Drain and Intake on one Thru Hull ?

[unbusted67]

I just installed a composting head and want to glass in my sewage thru hull and my salt water intake for the toilet. I had a salt water wash down t-ing off of the intake for the toilet that I will no longer be able to use.

My question is this: can I T my salt water wash down into the thru hull that we use for our bathroom sink drain? It is just a salt water wash down so if the first few seconds of spray come up as grey water its not the end of the world. Is this even possible?

[daddle]

You can try it. Keep the Tee low. Might suck air thru the drain.

[David M]

No, you never want to connect your sanitation system to any other system in any way. This is for health reasons and smell reasons. Given the right conditions, fluids can flow the wrong way through a hose or pipe. The same applies to your gray water system, potable water system, engine cooling system and your seawater washdown system. All should be isolated from one another so that there is no possibility that one can contaminate the other.

Also, never assume you can get away with it by using a check valve. Check valves can and do fail.

I agree with what Daddle says about the possibility of sucking air.

[Sailmonkey]

Our salt washdown is teed to the head sink drain, no problems, I just need to clean the strainer for the pump more often than if it wasn't this way. It occasionally sucks air, but never for more than a 1/2 second or so.
BTW, if you shave the morning that you raise the anchor you'll need to clean the pump strainer!!

[Cheechako]

Why change it? I've found gurgling in the sink and not a steady flow the one time I tried it.

[Kettlewell]

I don't see why it wouldn't work. I'd suggest just leaving the old through hulls in place and capping them off rather than glassing them in. You or someone in the future might want to use those through hulls again. I've got a composting head and I've just capped off the through hulls. I was thinking I might use the old intake one for a wash down pump some day. Or I might install a seawater intake for a fridge cooling system some day.