Auto-Fill on fresh water tanks?

[Andiamo2018]

I keep thinking there should be an easy way to keep our fresh water tanks full. We are on the boat a lot and enjoy the shower, washing dishes, rinsing fruit etc. As we also use the boat frequently I'm not worried about the water in the tanks sitting - it will get used up often.

But while sitting at the dock we would like to keep our tanks full! For lots of reasons (we are in an earthquake zone after all) I would like to figure out how to have those tanks fill automatically.

My best idea so far has been to set up a connection to city water with a T valve (with a restricter) so we can just reach under the galley sink, turn a ball valve lever and let the tanks fill until water comes out the air vents. Then we can turn the handle the other way and have the city water go straight into our boat for use.

I also enjoy leaving for trips at the spur of the moment and it is great to just disconnect and go with little fanfare.

I've also read a LOT about the debates of connecting to city water etc and I'm totally comfortable with it (gallon meter, sediment filter, ball valve outside at the end of the finger where it is easy to remember to turn it off when we leave, and a large enough bilge pump that can keep up with city water).

Ideas?

Not sure if this exists but I can imagine a fresh water fill cap that integrates a hose connection on one side (um, the outside and a float switch on the other side. This would only work if the air vents are higher than the fill hole, or at least higher than the float switch which could possibly be in a flexible hose...our fill hose goes straight down far enough for this to work btw.

 

[O C Diver]

Why not just top the tanks off before you leave the boat to go home?

Ted

 

[tiltrider1]

I have done this several ways on different boats. I start by connecting a 12v sprinkler valve to the end of a garden hose. Then I connect the garden hose to the tank fill. I then run the 12v wires through the old telephone sockets that most boats still have. Now if you have a TankWatch or a Gobius you can connect direct to these and they will auto fill from 1/4 tank to 3/4 tank. If not you can install a 120v light or fan timer. Don’t worry that they are 120v, they are just a timer switch and they are more than capable of handeling this 12v circuit. Now all you do is twist the timer and let it fill for a given amount of time.

I don’t like systems that can fail in the on mode, with the timer just make sure it’s not filling when you leave the boat. With the TW or Gobius there needs to be an on/off switch wired in for when you leave the boat.

My valve lives out side the boat and I use quick connects to be able to get off the dock quickly.

 

[Solly]

The thing about automatic anything is they automatically fail when you don't want then to.....
I'd vote for a hose from the city water to the tank fill with a ball valve. Think that would be a far better idea...

Sit in the cockpit, turn the handle, and listen for the overflow. Tough duty...

 

[Peter B]

The thing about automatic anything is they automatically fail when you don't want then to.....
I'd vote for a hose from the city water to the tank fill with a ball valve. Think that would be a far better idea...

Sit in the cockpit, turn the handle, and listen for the overflow. Tough duty...

I agree. This might even classify as a first world problem. Some things are best just kept simple. Just sayin'

 

[ksanders]

This seems simple. Keep your tanks full, or don’t.

you are in charge. You are on the boat. Leavbe a hose connected to the dock water to make it easy. check your tank level and fill it up.

I have a hard time thinking about a rteason to make it more difficult than it is.

 

[ksanders]

This seems simple. Keep your tanks full, or don’t.

you are in charge. You are on the boat. Leavbe a hose connected to the dock water to make it easy. check your tank level and fill it up.

I have a hard time thinking about a reason to make it more difficult than it is.

 

[Andiamo2018]

I don't want to leave the water fill open with just a hose sticking into it, just waiting for bird poop or spiders

I also don't want the tanks to even get as low as 3/4's when we are just sitting at the dock.

A water fill port with a hose cap would work with the timer.

As I said, we go out on the boat at least once a week and we live where it is reasonable to expect an earthquake large enough to cut off the water supply for a week or three

 

[BruceK]

I seem to recall reading danbohn was prone to earthquakes cutting off water supplies for weeks on end. Can`t be easy.
If your tanks fill, where do they overflow?
What time period would you set on your timer?

 

[Andiamo2018]

Lol Nothing like autofill when saying who you are.

My tanks overflow through the air vents and out the fill port. When the fill port is capped then just through the air vents. That's why I'll have to limit the volume and pressure so the air vent lines etc don't get blown off.

 

[BruceK]

My tanks overflow through the air vents and out the fill port. When the fill port is capped then just through the air vents....

My bow tank,one of 4 tanks,overflows into the bilge . No auto fill for us,but for you,perhaps. Even so,for safety, following the "What could possibly go wrong?" thought process,I`d do it manually.

 

[FF]

Raise the water tank vent above the top of the tank.

In a stanchion perhaps.

Then the dock water hose can simply be stuck in the fill and excess will run out onto the deck.

EZ to see EZ to hear , EZ to tend , no danger of turning the boat into a water tank.

 

[mahal]

I would definitely buy such device if available.

Also, if I were building or re-configuring my water tanks, they would be set up with built in float valves installed through an inspection/access port. It would be nice to fill the tanks without having to monitor it so I can do other pre-departure tasks.

I would use the float valves linked below. They're durable and very simple. Just adjust it to stop below the vent.

https://www.amazon.com/Stetson-Deve...pID=21eie7neGbL&preST=_SY300_QL70_&dpSrc=srch

 

[HopCar]

If you want to automate the process you need to install a float valve in the tank.
https://www.amazon.com/Adjustable-S...ocphy=9052029&hvtargid=pla-570500543272&psc=1

I see Mahal beat me to it.


I’d install a limiter on the dock hose so that you can’t sink the boat if an internal waterline breaks.
https://www.qcsupply.com/360006-flo...MIgNTO9Ynl3AIV3LfACh3bLw_6EAQYAiABEgJoMPD_BwE

 

[FF]

Why bother to use the tanks while in the slip?

A dockside water connection with a quality pressure control can simply be hooked after the FW pump .

Turn it on dockside when getting aboard and off when departing.

Cheap and seamless , with no wear to your FW pump.

 

[dhays]

Also, if I were building or re-configuring my water tanks, they would be set up with built in float valves installed through an inspection/access port. It would be nice to fill the tanks without having to monitor it so I can do other pre-departure tasks.

I have been know to create solutions where there really aren’t any problems. However, I really have a hard time understanding the OPs need/desire for such a device. I would go along with the keep it simple approach.

If I am around the boat, I can always here the water overflowing the vent and splashing into the water outside the boat. So I don’t have to monitor the process closely. OTOH, it would be nice to have a way to fill the water tanks more quickly. The fill pipe will only take the water so fast so it does take a while to fill all 375 gallons.

 

[MYTraveler]

FF has the best suggestion, if you really want to complicate your boat life.

A dockside water connection with a quality pressure control can simply be hooked after the FW pump .

Turn it on dockside when getting aboard and off when departing.

You may need a check valve in front of the pump.

 

[tiltrider1]

Just add a ball valve next to a window and you have a solution.

 

[janice142]

I have been know to create solutions where there really aren’t any problems.

This is so totally me... That is one issue I work on constantly. Complicating an already easy project, well, that's been known to happen all too many times. Argh.

I recall boats sinking at the dock because a hose fell off and water filled the bilges faster than pumps could remove same. This was when hooked to city water and DECADES ago.

I don't know that I would risk such a thing.

Even though I won't do it, I do have three bilge pumps (two 2k Johnson's and an 800gph SeaSense) which will keep my bilges empty even with full force water from a hose incoming.

And yes, I've checked that. The 800gph won't do it -- the first (lowest) 2000gph Johnson kicks in and keeps up with the water incoming.

Side note: Make sure your bilge pumps not only come on automatically but also pump water!!! My highest pump was checked monthly. When the bilges were flooded however for a test nothing happened with that one. Pump vibrated/no water pumped. The Johnson was old so I replaced it.

Always test bilge pumps

Anyway, I would not auto-fill anything. I would fill up prior to leaving though. Have your boat "ready to go at a moment's notice" and if that requires filling the tanks the evening before you depart, so be it.

Personally, I would not fill the tank on the last day. There are too many distractions and opportunities for failure at the last minute. Do it the day before

 

[tiltrider1]

Flow restricter and valve attached to timer switch. What isn’t shown are the quick releases.

Lot of old grandma’s on here who haven’t fully read the OP’s desires nor understand the solution. Flow rate is restricted, system only functions when some one is onboard.

 

[mahal]

I have been know to create solutions where there really aren’t any problems. However, I really have a hard time understanding the OPs need/desire for such a device. I would go along with the keep it simple approach.

It was easy for me. The OP wants to keep his tanks full all the time when at the dock for his own reasons that he has stated and is looking for a way to achieve this. For him, this isn't creating a solution without a problem.

I like the idea for a different reason. To me, adding water to my tanks is a PIA. I've even considered asking the boat washer to fill my tanks for an extra fee. This is not too different from swimming pool owners feeling that adding water to their pool weekly in the summer is a pain (I'm sure many here can relate), so builders now build pools with an auto-water-fill system. Why not boat water tanks too.

 

[koliver]

In the RV world, this has been done, so go look at some of the solutions there.
I can't inspect the plumbing in my motorhome, but with the "auto tank fill" switch on, I get both a full tank and street pressure inside the motorhome. With that switch "off" I still get street pressure. When disconnected from the street line, doesn't matter what position that switch is in, but the on board pump has to be on to get any pressure inside.

 

[FF]

"With that switch "off" I still get street pressure."

Depending on the town this can easily be 90 PSI or more, far above what many boat or RV are built to handle.

Some cruisers use a pressure regulator at the hose , others install a better regulator on board.
Due to local hard water these need to be repairable devices.

 

[koliver]

"With that switch "off" I still get street pressure."

Depending on the town this can easily be 90 PSI or more, far above what many boat or RV are built to handle.

Some cruisers use a pressure regulator at the hose , others install a better regulator on board.
Due to local hard water these need to be repairable devices.

I guess my post was incomplete.
Naturally, there are other factors to consider, such as street pressure, water hardness, chlorination, filtration, etc. Once addressed, the incoming water is under control.

 

[Boat]

Professor Henry Higgins asked "Why can't a woman be more like a man?"


It's just the nature of a boat, when filled with water, they sink. Auto-sink mode, no thanks.

 

[Bluevee]

Can I suggest -even though it sounds a bit strange a toilet float mechanism rigged into the top of the tank- just don’t use a used
one

 

[Boat]

Livestock water tanks have automatic fill systems.

But they're generally not on boats. Maybe the Ark had one. Until it sank.

 

[The Other Gary]

Livingaboard in the winter near Toronto we have heated water lines from the shore to the boat.
I use the shorewater inlet with a ball valve where it enters the boat.
My water pump is easily accessible and I have put a bypass before and after the pump with another ball valve. When the tanks are low I open the shorewater valve and open the bypass valve so city water fills the tank. Then I shut both off. No struggling with frozen hoses and no worries about sinking the boat. Sixteen years and three boats later I am still happy with the bypass and have witnessed two boats sink in winter that just didn't listen to advice.

 

[HopCar]

To avoid sinking the boat with a dockside water hook up you should install two things in the incoming hose, a pressure regulator to limit the pressure of the incoming water and a flow meter with shut off. You can set the flowmeter to a safe number of gallons and it will shut off the water before damage is done.

 

[Andiamo2018]

Thanks all for your comments! I for sure picked up a few ideas and feel better moving forward. For the curious this is what I've decided on:

Potable drinking water hose inside of old fire hose to keep water cool and protect from the sun.

An easy to access ball valve at the end of our finger pier to shut off the water when we leave.

A filter (probably just sediment filter outside).

A gallon / flow meter that can be set to shut off after 200 gallons.

Hopefully the filter and waterminder / shut off meter can be installed in a battery box (water lines in and out instead of battery cables) that can be painted to protect from UV.

At the boat a SHURflo pressure saver water entry.

Inside the boat and BEFORE the fresh water pump a 3 way valve with a limiter screw (probably just a wood screw stopping the handle from turning very far).

To fill the tank the valve can be turned a bit to back flow into the fresh water tanks. I can also remove the fill caps and turn the water on at a higher rate - hopefully helping to keep sediment from piling up on the bottom of the tanks. (My tanks have decent access ports and I already cleaned them out. There was years of stuff on the bottom including some big rust bubbles where the baffles were welded. All pinhole type leaks I've encountered in the past appeared to be a result of corrosion under gunk / sediment.)

Once the tanks are full I just turn the valve the other way for unlimited water in the boat.

When underway the valve is turned to open the lines from the tanks instead of from the city water. It will be easy to remember because there won't be any water coming out of fixtures until I do it.

The freshwater lines from the tanks and best place for the water entry happens to be under the galley sink so this all works out.

I'm already in the process of upgrading the bilge pumps.

I thought of a toilet ball valve bluevee but I had a hard time figuring out how to install it and I'm not sure they are completely potable as there is a lot of plastic involved. I can imagine a frame to hold the float valve and an inlet line to the top of the tanks where the city water could be attached. But there isn't room for that on any of my tanks and I don't want to mess with the cabinetry

HopCar, the waterminder type gallon meters look kind of cheap but they are specifically for potable water. We have a good carbon filter for drinking water but if I can cut down on how much plastic we drink I'm up for it.

As was mentioned, once the tanks are full I can just switch to city water and won't need the 'autofill' for the tanks. We use the boat more than once a month so hopefully sediment (in the fresh water and fuel tanks too) will get suspended and flushed out. Running the freshwater pump long enough to pump out the tanks entirely will take a long time. I think I can remember to do at least one tank a month (we have three) and that will be enough to keep everything fresh.

Whew! Now I just have to buy the rest of this stuff and install it!