Pressurized Water and hot water System

hinmo

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Never used either system too much, but am in a marina this year. Hot water works. Pressurized water (feeding the hot and cold system) hit a point today where it wouldnt stop pumping. Assume its out of water or has a decent leak somewhere (same thing essentially).

Any thoughts before I crawl into that darn mid cabin and tear down the wall for a better look?


btw - how does the pressurized water system know when to shut off?.....pressure?
 
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DennisG01

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If the fresh water tank is empty, it will just keep running and running since it can't build pressure. Fill the tank... does the problem go away? Seems like a simple thing to check.

Don't you have a city water hookup so you can use the water supply from the marina instead of the onboard tank?
 

MA208

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If it was winterized make sure it’s hooked back up. Might be an easy fix.
 

Legend

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Is the cold acting the same - if so it is most likely an empty tank. My hot water heater is in the bow in a Sailfish - not sure if the Marlin has same design.
 

Lsquared

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you do not need to have your fresh water pumps on while hooked into city water. the pressure system will just keeping pouring water in your boat without any pumps going if you had a leak after your check valve.

so if you have the pumps on and they are running you will most likely have an issue with the pump itself or at the accumulator tank if there are no holes in the lines. check the accumulator tank, the clear bowl sometimes cracks and will leak there.
 

DennisG01

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Good point about the hot water working. Hinmo... your post was a little contradictory - you said HW works... then you said the system doesn't work. Can you clarify?

FYI, having the fresh water fill cap off won't matter. Gotta let air in for water to come out. The fill cap is essentially the same as your vent.
 

georgemjr

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Fill tank to eliminate possibility of low water, then check screen on input side of pump to make sure it is not clogged (either one will cause a continuous pump situation because it is not getting enough water supply to build up enough pressure to shut down). if it is not either of those two does not solve it it will be a look and see to find the leak. I have found them at various locations at the hose connection (hose clamps) at various faucets.
 

hinmo

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Thanks for the input. I meant to say the heater does work. Its the pressurized water in general that keeps cycling. Its after a while tho, so it may just be an empty tank at this point....PIA to access and work on tho
 

hinmo

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Thx for the replies.

I guess (not too much confidence) that all is working. I filled the FW tank (did not seem empty), pressurized/heated the water and found 1 small leak at the check valve near the HW tank, ....seemed minor, but I guess I will run it as is and see what happens.


Wish there was a way to see the water level in the Fresh water tank.
 

DennisG01

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Just to be clear - maybe I'm not fully understanding what you're saying, yet...

-- You've mentioned "heating" the water numerous times. However, this has nothing to do with the pressurized water system or the pump. It's a completely different circuit. I just want to make sure that: Whether you are using the hot water or the cold water, the pump continuosly runs?

Did you fix the leak?

When I winterize a system, I open the pressure relief valve on the HWH to let it drain faster. If that's open, water would continuosly flow out the valve and overboard through the thru-hull. Just to be sure... check that. That would happen whether on dock water or onboard.

When the pump runs... is it constant?
 

hinmo

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Dennis - I apologize for not being succinct. Today, I filled the FW tank...it did not take as much as I expected, but certainly 5gal+ ?.

I am sure the pressurized pump feeds 1) the hot water tank, and 2) the cold water branch. agree?

I fixed the leak (loose clamp at the check valve), but it was only a slow-med dripper.

I heated water and ran both cold and hot for a several minutes. Satisfied that it is working ok (somewhat?) I shut her all down.

I used to have the GW diagram of the water system that showed the connections, I need to find that.

Wow -at 62, and 6'3", 265....that mid berth access to the water pump and heater SUX

BTW - 1999 Marlin
 

DennisG01

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Did the pump now stay off after you closed your faucets?

"I am sure the pressurized pump feeds 1) the hot water tank, and 2) the cold water branch. agree?
-- Yes. It works the same way your home does or the way your boat does when hooked into dock water. The dock water simply ties into the system downstream of the pump, but before anything else.

FYI... you don't have to heat the water to get water out of the hot water side of the faucets. It'll just come out cold.

Sounds like you need to hire a bilge monkey! In other words, a 12-year old kid. They work cheap AND you'll even be teaching them sumthin'!
 

hinmo

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The dock water simply ties into the system downstream of the pump, but before anything else.

This statement I dont understand. Do I have another input for water other than the water tank? I dont know about it if I do....pls explain
 

DennisG01

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Does your boat NOT have a hose connection for dockside water? Meaning... a female garden hose connector where you would attach a garden hose from the dockside water spigot?

Did the pump now stay off after you closed your faucets?
 

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DennisG01

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I put this link up further but you may have missed it. this pretty much applies to all boat water systems that have dock side intake.
https://www.westmarine.com/WestAdvisor/Pressurized-Freshwater-Systems
That's a pretty good visual to get an idea of a system. Some things that not all boats may have though are the check valve, mixer valve and expansion tank. But overall, that decent diagram. Checking yoru owner's manal should (hopefully, if it's decent) give a better diagram for a specific boat/ model.
 

georgemjr

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#1) I have never owned a Grady that had a water hookup and I have owned a 24, 28, 33, 30, and now a 33 again ranging from 1988 to 2007. If they have that, my guess is it is on a newer boat than 2007.

2) If the water pump comes on intermittently, it is a leak and in this case, it sounds like you found it.
 

DennisG01

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#1) I have never owned a Grady that had a water hookup and I have owned a 24, 28, 33, 30, and now a 33 again ranging from 1988 to 2007. If they have that, my guess is it is on a newer boat than 2007.
Wow, I find that odd. I believe you - just find it odd. I've NEVER owned a boat with a hot/cold water system that DIDN'T have a dockside hookup. I've had boats with a cold water only system that didn't have the hookup - but never one with a full system.