fresh water leak

[rwa300]

I have an 03 Sundancer 300, and have a mysterious problem.

I turn on the fresh water pump, and hear it pressurizing the system, after which it shuts off. But it kicks on again every 30 seconds or so.

On my first cruise this season, I started with a full tank of fresh water, and 4 hours later it was empty.

So I obviously have a leak somewhere, but here is the strange part.

There is no water in the Bilge.

There are no leaks in the water system manifold

The bilge pump is not coming on

There is no water exiting any of the through-hull drains.

There is no water in the shower-drain pump area.

There is no water in the transom storage compartment.

I would appreciate any and all advice on how to troubleshoot this!


Bob

 

[tobnpr]

Where is the water heater located?

 

[rwa300]

The water heater is in the starboard aft section of the engine compartment. The water system manifold is on the port side of the engine compartment, so there are 2 hoses going back and forth.


Bob

 

[boatmailster]

check for leaky pressure valve on water heater and drain valve on heater also.
if no leaks found you have to look behind every faucet and shower valve, ice maker (if you have one) and t-connectors behind walls
is there fresh water wash-down in rope locker?

 

[Alegria]

Hmmm... Well I am guessing you about 40 gallons of water that went away over that 4 hours. The bilge pumps will turn on and pump off the water overboard and you might not notice while running, but if you were sitting still listening to the pump run every 30 secs and heard nothing then that is strange. If you checked the cabin sole storage areas and they are all dry and you are sure its not going into the bilge. Then I can only speculate could it be leaking into the transom locker then draining overboard down the swin platform????

 

[GMAN1]

Check your hose that goes from the water heater to your starboard engine. I work on alot of these boats in Ft Lauderdale and see this happen alot. The connection or hose always fails there and will leak down the front of your engine and you will not notice it until you start to get a rust stain. Also had a pin hole leak on the water heater outlet pipe. Pump would kick on and off every 30 seconds. Could not see the leak until I layed on engine and got a mist of relief. Good luck.

 

[rwa300]

Just returned from boat; turns out I had a leaky pressure valve.

I shut off the inlet to the hot water tank as a temporary fix.

Tried to unscrew the pressure valve, no luck (I was afraid to apply too much torque).


Are these things meant to be replaced or do people just replace the whole tank?


Bob

 

[tobnpr]

You can just replace the pressure relief valve. I think the temp may be a bit different than a household heater (others may clarify)- but you should be able to get one at a plumbing supply house.

So, where did all the water go??

 

[rwa300]

It was dribbling out the through-hole that is dedicated to the hot-water pressure relief; I didn't see it at first because the flow rate was low enough it did not form an easily visible stream


Bob

 

[boatmailster]

Just returned from boat; turns out I had a leaky pressure valve.

I shut off the inlet to the hot water tank as a temporary fix.

Tried to unscrew the pressure valve, no luck (I was afraid to apply too much torque).


Are these things meant to be replaced or do people just replace the whole tank?


Bob

there is a metal tag on valve, just replace valve with new one with same BTU rating
you may be able to find in your local home depot or rv place