Fresh Water Leak

[seabeau]

I have a fresh water leak somwhere on my 2001 460 sundancer. The pump runs intermittently even when water is not in use and drains the entire tank. I believe that I have checked all of the lines and am unable to find it. I had noticed moisture in the compartment underneath the salon floor. I had also noticed that my hot water does not work. Could this be related. Where is the hot water heater located. Any suggestions woudl be much appreciated.

 

[tobnpr]

You're missing 100 gallons of water, and there's no evidence of it anywhere?

 

[Boatdave]

I had my pressure relief valve on the hot water heater go bad. The overflow runs out the side of the boat so you would never see any water inside the boat. Mine wasn't leaking that bad to empty the water tank but you could hear the water pump cycle every so often.

 

[SearayTX]

Same thing just happened to my tank. Cabin bilge filled with water and pump was randomly turning on. Had a leak on one of the lines attached to water heater. Found it after I pulled apart my cabin. I will check there first next time.

 

[manfredr]

I have a fresh water leak somwhere on my 2001 460 sundancer. The pump runs intermittently even when water is not in use and drains the entire tank. I believe that I have checked all of the lines and am unable to find it. I had noticed moisture in the compartment underneath the salon floor. I had also noticed that my hot water does not work. Could this be related. Where is the hot water heater located. Any suggestions woudl be much appreciated.

Yes, I am also loosing water, found water coming out of the vent from the pressure relief valve, even with the water heater not turned on.
My research brought me to Atwood part# 91604. It looks like it fits all of Atwood's HWH
I went ahead and ordered one.
Has anyone used this part # as replacement?

Regards,

Manfred

2004 Sedan Bridge 420

 

[boatmailster]

Yes, I am also loosing water, found water coming out of the vent from the pressure relief valve, even with the water heater not turned on.
My research brought me to Atwood part# 91604. It looks like it fits all of Atwood's HWH
I went ahead and ordered one.
Has anyone used this part # as replacement?

Regards,

Manfred

2004 Sedan Bridge 420

there is a metal tag with part # right under lever

 

[Four Suns]

I'm dealing with the pressure relief valve leaking now (discovered it today). It's a slow drip out the end... every few seconds... Tried playing with it to re-seat it but that just made it leak more. I have an Atwood 20 gallon tank and it has a 1/2" T P valve on it that is rated for 75 psi. I can't find anyone that carries the Atwood part number that is in the manual... The Atwood 91604 part is for 150 psi. The current valve is a Watts part.. says "1XL 4 M 75 PSI" on it. From what I can tell, it has a Watts part number of 0004430 and the only place I can find it online is here:

http://www.sandersindustrial.com/item.cfm?id=7159

There are plenty of places, including Atwood, to get a 150 psi version... Don't really understand this as the new tanks all have 150 psi valves on them.

Went to Lowes and HD and there stuff was all 3/4".

I'm probably going to carry a spare one of these on the boat now... With that thing broken, you can't run the fresh water system on the boat. At a minimum, probably a good idea to carry an NPT brass plug for the opening on the water heater to plug the hole where this valve would go... Probably shouldn't run the water heater but at least the water system could be pressurized.

 

[Alex F]

Garry,

Can you check with local plumbing store for 1/2" part? Another idea, is it possible to get an adapter from 1/2" to 3/4" and fit the Home Depot version of relief valve?

 

[Four Suns]

There are two connections on the relief valve (tank side and discharge side that is plumbed to a hull side discharge) and the reducers/adapters/nipples would cost about the same as just getting a new valve. There's nothing special about these tank valves... Watts is the brand name at HD so they are not "inferior"... just not the right size. The local plumbing supply house here is not open on weekends... and my bet would be they would have to order it anyway.

Here's another thread on this issue:

http://clubsearay.com/forum/showthread.php?t=9226

 

[tbirdvet]

I have a fresh water leak somwhere on my 2001 460 sundancer. The pump runs intermittently even when water is not in use and drains the entire tank. I believe that I have checked all of the lines and am unable to find it. I had noticed moisture in the compartment underneath the salon floor. I had also noticed that my hot water does not work. Could this be related. Where is the hot water heater located. Any suggestions woudl be much appreciated.

When you say hot water does not work do you mean no pressure or just not hot? If no pressure that means your cold water is not getting to the hot water tank which may mean a leak at the line to the hot water tank which is why you are draining your system.

 

[Alex F]

There are two connections on the relief valve (tank side and discharge side that is plumbed to a hull side discharge) and the reducers/adapters/nipples would cost about the same as just getting a new valve. There's nothing special about these tank valves... Watts is the brand name at HD so they are not "inferior"... just not the right size. The local plumbing supply house here is not open on weekends... and my bet would be they would have to order it anyway.

Here's another thread on this issue:

http://clubsearay.com/forum/showthread.php?t=9226

I was just under the impression that you couldn't find the part, rather than you know where to get it but it just takes too much time. I guess for short term solution there're only two options:

1-take the relief valve off, dry it and try spaying it with a lubricant from all possible directions. Then, try try working it back and forth trying to get the lube get inside a far as possible and do the majic.

2-I think you metioned it before, take the valve off and install a plug until you get a new valve. If HD or Lowes don't have the right size plugs in bronze or brass, then use plastic plug from sprinklers section. You may laugh at my plastic plug suggestion, but it's only to be used for a short time frame. The only reason I suggest it is b/c that's what plumber used to plug my house sprikler system cleanout hole. Thephlon tape and plastic plug was used there for several years and it worked fine under the pressure of city water. So, I'm sure the same method will do the trick for a week or whatever it takes for you to get the new valve.

Just a thought.

 

[Four Suns]

Plastic plug works... heater won't be on anyway... Now that you mention it, I forgot I had one from a livewell pump I just bought that I removed... you just saved me $1.29.

The other thing I learned after reading stuff from Atwood (who the hell reads a water heater manual anyway?) is that the T&P valve can leak if the air bubble at the top of the tank goes away. The design of these heaters is such that the water connections are on the side of the tank and placed in such a way that there should be an air pocket on top. The cold enters the bottom and the hot exits the top and the T&P valve is the highest point on the tank side for water to exit. There is supposed to be an air pocket above the T&P valve which allows the water to expand when it heats up. It's basically a "built in" expansion tank.

What happens over time is the water absorbs the air pocket and when the water heats up, it has nowhere to expand so the T&P valve can drip... and I suspect if you have scale/hard water and it is left unchecked, the surface of the T&P valve can get deposits and constantly leak. Probably not good for the water heater either as I think it would stress it.

Atwood recommends you turn of the water pumps, open a sink faucet and open the T&P valve occasionally to keep this air pocket on the top of the tank... I tried that as a fix here but it didn't work... the valve is gunked up pretty bad... Looks to have been dripping awhile...

I admit... I didn't read the HW manual or know you had to drain the tank once in awhile via the T&P valve to keep this air pocket... But now we all know...

I'm wondering if it would be a good idea to flush the tank with Rydlyme once in awhile...

 

[Alex F]

Plastic plug works... heater won't be on anyway... Now that you mention it, I forgot I had one from a livewell pump I just bought that I removed... you just saved me $1.29....

I think the most important part is that you can go boating after 10min repair job. Today should be very nice day for boating :thumbsup:.

Thanks for sharing your findings on the WH air pocket.