causing my head to smell so bad after flushing that you have to vacate cabin?

[Wayne162]

Thanks for the replies. I don't think its a check valve issue as I have a clear straight line view of the sanitation hose to the holding tank. Its a solid straight sanitation hose. Burceh, check your joker valve. If its worn it will allow line odor back up to the head. Mine would not seal as it was calcified. Either replace or clean it and periodically run vinegar through the line prior to pump out to keep it clean.

[waybomb]

Along these same lines, any idea what is causing my head to smell so bad after flushing that you have to vacate cabin?

The water used to flush comes from your body of water. That body of water is full of organics. These organics love to grow and rot in the hose between the through hull and your head for weeks on end; a built in cesspool in your boat.

If you do not use on-board water storage, but have a tank, You might consider changing that tank over to supply flushing water to your head.

[burceh]

Thanks. I will look at joker valve but suspect that running fresh water to flush is the answer
.

[RGrew176]

My 3007 carries 93 gallons of water. There is a water line running from the port tank over to the starboard tank. It would be very easy for me to tap into and tee off that line so I could flush my head using the water from my freshwater tanks. Not drawing from the body of water I am in would in some ways be a plus especially since we have the algae problem every summer in Lake Erie and it does stink at times.

If I were to tap into my onboard water system would a straight tee work or would I and should I utilize some sort of check valve in the line to keep water from back flushing into my onboard water line. Water back flushing into the water line would be a concern.

What say the experts here.

[waybomb]

I am no expert, but definitely a check valve, but I also believe the fresh potable should be completely isolated from the waste system.

Even though water won't back flow through a functioning check valve, I would guess microscopic pathogens could migrate across a check valve quite readily.

I've had salmonella poisoning, I am guessing from restaurant food, and was in the hospital for 2 weeks, almost died. I take no chances anymore.

[RGrew176]

I am no expert, but definitely a check valve, but I also believe the fresh potable should be completely isolated from the waste system.

Even though water won't back flow through a functioning check valve, I would guess microscopic pathogens could migrate across a check valve quite readily.

I've had salmonella poisoning, I am guessing from restaurant food, and was in the hospital for 2 weeks, almost died. I take no chances anymore.

That would be my concern too which is why I am only considering it. The potential of any backflow into the fresh water tank is a concern.