• Welcome to this website/forum for people interested in the Morgan 38 Sailboat. Many of our members are 'owners' of Morgan 38s, but you don't need to be an owner to Register/Join.

Water Tank Switching Valves Under Galley Sink

mpearson

Mark Pearson
Staff member
We are going to be re-plumbing the pipes/valves under the galley sink with PEX this winter. And proactively replacing our ancient but still functional water heater at the same time. There are a bunch of slow leaks in the old grey polybutylene and hose clamped patchwork, so we can't ever just leave our water pump on. I think we will be replacing the longer runs to the head and the tanks some point in the future too.

There are several good threads on this forum wherein people describe their experiences doing the same.

But I'm am wondering about those valves which are used to switch between the two water tanks:
Has anyone ever re-done those so that they are in a more accessible location?

It would be nice not to need to dig out the stuff under the sink and crawl around & do boat yoga to reach and open/close those valves.

Like I'm thinking about putting the valve stems someplace where they are accessible from the outside. Like on the starboard sink cabinet face? Or countertop? Or the forward facing face of the sink cabinet? It would be recessed, of course, so I wouldn't tear skin on it when I am thrashing about.

I was considering a three-way motorized valve, that could be operated with a switch, but that might be a little too decadent.

I like the manifold approach that others have used, and I think I'll do that.

Can anyone think of a reason not to plumb in a watermaker feed so that it backfills the tanks from there? I could put a check valve before the pump so that it would all be very low (or no) pressure.

Any advice is appreciated.
Thanks,
-Mark
 
Last edited:

Warren Holybee

Active Member
You could almost leave them where they are and put a cabinet door on the front of the cabinet behind the cushion. That would be fairly easy. I have not considered moving them. They suck to get to, but I can reach them blindfolded with only a little yoga.

I am not an expert on watermakers, but I would plumb into that manifold. I foresee a way to have the water go out the hand pump tap while starting up and testing quality, then opening the tanks when it is good. I think it would be a clean and convenient system.
 

mpearson

Mark Pearson
Staff member
Warren - yeah, that's a good idea: a little hatch or cabinet door on the front of the cabinet. They could then stay generally where they are right now.

And yeah, on the watermaker, that's what I was thinking, too: using the hand pump tap for testing, then switching to the tanks.
 

terry_thatcher

Terence Thatcher
Mark, you should come by and look at my water maker arrangement. It isn’t quite as convenient as you may want, but it works and might give you ideas. By I the way, the feed line off the WM is very small and you also need to plumb in a flushing line from the man water system.
 

mpearson

Mark Pearson
Staff member
Terry - thanks, I for sure want to come look at Adavida before I pull the trigger on anything.

Warren - I crawled all around taking things apart and doing measurements. I really like the idea of the hatch on the front of the galley sink cabinet. I’ve got it all measured and I’m going to do it. Great access to valves for switching tanks, the water filter before the pump, and (bonus) the air switches for our bilge pumps. It’ll usually be hidden behind the cushion.

I’m going to do some valve trickery to avoid a situation where the watermaker feed is acidently valved off (feed to starboard & v-berth tanks). I could easily accidently have both tank valves closed. Turns out if the feed gets over 5 PSI (about 10 ft of head), it can permanently damage the watermaker membrane. I’m thinking a 3-way ball valve, so one of the 2 tanks is always being fed. If the tank is full, hopefully the vent line will release the pressure.
 

mpearson

Mark Pearson
Staff member
After more reading, it sounds like Spectra wants a little 1/4" end product tube to go into the top of each tank. With zero chance of back pressure. So I think I'll keep the watermaker product line separate and probably not under the galley sink at all.
 

terry_thatcher

Terence Thatcher
I put my 1/4” tube into the port tank fill hose. I have a valve that allows me to join my port and starboard tanks. My flushing line comes from the main post-pump line under the sink. Easy to get to and open.
 

PROFLO PF1010SSAD PROFLO PF1010 10 X 10 Metal Universal Access Door​

I'm a sucker for stainless steel. I cut this one in for access to faucets and valves.
When the bunk board cushion is up its out of sight.
Life made easier with an oscillating plunge saw!
 

mpearson

Mark Pearson
Staff member
John - thanks for that tip. I'm biased toward stainless steel as well. I was going to have BoatOutfitters.com fabricate an access door, but in order for it to be almost flush, it would have an aluminium frame. I like the SS option better. And this ends up being less expensive too.
 
Top