using shore water supply at same time the boats fresh water pump is running

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Too chez

Member
Joined
Oct 5, 2013
Messages
11
Location
Emit
Vessel Name
Pearl
Vessel Make
Mckinna 57
I have a fresh water supply system that consists of a Groco Senior water pump with check valve to a large Head Hunter accumulator tank. The tank tees directly to a 1 inch supply hose for the Head Hunter heads that require that volume of water between 40 and 60 PSI to flush appropriately. In addition the 1 inch hose tees off to ¾ inch hose just forward of the accumulator tank for the rest of the boats fresh water outlets including a washing machine. These outlets( not the heads) receive their water after it first passes through a ship wide seagull 6 gal/min filter system. The head supply line is not part of the filtered system. Thus if I connect t to a shore water supply outlet that bypasses pump and accumulator tank the toilets cannot flush. However while the heads are isolated the rest of the boat’s fixtures are connected to the shore system and it works great. The shore supplied pluming also by passes the filter and I don’t waste filter life on already purified water.

My problem is if I am connected to the shore water system the heads do not work, however I do want to isolate the washing machine and showers from the filter system when in port and not waste filter life I also don’t want to run new pluming to the whole boat. I do not have a multi outlet manifold that would let me isolate outlets. So if I can run the boats fresh water supply pump to get the unfiltered water through the bypaased 1inch hose at 40 to 60 psi I need for the heads at the same time I am connected to the shore water supply for the rest of the boats outlets which includes the water consuming washer and showers. Problem solved. can I or can’t If I can is there anything I need to add to ensure nothing is damaged or back fed to the pump or filter.
 
Maybe you could filter water going into boat tanks and not use "full time" dock water. Safer too- avoids flooding the boat if a line breaks while on dock water pressure.
 
thank you but that is not the problem nor does it solve the issue I am not worried about filtering water. I want to use both the shore side supply for the outlets and the boats tanks and fresh water pump to supply the bypassed filter head line to make the heads flush properly Can I use both at the same time?
 
I'd have to see a diagram of your plumbing but the answer is likely yes you can run the whole boat off shore water including the head system. It's kind of strange that it is not set up that way already.
 
thank you but that is not the problem nor does it solve the issue I am not worried about filtering water. I want to use both the shore side supply for the outlets and the boats tanks and fresh water pump to supply the bypassed filter head line to make the heads flush properly Can I use both at the same time?

If you are not connected to dock water do the heads, washer and other interior outlets work OK from boat water tanks?
 
I’m confused. If you tee the dock water into the system anywhere down stream from the pump it should pressurize the whole system. Do you have some extra check valves that prevent this?

Do I understand that the dockwater tees into the system downstream of the filter? If so there must be a check valve between the tee and the filter to prevent back flow through the filter.

Are you saying that the dock water doesn’t supply enough water to flush those Head Hunter toilets? I’m actually surprised you flush them with fresh water. If you’ve got the Head Hunter Jet Toilets they use a lot of water with each flush.

My guess is that with properly positioned check valves you could run both systems at the same time.

Be sure to install a volume limiter in the dock water supply. It’s pretty easy to sink a boat hooked to dock water.
 
Thank you. Let me try to clear up the plumbing layout. the pressure and volume for the heads require a short burst of water through a 1” line at between 40 and 60 psi so they are purposely supplied water right after the accumulater tank and direct to the heads solenoid valve. No possible contact thru the filter. Your right they require a lot of water but we carry a lot of water. The fresh water from the same accumulater tank also goes to a smaller diameter barb on the tee that sends water thru a 3/4 inch hose to the filter, out thru a check valve and on its way to all the other outlets. The shore supplied water pressure, regulated at the boats inlet, goes directly to the plumbing AFTER the filter OUT check valve.

So from what you said I can run both systems at the same time when I am docked and not force any water thru the filter. Right?
 
Yes they work fine the heads get water from the same accumulated tank except thru a larger diameter hose that does not run through the filter. The rest of the system runs thru the other arm of the tee to the filter a check valve and on to all the ships outlets. I am trying to save filter life when docked and not have to go in the engine rum to close a gate valve after the filter.
 
With the check valve between the dock water tee and the filter, I think you’re ok running both systems. I’ve never seen it done like that but I don’t see why it wouldn’t work.

Maybe put a check valve in the dock water line to prevent pumping your tanks into the city system. I think that is pretty unlikely.

I would put a volume limiter on the incoming city water. If something fails in the boat system the dock water can fill the boat pretty quick.
 
With the check valve between the dock water tee and the filter, I think you’re ok running both systems. I’ve never seen it done like that but I don’t see why it wouldn’t work.

Maybe put a check valve in the dock water line to prevent pumping your tanks into the city system. I think that is pretty unlikely.

I would put a volume limiter on the incoming city water. If something fails in the boat system the dock water can fill the boat pretty quick.

And unplug shore power so the boat doesn't burn down. Better yet have the boat pulled out of the water so there is no chance for sinking.

Or maintain your plumbing and have adequate bilge pumps... oh, that's TOO hard..
 
It will only work the way you want IF the shore supply has higher pressure than what comes out of the accumulator tank.
To make sure it works together, you need to have a valve on the accumulator side of the hose the shore supply ties into. The check valve won't do it unless the shore supply is the greater of the pressures ALL the time.
 
And unplug shore power so the boat doesn't burn down. Better yet have the boat pulled out of the water so there is no chance for sinking.

Or maintain your plumbing and have adequate bilge pumps... oh, that's TOO hard..


Many boaters on both sides of the full time connection to shore water approach. For those who are always connected the use of a water timer makes sense, and is cheap.

I had two leaks in my fresh water system over twenty years. One was underway in heavy weather in which case I dumped 300 gallons of fresh water into the bilge. The second occurred at the dock when I was off the boat but connected to shore water. A neighbor spotted two bilge pumps going and turned off the water supply.

After that I used a water time except in St. Lucia where the water pressure was very high and blew out hose connections repeatedly and at 30 cents a gallon I avoided shore water except to fill the tanks.
 
Interestingly, our Marina discourages water lines affixed to vessels 24/7. They mention ruptured hoses, freezing weather water losses, insurance and liability as rationale.
 
Interestingly, our Marina discourages water lines affixed to vessels 24/7. They mention ruptured hoses, freezing weather water losses, insurance and liability as rationale.

During freezing weather of course not. Regardless a pressure regulater is needed and you can get them at whatever rating you require. Solves the "St. Lucia" issue mentioned.
 
TC
Three questions:

- Would a pressure regulator on the water hose dialed down to balance against your onboard pressure tank help? Especially with the aforementioned check valve re-location.
- Why do you need an onboard water filter? Maybe the filter placed on the water hose would work, seen many do this.
- Can you gravity drain your water tanks to the bilge? The tanks are great grit traps and in my case obviate the need for an onboard filter. Not to mention good dock water throughout WA, BC and AK.

We don't like to let our tanks sit unused, water gets stale. That is one of many reasons we don't favor a "permanently" plugged in water hose. With 400 gallons of onboard storage a ten day to two week re- fill is all we need. Plus I wash the boat at least once per week (not in cooler months) so the hose is there and available.
 
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I have shore / city water AND the fresh water pump is still powered on. It works fine. But I have a gallon meter on my shore water that really limits the flow / volume of water coming into the boat. With the fresh water pump showers are noticeably better :)

We also have a filter on the incoming hose as mentioned. Then we have a separate and better filter for drinking water and the instant hot water at our galley sink.

Here is a link to what it looks like if you are interested.

https://youtu.be/4yMtk_Dk1cU


https://youtu.be/4yMtk_Dk1cU
 
I am not sure if this helps, but, we leave our water pump on when we are connected to city water. If the city water pressure is higher than the pump regulator setting, the pump does not come on. If the city water pressure is less than the pump regulator setting, then the pump comes on to supplement the city water. Our pump is a Par-max variable speed pump. We rarely notice that the pump has been supplementing the city water for a week or so, when we notice the change in trim lets us know the water tanks are nearly empty. Been doing it this way for 10 years now.
 
Sounds like your filter is downstream from the tanks, (which it should be since there are unusual accumulations in the tanks that could also use some filtration). But why worry about reducing the life of the filter with clean "city water"? How does clean water clog a filter? Unless it's the cost that is bothersome; In my opinion, Seagull replacement filters are grossly overpriced.



You could replace that with two 9 inch cartridges and housings, in tandem, at considerably less cost. The first would be a 10 or 20 micron pleated cartridge for sediments followed by a 1 micron for critters you don't want in your system. Change them every 6 months. Buy them from a plumbing or industrial wholesaler; not a retail outlet. Easy, and no need for any special bypass to extend cartridge life.
 
We just fill the tanks with a hose. No water connections at all. Refill the tanks once a week. KISS.
 
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