My wife and I own a 2019
Lagoon 42, Ocean Song. She is a 3-cabin owners version with three
salt water,
electric heads. All three heads have commoderizers, in-line chlorine treatment. The commoderizers
work great and we have yet to have any foul odors or calcium build up in our hoses.
We are thinking about
plumbing the heads so that we have the option of either
salt water or fresh
water flush. The reason is that in certain areas the
raw water can be pretty dirty. Just as there are places we don't run the
water maker, there are places I don't want the
raw water in our
toilet bowls. In some
marinas for example we see
water we don't want in our
toilet bowls and occasionally in an anchorage there can be enough run off after a heavy rain for the water to be quite murky.
We'd like to have the option of going to a fresh water flush temporarily. If the raw water isn't dirty the commoderizers make the
salt water flush perfectly fine. We will continue to use
salt water as our primary option to conserve fresh water. We are capable of producing our own fresh water, but we still try to conserve when possible.
I would like to solicit ideas about a good setup. On the fresh water side we have seen conversions with solenoid and anti syphon valves, with the solenoid wired in to the
electric head's dedicated (salt water)
pump. We will likely include check valves as a backup to the all-in-one solenoid and anti-syphon valves as extra protection for our fresh water supply. A conversion from salt to fresh water flush seems relatively straight forward but there are a couple of questions that arise if we want to keep the salt water flush option available. Any
advice is welcomed and if my assumptions are wrong, let me know. I also know there's more than one way to do it, but I'm looking for a well-tested way.
The Basics:
1) We would "T" into the ship's fresh water supply under the sink in the
head,
route the fresh water into and through the solenoid and anti-syphon valve, then into a ball valve.
2) On many conversions with electric heads, the salt water line into the
head is simply capped off. The solenoid is wired into the salt
water pump so that it's activated when the head is flushed. I assume I can place the ball valve between the
pump and head,
route the salt water line into the same ball valve mentioned above and that would allow us to switch between fresh water and salt water flush.
3) It seems that we need to keep our
thru hull open supplying salt water to the head's
electric pump so that it doesn't burn out. Since I've seen installations (on YouTube - Out Chasing Stars) that simply cap off the salt water line, a closed ball valve should
work.
4) My hope is that we can design a system, that once installed, with the turn of a couple of valves we can switch between water sources. Although we don't want to waste
money, we don't mind spending a couple of hundred dollars per head to make it right. We plan to
live aboard for several years.