Water maker waste routing

[sanibel sailor]

I have almost completed the installation of a small watermaker and need to route the discharge/waste line. It is mounted in the cockpit locker. Several options, in order of my preference. I would be interested in other input.

1) Boat has drains on deck just inboard of the toerail. Fiberglass tube with an elbow just below deck level. Tees into the cockpit drain then to a never-closed seacock. I could drill and tap the fiberglass tube and install a barbed hose fitting. It is close by, about one foot above the unit, keeps all the plumbing in one compartment and if I run the hose just under the deck, should not have issues with back flow from deck into the unit. First choice unless someone sees a problem I don't.

2) There is an unused (currently capped) Tee fitting on the galley sink drain. Was used as a icebox/shower sump drain. Galley is just forward of cockpit so it is fairly close, but routing is a little challenging. Also, the Tee is below the waterline. A bit of concern about galley wastewater co-mingling and standing in the brine discharge line. Also puts plumbing into another compartment. I may someday want to revive the shower/icebox sump plumbing and need that tee.

3) Less desireable is an old AC discharge just above waterline in the main cabin. After I got the boat, I replaced the old plastic thruhull fitting with bronze and a capped ball valve. It is available, but even further, more difficult hose routing and puts additional plumbing in main cabin lockers.

4) There was an old seacock for AC intake that I removed and glassed over. I could reinstall that. Another hole in boat, one more thing in an already cluttered area and would require a haul out. Last choice.

[Paul L]

Its nice to have the brine discharge above the waterline. This allows you to easily check on the operation of the system while its running. WM run for long hours, so an occasional check on the outflow is good.

[senormechanico]

The only disadvantage I can see with putting it into a sink drain fitting is the noise it might make.

[chuckr]

We put ours to the galley sink drain with a T - been working great for the past 10 years

[Sailmonkey]

Ours used to be routed to the cockpit drain. It caused no problems over the years.

If the brine enters the drain near the primary inlet you can see the flow usually, or even become tuned to the gentle gurgle the water makes.

[Polar Opposite]

I also use the galley sink drain, without a problem.

[a64pilot]

Anyone found a thru hull fitting that will fit a 1/4” plastic line?
I re-purposed the thru hull that was used for the old water cooled refrigerator, but have embarrassedly used tape to bush up the diameter of the watermaker hose, which is Mikey Mouse and I’d like to do it correctly.

[mitiempo]

Originally Posted by a64pilot

Anyone found a thru hull fitting that will fit a 1/4” plastic line?
I re-purposed the thru hull that was used for the old water cooled refrigerator, but have embarrassedly used tape to bush up the diameter of the watermaker hose, which is Mikey Mouse and I’d like to do it correctly.

Easy to find plumbing fittings in bronze that can reduce whatever size through hull valve to 1/4".

[belizesailor]

However you route it, you dont want back pressure at the brine discharge.

As others have said its convenient to have the brine discharge visible for troubleshooting.

[newhaul]

When I installed the 35 in my boat I used the now removed sewage holding tank vent line .well above waterline and vents are designed for 1/4 inch tubing.

https://www.wholesalemarine.com/perk...xoCwdgQAvD_BwE

[lamadriver]

Mine is Galley sink T drain with a ball valve. works great

[a64pilot]

Originally Posted by mitiempo

Easy to find plumbing fittings in bronze that can reduce whatever size through hull valve to 1/4".

You have a link? Although no valve, it’s well above water line so just a plastic thru hull.

[a64pilot]

Originally Posted by newhaul

When I installed the 35 in my boat I used the now removed sewage holding tank vent line .well above waterline and vents are designed for 1/4 inch tubing.



https://www.wholesalemarine.com/perk...xoCwdgQAvD_BwE

That one is 5/8”?

[Tellie]

Originally Posted by a64pilot

Anyone found a thru hull fitting that will fit a 1/4” plastic line?
I re-purposed the thru hull that was used for the old water cooled refrigerator, but have embarrassedly used tape to bush up the diameter of the watermaker hose, which is Mikey Mouse and I’d like to do it correctly.

That might be a tough one to find. What size is the watermaker hose (1/4" for a brine discharge??) and what size is the thru hull, and what type of connection is the thru hull use?

[newhaul]

Originally Posted by a64pilot

That one is 5/8”?

possibly yes I just did a quick Google for the general unit I didn't look at the specifics of this exact one .
Here is a 5/16 barb fitting that 1/4 hose will fit on . Soak the end of the nose in hot water for a minute before putting it on the fitting .
https://www.holley.com/products/fuel...s/parts/19-174

Are you sure your overflow is 1/4 inch ?

That sounds more like the product water on my 35.