Convert Lavac to Fresh water flushing?

[SV Demeter]

Has anyone done this? New boat has a lavac and I like it but I’ve been spoiled with freshwater vacuflush heads from my prior boat. Seems like it should be pretty doable as there is a foot pump for fresh water in the same head. Maybe just T into that line and use a check valve?

[northwestsailor]

Hi Ted

We have two Lavacs each with both manual and electric pumps in series as per manufacturers specs. What is nice about that electric pump is that it keeps pumping after the waste has been flushed out such the pipes get cleaned out pretty well. Of course if you leave the boat for entended periods that’s when you might want a fresh water rinse. We also do a vinegar rinse before leaving. Just some thoughts.

[peghall]

Not a good idea 'cuz toilets that are designed to use fresh water need pressurized water, siphon breaks and backflow preventers to protect the potable water supply...none of which you have with the Lavac and just a foot pump for fresh water.

But if you're willing to add an electric water pump, there is ONE--the ONLY one--manual marine toilet that uses onboard pressurized flush water: the Raritan "Fresh Head" FRESH_HEAD Promo Sheet and it's even simpler to use than your V/F was. This retailer has it for the best price Raritan Fresh Head @ Boatersland (note that the box on that page is a menu). Unfortunately the "conversion" or "retrofit kit" won't work with the Lavac.

--Peggie

[nwdiver]

If you have lots of FW, setup an isolated ( separate) FW tank for the heads, then pump in FW not seawater.

[Freedom45]

I my old boat I set the Lavics up with fresh water flush.
Used a small Dedicated tank that auto refilled and y valves to switch back to sea water. Worked very well.
Lavics do not use pressure water.

[peghall]

A separate flush water tank is one solution, but USCG regs require that it be completely separate from the boat's fresh water system--no common plumbing, not even the vent or fill. So while it's ok to be able to switch between fresh from the tank and sea water, being able to auto-fill from the boat's fresh water tank isn't.

If you want to flush using fresh water, rerouting the intake line to tee into the head sink drain line is a better idea. Tee needs to be below waterline to allow flushing with sea water. To rinse the sea water out of the entire system, close the seacock and fill the sink with clean fresh water...flush he toilet. Because the seacock is closed the toilet will pull the water out of the sink...rinsing out the intake line, pump, channel in the rim of the bowl AND the discharge line. Works quite well with "regular" marine toilets, manual and electric...I see no reason why it wouldn't work just as well with a Lavac.

--Peggie

[blubaju]

Originally Posted by peghall

Not a good idea 'cuz toilets that are designed to use fresh water need pressurized water, siphon breaks and backflow preventers to protect the potable water supply...none of which you have with the Lavac and just a foot pump for fresh water.

But if you're willing to add an electric water pump, there is ONE--the ONLY one--manual marine toilet that uses onboard pressurized flush water: the Raritan "Fresh Head" FRESH_HEAD Promo Sheet and it's even simpler to use than your V/F was. This retailer has it for the best price Raritan Fresh Head @ Boatersland (note that the box on that page is a menu). Unfortunately the "conversion" or "retrofit kit" won't work with the Lavac.

--Peggie

All I would add is a small intermediate freshwater tank, then plug in the suction of the lavac there. Only reason, by all means, you want to separate toilet waste from your fresh water system. Yacht stuff isn't reliable at all. Fill manually or mechanical or electrical float switch with solenoid

But I'd never change my lavac to drinking water, far to precious on sea. In Marina's we use the shower head and do not close the lid when pumping

Yes, educating guests & crew not to stop pumping when the last brown water disappeared is a cumbersome task. Still I'd never change my Lavac style toilets (2 homemade in carbon and build flush in the bench)

[nwdiver]

Use a separate removable hose to fill FW flush header tank so the tank is isolated from FW system.......the one I know of is 35 gal which gives several weeks of FW for the head.....I thought it was much simpler than pressure water and all the back flush valves used in most FW systems......I think it was on a Lavac head because it had the big whaler pump mounted on the wall of the head......

[carlosproa]

I am not offering a solution but maybe something to think about.
The sink in the head doubles as a handheld pressure shower. To keep the bowl fresh in between uses, we simply use the hose and spray the toilet bowl to rinse it with fresh water.
No contamination issues